CCNP Route: 300-101
PPP: Point to Point Protocol
it is open standard protocol
it is layer 2 protocol
it can encapsulate any routed protocol. (IPv4,ipv6, IPX, APPLE Talk)
it support authentication but other layer 2 protocol doesn't support
it can aggregate multiple serial link between two router
it also support header compression
it can use different subnet ip on single segment.
it support one way authentication and two way authentication
in ppp we can define static-default route dynamically
how to configure ppp
r1(config-if)#encapsulation ppp
r#debug ppp negotiation
r2(config-if)#encapsulation ppp
r2#debug ppp negotiation
r#show ip route
Phases in PPP
1 Down:
in this phase, ppp is down, this message is seen after the link and ppp are completely down.
2 Establishment phase:
it performed by LCP protocol
it will establish link connectivity and will perform authentication
when device receive an indication that the physical layer is up and ready to be used.
3 Authentication phase:
PPP Authentication phase is option.
it occurs when PPP authentication is configured on link, then it will come in authentication phase
4 Network control Phase/UP :
it performed by NCP protocol
it will exchange ip address of interfaces between two router (IPCP Protocol)
r1(config)#interface loopback 1
r1(config-if)# ip address 1.1.1.1 255.255.255.255
r1(config)#int serial 0/0
r1(config-if)#ip unnumbered loopback 1
r2(config)#interface loopback 1
r2(config-if)# ip address 2.2.2.2 255.255.255.255
r2(config)#int serial 0/0
r2(config-if)#ip unnumbered loopback 1
r#show ip route
r1(config)#int serial 0/0
r1(config-if)#no peer neighbor-route (router will not receive route from other router)
r1#show ip route
Note: CDPCP is reponsible to take cdp based packet from one router to another. if CDPCP is disabled thn we cant see neighbor info in cdp cmd.
R#clear ppp all (this command can clear process of ppp but it is avaible in ios 15.0 only)
how to configure default-route toward ISP automatically
cust(config)#int serial 0/0
cust(config-if)#ppp ipcp route default
cust#show ip route (sometime route will not come in routing table for that clear ip route *)
how to configure one-way authentication (PAP)
in this isp will authenticate to customer router
isp(config)#username cisco password cisco
isp(config)#int serial 0/0
isp(config-if)#ppp authentcation pap
cust(config)#int serial 0/0
cust(config-if)#ppp pap sent-username cisco password cisco
how to configure two-way authentication (PAP)
isp(config)#username cisco password cisco
isp(config)#int serial 0/0
isp(config-if)#ppp authentcation pap
cust(config)#int serial 0/0
cust(config-if)#ppp pap sent-username cisco password cisco
cust(config)#username cisco password cisco
cust(config)#int serial 0/0
cust(config-if)#ppp authentcation pap
isp(config)#int serial 0/0
isp(config-if)#ppp pap sent-username cisco password cisco
how to configure ppp authentication with AAA server.
isp(config)#AAA new-model
isp(config)# AAA authentication ppp ccie group radius group tacacs+ local
isp(config)#username cisco passsword cisco
isp(config)#interface serial 0/0
isp(config-if)#ppp athentication pap ccie
cust(config)#int serial 0/0
cust(config-if)#ppp pap sent-username cisco password cisco
how to connect isp router with radius or tacacs
isp(config)#radius-server host 10.10.10.10 key cisco123
isp(config)#tacacs-server host 20.20.20.20
isp(config)#tacacs-server key cisco123
how to configure chap authentication (two-way)
isp(config)#username cisco passsword cisco
isp(config-if)#encapsulation ppp
isp(config-if)#ppp authentication chap
cust(config-if)#ppp chap hostname cisco
cust(config-if)#ppp chap password cisco
cust(config)#username test password cisco
cust(config-if)#encapsulation ppp
cust(config-if)#ppp authentication chap
isp(config)#int serial 0/0
isp(config-if)#ppp chap hostname test
isp(config-if)ppp chap password cisco
how to aggregate multiple serial link in ppp
isp(config)#interface serial 0/0
isp(config-if)#encapsulation ppp
isp(config)#interface serial 0/1
isp(config-if)#encapsulation ppp
isp(config)#interface multilink 1
isp(config)#int serial 0/0
isp(config-if)#ppp multilink group 1
isp(config)# int serial 0/1
isp(config-if)#ppp multilink group 1
how to configure authentication in multilink interface
isp(config)#int multilink 1
isp(config-if)#ppp authentication chap
isp(config)#username cisco password cisco
cust(config)#interface multilink 1
cust(config-if)#ppp chap hostname cisco
cust(config-if)#ppp chap password cisco
how to give default route on multilink interface
cust(config)#interface multilink 1
cust(config-if)#ppp ipcp route default
cust#show ip route
PPPoE
It stand for PPP over ethernet
it wil add ppp information (8byte) between ethernet header and ip header
it will not remove ethernet header
PPPoE server configuration
r1(config)#interface virtual-temple 1
r1(config-if)#encapsulation ppp (default is ppp)
r1(config-if)#ip address 12.1.1.1 255.255.255.0 (we can call loopback address)
r1(config)#bba-group pppoe test
r1(config-bba-group)#virtual-templete 1
r1(config)#interface ethernet 0/0
r1(config-if)#pppoe enable group test
PPPoE client Configuration
r2(config)#interface dialer 10
r2(config-if)#encapsulation ppp
r2(config-if)#ip address 12.1.1.2 255.255.255.0 (we can call loopback address)
r2(config-if)#dialer pool 100
r2(config)#interface ethernet 0/0
r2(config-if)#pppoe-client dial-pool-number 100
how to configure authentication in PPPoE
r1(config)#interface virtual-templete 1
r1(config-if)#ppp authentication chap
r1(config)#username cisco password cisco
r2(config)#interface dialer 10
r2(config-if)#ppp chap hostname cisco
r2(config-if)#ppp chap password cisco
how to configure dynamic ip addrss to pppoe client from dhcp server
r1(config)#ip dhcp pool ccie
r1(dhcp-config)#network 12.1.1.0 /24
r1(dhcp-config)#default-router 12.1.1.1
r1(config)#ip dhcp excluded-address 12.1.1.1
r1(config)# interface virtual-template 1
r1(config-if)#peer default ip address dhcp-pool ccie
r2(config)#interface dialer 10
r2(config-if)#encapsulation ppp
r2(config-if)#ip address negotiated / ip address dhcp
if client is not receiving ip from dhcp server than clear ppp all or flap interface
how to provide dynamic ip address to client from local pool
r1(config)# ip local pool ccie1 12.1.1.10 12.1.1.10
r1(config-if)# peer default ip address pool ccie1
PPP Negotiation packets:
1 Configure-Request:
device will send confreq msg to open a connection to the peer.
it contain configuration option and values the sender wishes the peer to support.
if the peer responds with a confrej or confnak msg then the router sends another confreq msg.
2 Configure-Reject:
if configuration option received in the confreq msg is not acceptable thn device will send confreject
3 Configure-Nak:
if received configration option is acceptable but some value is not acceptable thn router transmit a confnak msg
Configure-Ack:
if all options and values in confreq msg are acceptable thn router will transmit confack msg
Terminate-Request:
this msg is used to initiate and LCP close
Terminate-Ack:
this msg is tranmitted in reponse to the rerminate-req msg
Types of Layer3 switching
Process switching
Fast-switching
CEF (cisco express forwording)
Process switching
Fast switching
Route Processor
Switch engine
CEF (cisco express forwording)
There is two types of table in cef
FIB: it is replica of RIB, It is present inside data plane only.
Adjecancy
There is two types of CEF
Centeralized CEF
Decenteralized CEF
Type of adjacency table
Null adjacency: null adj table will be responsible to handle all those packet which are forworded towards nulls interface
Drop adjacency: this table is basically responsible to handle all those packet which are encounteredwith mismatch of encapsulation or crc error.
Discard adjacency: this table is resonsible to handle all those packet which are discarded by an acl
Glean adjacency: this table is responsible to have information about all directly connected network and whenever a packet will mode to a any directly connected network thn all those packet will be handled by glean adjacency.
Punt adjacency: this table is reponsible to handle those packet which is not processed by cef and forworded to control plane to process these packet
r1#show ip cef 3.3.3.3
r#debug ip packet (enable on all routers)
r2(config)#no ip cef
r2(config-if)#no ip route-cache
IP addressing version 4, Subnetting and VLSM
ARP Process
IP Routing
routing is a process or technique to identify the path from one network to another network
a router must know the following information to route the packets from one network to another network.
destination network
neighbor router from which it can learn about remote network
possible number of router to reach the destination
best route to reach the destination
There are two types of Routing
Static routing
Dynaming routing
Static Routing
Static routing is specified by an administrator in which an administrator manually specifies all routes
Advantage:
security
low CPU utalization
Efficient in small network
usually used in small network
Disadvantage:
Time consuming
Not good for large network
burden on an administrator
There are three way to configure static route
By using next-hop address
by using exit interface
by using next-hop and exit interface
it will install both route into routing table. bcz it will check logest prefix match and prefix match is same. after that it will check a.d. value and a.d. is also same.after that it will metric and static route matric is always 0 so both route metric is also same.. so it will install both routes into routing table. but it will not perform load-balancing
it will preffer that path which is installed first into routing table
Floating Static Routing
floating static routing than one route will be save in routing table and second route will be same in nvram if first route goes down than second route will automatically placed into routing table.
r(config)#ip route 0.0.0.0 0.0.0.0 12.1.1.1
r(config)#ip route 0.0.0.0 0.0.0.0 23.1.1.1 2
EIGRP
it stand for Enhanced interior gateway routing protocol
it is open standard protocol.
it is an IGP Protocol
it is a hybrid/advance distance routing protocol.
metric is bandwidth+load+delay+reliability+mtu
hello timer 5sec and hold timer 15sec.
hop count bydefault 100 and maximum 255.
first time full update after that triggered update
it is a PDM Protocol (protocol dependant module).
administrative distance is 90/170/5
it is a classless routing protocol
it support vlsm
it support discontigious network.
bydefault auto-summary is enabled/ disable in ios version 15.0 and above.
multicast address 224.0.0.10
protocol number 88.
there are two version of eigrp v2 and v3
we can run maximum 30process on a single router
it support equal load-balancing, bydefault 4, max 16/32.
it uses dual algorithem for best path selection (diffusing update algorithem)
it will create neighbor with using primary address.
DUAL (Diffusing update algorithem)
it is an algorithem used by eigrp for select lowest cost loop free path for each possible destination
it also provide fast convergence.
if in topology table multiple path available than it will run dual and it will select best route and put it in routing table
there are four terms of dual: 1 FD, 2 RD, 3 Successor, 4 Feasible Successor
FD: Feasible Distance
total metric from source to destination or you can say that a caculated metric of successor is called FD.
RD: Reported Distance
A router's FD will be called RD to its neighbor
Successor:
A successor route is the best route to reach destination network
a successor route is lowest cost to reach destination
a successor route will stored in topology table as well as in routing table.
Feasible Successor
it is a backup path of successor which stored in topology table.
eigrp will keep up to 32 feasible successor in topology table in ios version 15.0
feasibility condition
AD>RD of current successor
Types of EIGRP packets
Hello
Update-RTP
Query-RTP
Reply-RTP
ACK
RTP: Reliable Tranport Protocol
it is used for detecting packet loss and to ensure ordered delivery of the packets
Hello
hello packet is used for neighbor discovery and for keepalive.
contents of hello
version
opcode: hello,ack =5, update=1 , query =3, reply=4
checksum
autonomous system number
eigrp parameters: k values, hold time
sequence and acknowledge: used for acknowledged packet only (update,query, reply)
software version: information about the ios version
requirment for neighborship
A.S. must match.
K values must match.
Authentication must match.
Network id must match.
update:
update msg can be unicast or multicast
it used rtp protcol
contain (subnets/prefix length, delay, bandwidth, mtu, load, reliability, hop count.)
update packets are sent between neighbor to build the topology table and routing table.
if there is static neighborship between router than update will be unicast.
Ack:
ack msg always sent as unicast.
ack is not used in the case of hello.
it is just for rtp packets
Query:
query packets are sent by a router when successor route fail and ther is no feasible successors in the topology table.
the routers places the route in active state and sent a query to its neighbors for an alternetive route.
query msg are sent as a multicast 224.0.0.10
Reply:
reply packets are sent in response to query packets, the responding router has an alternetive route.
reply packets are sent as a unicast to the querying router.
stuck in active
when a router noticess that a route failure and there is no feasible successor that route move in active state from passive,
that router sends a query msg to its neighbor and it will wait for 3min for reply.
if router does not receive a reply within active timer, that route will considered stuck-in-active state
if router not receiving reply within 3min router will flap the neighborship with its neighbor
router(config-router)#timers active-time (value)
solution of stuck in active
Disable active timers
Stub router
router(config-router)#eigrp stub
Summarization
types of table in eigrp
Neighbor table
Topology table
Routing Table
Neighbor Table
it contains information about its neighbor
r#show ip eighrp neighbor
Topology Table
it contains all destination advertise routes by neighbor routers which come from the nbr routing table
r#show ip eigrp topology
r#show ip eigrp topology all-links
Routing Table
it contain the best route to each remote network and this path called successor
it will contain three types of route: internal, external, summary
r#show ip route
r#show ip route 1.1.1.0
r#show ip route eigrp
r#show ip route eigrp 100
Null 0:
it is a loop avoidance mechnism entry stored in routing table,
null0 will be created only in case of summarization (auto & manual)
if any traffic goes towards null0 thn it will drop by eigrp
Metric Value: it use composite metric for route selection
k1*1 = Bandwidth (measured in kilobytes per second)
k2*0= Load (numbers from 1 to 255)
k3*1= Delay (measured in 10's of microsecond)
k4*0=reliability (numbers from 1 to 255, 255 is most reliable)
k5*0= MTU
serial: bandwidth 1544kbps, delay 20,000 microseconds
fastethernet: bandwidth 100000kbps, delay 1000 microsecond
loopback: delay 5000 microsecond.
how to change metric weights
R(config-router)#metric weights 0 1 1 1 1 0
Passive Interface
router(config-router)#passive-interface default
router(config-router)#passive-interface ethernet 0/0
Unequal-cost Load-Balancing
eigrp automatically supports load balancing over four equal-cost routes.
eigrp support up to 32 equal-cost path with ios version 15.0, in previous ios 16path
Varriance: it will multiply with successor when dual algorithem run on topology table
(default1, 1to128).
router(config-router)#varriance (1 to 128)
Offset-list
it is used for equal cost load-balancing or path manupulation
router(config)#access-list 1 permit 1.1.1.0 0.0.0.255
router(config-router)#offset-list 1 in 100 (on all interface)
router(config-router)#offset-list 1 in 100 ethernet 0/0 (for spacific interface)
router#show ip protocol (to check offset list).
how to change maxium path
bydefault eigrp support equal cost load balancing in 4paths
we can change it up to 32 in ios version 15.0 and above
router(config-router)#maximum-path 8 (1 to 32)
MD-5 Authentication
r1(config)#key chain cisco (key chain name can be different)
r1(config-keychain)#key 1
r1(config-keychanin-key)#key-string cisco1
r1(config-if)#ip authentication mode eigrp 100 md5
r1(config-if)#ip authentication key-chain eigrp 100 cisco
r1#show key chain
MD-5 Authentication with multiple key
r(config)#key chain cisco
r(config-keychain)#key 1
r(config-keychain-key)#key-string cisco1
r(config-keychain-key)#send-lifetime 10:00:00 16 dec 2015 10:00:00 17 dec 2015
r(config-keychain-key)#accept-lifetime 10:00:00 16 dec 2015 10:00:00 17 dec 2015
key 2
send-lifetime 09:59:00 17 dec 2015 10:00:00 18 dec 2015
interface link working in which A.S
r#show ip eigrp interface
how to check hello timer on any interface
r#show ip eigrp interface detail
how to change hello timer and holddown timer
router(config-if )# ip hello-interval eigrp 100 10
router(config-if )#ip hold-timer eighrp 100 30
advertise route with redistribution command
it will show as a external route in routing table
router(config-router)#redistribute connected
how to change max hop count
r(config-if)#metric maximum-hopes 1
split-horizon
it is a loop avoidance technique, bydefault it is enable on interface
r(config-if)# No ip split-horizon eigrp 100
r(config-router)# eigrp stub
Route Filtering
route filtering is used to filter the unused routes of a router. it is used to reduce the size of routing table. we can perform route filtering by using 4 methods.
Standard ACL
Extended ACL
Route-map
Prefix-list
Route Filtering by using standard Acl
r(config)#access-list 1 deny 3.3.3.0 0.0.0.255
r(config)#access-list 2 permit any
r(config-router)#distribut-list 1 in fa 0/0
r(config-router)#distribut-list 1 in
r#show ip protocol
route filtering by using extended Acl
source: next hop address from which router receiving the routes
destination: the routes which we want to filter
r(config)#access-list 101 deny ip host 12.1.1.2 3.3.3.0 0.0.0.255
r(config)#access-list 101 permit ip any any
r(config-router)#distribut-list 101 in
r#show ip protocol
r#show access-list 101
Route filtering by using Route-Map
r(config)#access-list 1 permit 3.3.3.0 0.0.0.255
r(config)#route-map cisco deny 10
r(config-route-map)#match ip address 1
r(config)#route-map cisco permit 20
r(config-router)#distribute-list route-map cisco in
r#show route-map
Route filtering by metric
r(config)#route-map cisco deny 10
r(config-route-map)#match metric 1000
r(config)#route-map cisco permit 11
r(config-router)#distribut-list route-map cisco in
filter route with using metric between 100 to 200
200-100 =100
100/2=50
100+50=150 (150 +- 50)
router(config)#route-map cisco deny 10
router(config-route-map)#match metric 150+-50
router(config)#route-map cisco permit 11
router(config-router)#distribute-list route-map cisco
Route filtering by using prefix-list
any= 0.0.0.0 /0
ge= greater thn
le= less thn
r(config)#ip prefix-list 1 deny 1.1.0.0/16 ge 24 le 24
r(config)#ip prefix-list 1 permit 0.0.0.0/0 le 32
r(config-router)#distribute-list prefix 1 in
r#show ip prefix-list 1
Route filtering by using A.D. 255
r(config)#access-list 1 permit 1.1.1.0 0.0.0.255
r(config-router)#distance 255 12.1.1.2 0.0.0.0 1 (for specific route from 12.1.1.2)
or
r(config-router)#distance 255 12.1.1.2 0.0.0.0 (for all route from 12.1.1.2)
how to filter internal/external route
r(config-router)#distance eigrp 90 255.
r(config-router)#distance eigrp 255 170.
Load-balancing with using summarization
r5(config-if)#ip summary-address eigrp 100 5.5.0.0 255.255.252.0 (interface fa 1/0)
r5(config-if)#ip summary-address eigrp 100 5.5.4.0 255.255.252.0 (interface fa 1/1)
how to configure summarization with leak-map
r5(config)#access-list 10 permit 5.5.3.1 0.0.0.255
r5(config)#route-map cisco permit 5
r5(config-route-map)# match ip address 10
r5(config-if)#ip summary-address eigrp 100 5.5.0.0 255.255.0.0 leak-map cisco
how to change A.D. value for summary route/ for null
r5(config-if)#ip summary-address eigrp 100 5.5.0.0 255.255.0.0 91
how to restrict router to install summary route toward null0
r5(config-if)#ip summary-address eigrp 100 10.1.0.0 255.255.252.0 255
static neighborship
r3(config-if)#no ip split-horizon eigrp 100
r3(confif-if)#no ip next-hop-self eigrp 100
Propogate/Generate default route in EIGRP
Redistribut static
summarization
ip default-network
network 0.0.0.0
redistribute static
router(config)# ip route 0.0.0.0 0.0.0.0 null 0
router(config-router)# redistribute static
summarization
router(config-if)# ip summary-address eigrp 100 0.0.0.0 0.0.0.0
IP default-network
r(config)#interface loopback 1
r(config-if)#ip address 192.168.101.1 255.255.255.0
r(config)#router eigrp 100
r(config-router)#network 192.168.101.0
r(config)# ip default-network 192.168.101.0
network 0.0.0.0
router(config)# ip route 0.0.0.0 0.0.0.0 null 0
router(config-config)#network 0.0.0.0
Redistribute rip/ospf into EIGRP
router(config-router)#redistribute rip metric 1544 0 255 1 1500
router(config-router)#redistribute ospf metric 1544 0 255 1 1500
or
router(config-router)#redistribute rip
router(config-router)#redistribute ospf 100
router(config-router)#default-metric 1544 0 255 1 1500
advance redistribution in eigrp
router(config)# route-map tag1 permit 10
router(config-route-map)#set tag 600
router(config-router)# distribute rip metric 1544 0 255 1 1500 route-map tag1
router(config)#route-map tag2 permit 10
router(config-route-map)#set tag 700
router(config-router)# distribute ospf 100 metric 1544 0 255 1 1500 route-map tag2
router(config)#route-map tag3 permit 10
router(config-route-map)#set tag 800
router(config-router)#redistribute eigrp 200 route-map tag3
router#show ip route 5.5.5.0
router#show ip eigrp topology 5.5.5.0 255.255.255.0
router#show ip eigrp topology
Route filtering with tag value
router(config)#route-map filter deny 10
router(config-route-map)#match tag 700
router(config)#route-map filter permit 11
router(config-router)#distribute-list route-map filter in
filter external/internal route with using route-map
router(config)#route-map filter1 deny 10
router(config-route-map)#match route-type external/internal
router(config)#route-map filter1 permit 11
router(config-router)#distribute-list route-map filter1 in
filter route from specific protocol
router(config)#route-map ext deny 10
router(config-route-map)#match source-protocol rip/eigrp200/ospf 100/static/connected
router(config)#route-map ext permit 11
router(config-router)#distribute-list route-map ext in
Router-id in eigrp
external route will carry router-id of originating router.
router#show ip eigrp topology 5.5.5.0 255.255.255.0
how to electe Router-ID in eigrp
router(config-router)# eigrp router-id 10.10.10.10
1 Highest IP address of loopback interface
2 Highest IP address of physical interface
EIGRP Stub Routing
r(config-router)# eigrp stub (it will forword connected and summary route only)
r(config-router)#eigrp stub receive only (it will not forword any route)
r(config-router)#eigrp stub connected (it will forword only connected route)
r(config-router)# eigrp stub summary (it will forword only summary route)
r(config-router)# eigrp stub redistributed (it will forword only redistributed route
Policy based routing
Policy based routing can be used to change the next hop ip address. this can be usefull to over rule your routing table for certain traffic types.
router(config)#access-list 101 permit ip any 3.3.3.0 0.0.0.255
router(config)#route-map cisco permit 10
router(config-route-map)#match ip address 101
router(config-route-map)# set ip next-hop 13.1.1.2
router(config-if)#ip policy route-map cisco
router#debug ip policy
IP SLA (IP Service level agreement)
it is a track object. this feature allow you to make sure that next hop is reachable befor that the routing table is used.
router(config)#access-list 101 permit ip any 5.5.5.0 0.0.0.255
router(config)#ip sla 10
router(config-ip-sla)#icmp-echo 45.1.1.2 source-ip 24.1.1.1
router(config-ip-sla-echo)#frequency 5 (default 60sec)
router(config)#ip sla schedule 10 start-time now life forever
router(config)#track 100 rtr 10
router(config-track)#delay down 1
router(config-track)#delay up 10
router(config)#route-map cisco permit 10
router(config-route-map)#match ip address 101
router(config-route-map)#set ip next-hop verify-availability 24.1.1.2 5 track 100
router(config-if)#ip policy route-map cisco
how to change bandwidth usage by eigrp (bydefault uses 50%)
router(config-if)# IP bandwidth-percent eigrp 100 10
Frame-relay fullMesh
r1(config-if)#ip address 192.168.1.1 255.255.255.0
r1(config-if)#enacapsulation frame-relay
r1(config-if)#ip address 1.1.1.1 255.255.255.0 (loopback)
r1(config)#router eigrp 100
r1(config-router)#network 0.0.0.0
r1(config-router)#no auto-summary
same configuration on r2,r3,r4
r5(config)#frame-relay switching
r5(config)#interface serial 0/0
r5(config-if)#enacapsulation frame-relay
r5(config-if)#frame-relay intf-type dce
r5(config-if)#clock rate 64000
r5(config-if)#frame-relay route 102 interface serial 0/1 201
r5(config-if)#frame-relay route 103 interface serial 0/2 301
r5(config-if)#frame-relay route 104 interface serial 0/3 401
r5(config)#interface serial 0/1
r5(config)#encapsulation frame-relay
r5(config-if)#frame-relay intf-type dce
r5(config-if)#clock rate 64000
r5(config-if)#frame-relay route 201 interface serial 0/0 102
r5(config-if)#frame-relay route 203 interface serial 0/2 302
r5(config-if)#frame-relay route 204 interface serial 0/3 402
r5(config)#interface serial 0/2
r5(config)#encapsulation frame-relay
r5(config-if)#frame-relay intf-type dce
r5(config-if)#clock rate 64000
r5(config-if)#frame-relay route 301 interface serial 0/0 103
r5(config-if)#frame-relay route 302 interface serial 0/1 203
r5(config-if)#frame-relay route 304 interface serial 0/3 403
r5(config)#interface serial 0/3
r5(config)#encapsulation frame-relay
r5(config-if)#frame-relay intf-type dce
r5(config-if)#clock rate 64000
r5(config-if)#frame-relay route 401 interface serial 0/0 104
r5(config-if)#frame-relay route 402 interface serial 0/1 204
r5(config-if)#frame-relay route 403 interface serial 0/2 304
neighborship will established between neighbor
r5#show frame-relay route
r5#show frame-relay pvc
disable inverse arp
router(config-if)#no frame-relay inverse-arp (disable on all router)
router#clear frame-relay inarp (to clear inverse arp-cache)
how to configure manual mapping
router1(config-if)#frame-relay map ip 192.168.1.2 102 broadcast
hub and spoke topology
router(config)#interface serial 0.0.1 point-to-point
router(config-subif)#ip address 12.1.1.1 255.255.255.0
router(config-subif)#frame-relay interface-dlci owndlci
Named mode Eigrp
Supports both IPv4 and IPv6 EIGRP Can be in different ASes
Better config hierarchy
Wide Metrics, IPv6 VRF Lite, etc
router(config)#router eigrp ccie
router(config--router)# address-family ipv4 autonomous-system 100
router(config-router-af)#network 12.1.1.0 0.0.0.255
router#show ip protocol
router#show ip topology
router#show ip route
router(config-router)#address-family ipv4 autonomous-system 100
router(config-router-af)# af-interface default/ ethernet 1/0
router(config-router-af-interface)#passive-interface
router(config-router-af-interface)#hello-interval 7
router(config-router-af-interface)#hold-interval 15
router(config-router-af-interface)#authentication mode md5
router(config-router-af-interface)#authentication key-chain cisco123
router(config-router-af-interface)#summary-address 10.1.0.0 255.255.252.0
router(config-router)#address-family ipv4 autonomous-system 100
router(config-router-af)# topology base
router(config-router-af-topology)#timers active-time 4min/disable
router(config-router-af-topology)# metric maximum-hop 2
router(config-router-af-topology)#maximum-path 32
router(config-router-af-topology)#variance 2 (1 to 128)
router(config-router-af-topology)#auto-summary
router(config-router-af-topology)#offset-list 1 in 1000
router(config-router-af-topology)#distribute-list acl/prefix/route-map
OSPF Open Shortest Path First
it is a open standard protocol.
It is an IGP Protocol.
it is a link state routing protocol.
first time full update after that partial update.
hop count limit is unlimited.
it uses protocol number 89.
Default administrative distance is 110.
hello timer 10sec, hold time 40.
multicast address 224.0.0.5(for all router), 224.0.0.6(for DRrouter).
it is a classless routing protocol.
bydefault auto-summarization is disabled.
maximum path bydefault 4 (ios 15.0 =32).
it send a update with a sequence number starting from 0x80000001 to 0xffffffff
Types of packet in ospf
Type1 hello
Type2 DBD database discription
Type3 LSR Link state request
Type4 LSU Link state update (retransmission time out 5sec)
Type5 LS Ack link state acknowledge
Note: OSPF header size is 32bytes but always remember that first 24bytes are always common in all packet
OSPF Design:
it reduce the memory and cpu utalization of router
it is easy to solve issues in smaller domain that is area
Area in ospf
Area is a logical group of devices within a single adminstration.
cisco recommond that in single area should not have more than 30 router
area-id is a 32bit long ID.
Area-id can be represnt in decimal number or ipv4 format
Note: inter area route can not move to one area to another area without backbone area, but external route can move one area to another area without backbone area.
Types of Router in OSPF
Backbone router
internal router
Area Border Router
Autonomous System Boundary router
Backbone router
a router has all interfaces in Area 0
we can call it transit area
internal router
A router which has all interfacess in regular Area
ABR Area Border Router
a router which has at least one interface in backbone area and one in regular area
we create ABR for devide database in different area
An ABR will keep multiple Area's database in memory
it can send routing information to different area but not send database
ASBR autonomous system border router
it is used to connect different routing protocol with ospf or redistribute rip,eigrp into ospf
it is used to exchange routing information in ospf and different protocol
Requirement to form ospf neighborship
area-id must match
timers must match
authentication must match
subnetmask must match
stub flag must match
mtu size must match
router-id must not match
network type should match
contents of hello msg
ospf version
area id
router id
network mask
hello interval
chcksum
dead interval
stub flag
priority
authentication type
authentication
designated router
backup designated router
neighbor router id
neigbor router priority
Router-id
router id is a unique ID in a area to identify the database on every router
how to set router id manually
router(config-router)#router-id 1.1.1.1
how to set router-id automatically
highest ip address of loopback interface
highest ip address of physical interface
ospf neighborship states
Formula to calculate total number of adjacancy
when we dont have a DR and BDR N(n-1)/2
when we have both DR and BDR NX2-3
when we have only DR (N-1)
LSA: Link State Advertisement
A router will always keep its route information in its database in the form of LSA, when any update will go from one device to another device it will go in the form of LSA
Types of LSA
Type1 LSA: Router LSA
Type 2 LSA: Network LSA
Type 3 LSA: Summary LSA
Type 4 LSA: ASBR Summary LSA
Type 5 LSA: External LSA
Type 6 LSA: Group Membership LSA
Type 7 LSA: NSSA LSA
Type 8 LSA:
Type 9 LSA:
Type 10 LSA:
Type 11 LSA:
Type1 LSA: Router LSA
It is generate by every router within an area to represent itself, it will not cross its own area
within an area all routers have common 'Router LSA' information,
one router LSA can keep multiple links information
after every 30min router will flood lsa, if any router receives higher sequence no. lsa than router will execute SPF algorithem
in router LSA link-id and advertising router-id will be same
router lsa contain some special bits like 'V' end point of virtual link, 'E' it is ASBR, 'B' it is ABR.
link-id= router id, adv router-id= router-id
Type2 LSA: Network LSA
It is generated by DR router within a segment to represent itself
it is having information that how many devices are connected in that multi-access link network in the form of router-id. it will also having the information of DR router's ip address.
it send to all attached router between the same area
link-id= ip address of DR, adv router-id= router id of DR
Type3 LSA: summary LSA
It is generated by ABR router for sending routing information from one area to another area
it contain information about all inter area routes
link-id=network id (prefix id), adv. router-id= router id of ABR
Type4 LSA: ASBR summary LSA
it is generated by ABR
discribe that who is doing redistribution means ASBR information
cost to reach an ASBR from ABR
Link-id= router-id of ASBR, Adv. router-id= router-id of ABR.
Type5 LSA: External LSA
generated by ASBR
this LSA will keep the information of all routes of other routing domain
link-id= external routes, adv. router-id= router-id of ASBR.
Type7 LSA: NSSA External LSA
It is generated by ASBR within NSSA Area
it remain within the NSSA Area
LSA7 gets translate back into type5 LSA by the NSSA ABR router
link-id= external routes, adv. router-id= router-id of ASBR
how to enable ospf on interface
router(config)#router ospf 100
router(config-router)#network 12.1.1.0 0.0.0.255 area 0
router(config-if)#ip ospf 100 area 1
how to elect DR/BDR on point to point link
router(config-if)#ip ospf network broadcast
how to avoid DR/BDR election on multi-access link
router(config-if)#ip ospf network point-to-point
how to change priority of interface
router(config-if)#ip ospf priority 2 (0-255)
how to adertise loopback on there own prefix length
router(config-if)#ip ospf network point-to-point
how to check ABR router
router#show ip ospf border-router
how to check which interface in which area
router#show ip ospf interface brief
how to check detail of all interface
router#show ip ospf interface
how to configure virtual-link
router(config-router)#area 1 virtual-link 3.3.3.3
redsitribute eigrp into ospf
router(config-router)#redistribute eigrp 100 subnets
redistribute rip into ospf
router(config-router)#redistribute rip subnets
Note: all external route will come as E2 route in ospf and it is larger route than any other path. it will never show total cost of path (cost20)
advance redistribution in ospf (change seed-metric)
router(config-router)#redistribution eigrp 100 subnets metric 30
Note: if cost to reach asbr is same than we can change seed-metric
how to advertise E1 route during redistribution
router(config-router)#redistribution eigrp 100 subnets metric-type 1
how to add tag during redistribution
router(config-router)#redistribution eigrp 100 subnet metric-type 1 tag 11
condition redistribution with using route-map (redistribute specific route)
router(config)#access-list 1 permit 60.1.1.0 0.0.0.255
router(config)#access-list 1 permit 60.1.2.0 0.0.0.255
router(config)#route-map cisco permit 10
router(config-route-map)#match ip address 1
router(config-router)# redistribution eigrp 100 subnet metric metric-type 1 tag 11 route-map cisco
redistribute ospf into eigrp for specific route
router(config)#access-list 1 permit 10.1.1.0 0.0.0.255
router(config)#route-map cisco1 permit 10
router(config-route-map)#match ip address 1
router(config)#router eigrp 100
router(config-router)#redistribution ospf 1 metric 1544 0 255 1 1500 route-map cisco1
Type of Area
Standard Area
Stub Area
Totally Stub Area
NSSA Area
Totally NSSA Area
Note: we used area type to filter LSA
Standard Area:
bydefault all areas are standard area
Stub Area
it is used to filter Type5 LSA and Type4 LSA or to filter external routes
after filtering type5 and type4 LSA It automatically generate default route
default route is advertise by ABR
stub are run on both sides means ABR and all other router of this area.
we cant configure area0 as stub area
stub area not allow virtual-link
stub area is not allowed ASBR router so we cant configure stub area near ASBR router.
we cant make stub to that area which is attached with ASBR bcz it cant do redistribution .
router(config-router)#area 1 stub
Totally stub:
it filter LSA3,4,5 or external as well as inter-area routes
It automatically generate Default route
implement only on ABR router
router(config-router)#area 1 stub no-summary
NSSA Area
it stand for not-so-stub-area
it is used to allow an asbr to send external routes through stub area with using type7 LSA.
filter LSA4,5 but redistribution is allowed
ASBR router will generate type7 LSA after that ABR will convert type 7 lsa back to type5 LSA.
default route will be manully configured
run on both side like stub router
router(config-router)#area 1 nssa
router(config-router)#area 1 nssa default-information originate
Totally NSSA
it filter LSA3,4,5
Default route will automatically generated
implement only on ABR router
allow redistribution
default route originate by ABR
router(config-router)# area 1 nssa no-summary
propogate default-route in ospf with using default-inforation originate command
router(config-router)#default-information originate / metric-type 1
it will propogate befault route if default route is present in it routing table
router(config-router)# default-information originate metric-type 1 always
Route filtering
To filter routes we can use distribute-list. under distribute-list we can call varrious components
Standard ACL
Extended ACL
Prefix-list
Route-MAP
Area Filter List
Note: we cant configure Distribute-list in outbound direction in ospf expect ASBR
Standard ACL
router(config)#access-list 10 deny 100.1.1.0 0.0.0.255
router(config)#access-list 10 permit any
router(config-router)#Distribute-list 10 in
Extended ACL
router(config)# access-list 101 deny ip host 12.1.1.2 172.16.111.0 0.0.0.255
router(config)#access-list 101 permit ip any any
router(config-router)#distribute-list 101 in
Prefix-list
router(config)#ip prefix-list ccie deny 172.16.0.0/16 ge 24 le 24
router(config)#ip prefix-list ccie permit 0.0.0.0/0 le 32
router(config-router)#distribute-list prefix ccie in
Route-Map with specific metric
router(config)#route-map test deny 10
router(config-route-map)#match metric 20
router(config)#route-map test permit 11
router(config-router)#distribute-list route-map test in
route-map
router(config)#access-list 1 permit 10.1.1.0 0.0.0.255
router(config)#route-map cisco deny 10
router(config-route-map)# match ip address 1
router(config-router)#distribute-list route-map cisco in
Filter Route on ASBR for outbound direction
router(config)#access-list 1 deny 100.1.1.0 0.0.0.255
router(config)#access-list 1 permit any
router(config-router)#distribute-list 1 out
Area Filter-list
In Area filter-list we can use only prefix-list
Area filter-list can configure both direction
we can filter inter-area routes
we can filter type3 LSA for a area
we can configure area filter-list on ABR router only
router(config)#ip prefix-list ccie deny 10.1.0.0/16 ge 32 le 32
router(config)#ip prefix-list ccie permit 0.0.0.0/0 le 32
router(config-router)#area 3 filter-list prefix ccie in
or
router(config-router)#area 0 filter-list prefix ccie out
summarization
we can't configure summarization for intra area route
we can configure summarization only on ABR which is generating LSA3 or on ASBR which is generating LSA5.
Types of summarization
Internal (On ABR)
External (On ASBR)
internal summarization
router(config-router)# area 0 range 10.1.0.0 255.255.252.0 (routes of area 0 on R7)
remove null 0 entry for internal summarization
router(config-router)#no discard-route internal
external summarization
router(config-router)# summary-address 1.1.0.0 255.255.252.0
remove null 0 entry for external summarization
router(config-router)#no discard-route external
note: we can configure external summarization on translater also.
filter routes with using internal summarization
router(config-router)# area 2 range 1.1.0.0 255.255.252.0 not-advertise
filter routes with using external summarization
router(config-router)# summary-address 1.1.0.0 255.255.252.0 not-advertise
how to change max-path in ospf
router(config-router)#maximum-path 10
how to change A.D. value in ospf
router(config-router)#distance 100
how to change hello-timer in ospf
router(config-if)#ip ospf 100 hello-interval 5
note: if we changed hello interval than dead timer will automatically get changed. if we changed dead-interval manually than dead will not get change automatically
how to change dead-interval in ospf
router(config-if)#ip ospf 100 dead-interval 15
how to check hello and dead timer in ospf
router# show ip ospf interface serial 0/0
note: if hello and dead timers are mismatch than neighborship will not come up
how to change reference bandwidth in ospf
router(config-router)#auto-cost reference-bandwidth 1000
router#show ip protocol
how to check cost of any interface
router#show ip ospf interface serial 0/0
how to check bandwidth of any interface
router#show interface serial 0/0
how to change cost on any interface
We can change path cost for path manupulation
router(config-if)#ip ospf cost 50
how to set maximum LSA size
router(config-router)#max-lsa 40 / warning-only
authentication in ospf
Type 0 - Null
Type1 - Plain text
Type2 - MD-5
How to configure plain text authentication
router(config-if)# ip ospf authentication (to enable plain text authentication)
router(config-if)#ip ospf authentication-key cisco123
router#debug ip ospf events
how to configure md-5 authentication
router(config-if)# ip ospf authentication message-digest (to enable md-5 authentication)
router(config-if)#ip ospf message-digest-key 1 md5 cisco123
router#debug ip ospf events
how to set null authentication
router(config-if)#ip ospf authentication null
note: we can configure plain text and md5 authentication but at a time latest authentication will work
how to configure authentication globaly
router(config-router)#area 0 authentication message-digest
router(config-if)#ip ospf message-digest-key 1 md5 cisco123
OSPF Network types
we use network types in ospf bcz it depend upon a media
RFC Specific: non broadcast and point to multipoint
Cisco specific: point to point, point to multipoint non broadcast and broadcast
Fully mesh topologies
Broadcast
Non broadcast
Hub & Spoke
p2mp, p2mp-nb, p2p
Non broadcast n/w –
Default n/w type for frame relay (in case of sub-interface multipoint).
Manually specify neigbrship becz it can’t make nbr automatically (hello 30 and dead 120)
next hop can’t change.
Unicast hello send and Can connect more than 2 router but have no broadcast capability.
It elects Dr and BDR but all OSPF packets are exchange through unicast
Command: Int fa0/0
Ip ospf network non-broadcast
Note: Not mandatory to configure static nbrship both side. we can configure only one side
2.Broad cast n/w –
Default n/w on fast Ethernet and FDDI
Will elect DR & BDR
Always map with broadcast keyword otherwise can’t make nbrship.
We can’t able to set nbr manually if we forget to mention broadcast keyword in mapping time.
It use multicast 224.0.0.5 add (with 01005e00005 for all ospf router) 224.0.0.6 for all DR router.
Hello time 10 sec dead 40 sec
To change n/w type
# Int fa0/0
#IP OSPF n/w broad cast
Point to multipoint :-
it is not default option but best choice for nbma n/w, if broadcast is enabled otherwise it can’t work
Does not select DR and BDR packet are multicast 224.0.0.5
Can’t be configured manually assign nbr
Hello time 30 sec dead time 120 sec
/32 will be as entry of all routers as a host.
Point to multipoint non-broadcast:-
Same as point to multipoint but configure with additional non broadcast keyword
No DR/BDR election
Unicast neighbor statement should be configured
The packet is unicast
Hello time 30sec dead time 120sec
Point to point n/w :-
Default for TI, point to point sub interface on frame relay
Hello time 10 sec and dead interval 40.
next hop ip is advertizing router.
No DR and BDR election.
It use multicast add -224.0.0.5
OSPF ignore subnet mask mismatch on point to point link.
6. Loopback:-
1. It is default n/w type for loopback interface
2. OSPF advertise stub n/w as host router /32
7. virtual-link n/w:-
Virtual link is used for non backbone area that is not directly connected with backbone area (area 0).
We always configure a virtual link over a primary address.
This n/w type suppress hello
Transits area means who work between area 0 and any regular area.then we use virtual-link over transits area.
Area 1 virtual- link 146.146.146.6 hello interval 20
# Sh ip os virtual-link
n/w types
Hello times
Dead times
DR & BDR
Auto NBR discovery
Manual nbr define
Broadcast
10
40
Y
Y
X
P2p
10
40
X
Y
X
P2mp
30
120
X
Y
X
NON BROADCAST
30
120
Y
N
Y
P2mp (NB)
30
120
X
N
Y
BGP: Border Gateway Protocol
it is an EGP Protocol (it can form neighborship between two different AS's)
it is a Path Vector routing Protocol (it uses multiple attribute to select best path)
it is highly scalable than IGP (it can have lakhs of routes in its BGP table)
it is reliable protocol (it uses TCP)
it uses tcp port number 179 before establish neighborship it have to form tcp connection (three way hand shake process).
only BGP is fully reliable routing protocol.
it is more secure than any other routing protocol bcz all msgs will travel on TCP protocol
it is a classless routing protocol
it support manual summarization
Administrative Distance: IBGP 200, EBGP 20.
A.S. size is 2bytes(0-65535) and 4bytes(0.0-65535.65535).
Public A.S= 1 to 64511, Private AS=64512 to 65534.
BGP doesn't support dynamic neighbor discovery.
it supports only md5 authentication
bgp convergence is slow as compaire to IGP.
note: we can't configure more than one AS on a single router.
note: BGP sends all type of packets as unicast.
why we use BGP
IGP's were developed for to handling upto 1000 of routes inside their routing table. therefore can't be implement in very large networks.
BGP can contain lakh's of routes inside their BGP table or routing table.
we never use default route in ISP router to other ISP router.
in IGP's if any link (prefix) goes down thn it effects to complete routing structure(topology). but in BGP, it not affects other routers bgp table.
when we are service provider or network size is very large.
when we have multiple connections for internet or multiple service provider.
Types of customers
single homed customer
Dual Homed customer
single multi-homed
Dual multi-homed
single homed customer
single internet connection from ISP
we will never configure BGP in single homed customers.
we configure static default route in the direction of ISP and natting also
Dual homed customer
Two internet connection from same ISP
if we configure default route on both connection than it will not perform load-balancing
to utalize both of connection we use BGP in dual homed customer
Single multi-homed
In this we must have two ISP and customer must have atleast one connection from each ISP.
we can't configure default route so we to configure BGP
Dual multi homed
in this we must have atleast two isp and two link from each isp.
Types of msges in BGP
there is four types of msgs in BGP, each type of BGP packet will travell over TCP. it is not possible to transmit any single msg of BGP without forming TCP connection.
1 OPEN msg
open msg send only once when nbrship comes up. than after BGP will not send any open msg.
open msg will be used by BGP to exchange initial configuration between two bgp peers which is require to form bgp neighorship
contents of bgp
version 4
router-id
own AS
Hold down timer (180sec)
2 keep-alive
After exchanging open msgs successfully between both router, router will start to send keep-alive msgs periodically after every 60sec just to inform its neighbor that im still awake.
if any router doesn't receive keep alive msg from its neighbor within 180sec (hold down time) than router will break down the neighborship
3 Update
update packets will be responsible to carry routes information. update packet having some components
Path Attributes: some crieteria used by selection of best path.
prefix info/NLRI: network layer reachability information.
withdrawn routes: the prefix that goes down.
Note: if any router have multiple prefixes and all prefix attributes are same than router will generate a single update msg
4 Notification
if peering goes down than it will generate notification msg and it will contain the cause of problem.
FSM(finite state mechnism) of BGP / BGP neighborship states
1 Idle: neighbor shutdown / waiting for start 3-way handshake.
2 Connect: try to form TCP connection, but wan't be confirmed
3 Active: TCP connection not completed, retrying to form tcp connection
4 Open-sent: TCP connection completed and sent open msg.
5 Open-confirm: exchanged open msg, perameter agreed, send keep-alive after 60sec
6 Established: peering completed, update is exhanged.
Types of neighbor in BGP
IBGP: Internal border gateway protocol
EBGP: external border gateway protocol
how to establish neighborship in bgp
router#debug ip tcp packet
router#debug ip bgp all
router(config)#router bgp 100
router(config-router)#neighbor 12.1.1.1 remote-as 200
router#show tcp brief
router#show ip bgp neighbor
router#show ip route
router#show ip bgp
how to advertise prefix
router(config)#router bgp 100
router(config-router)#network 172.16.0.0 mask 255.255.0.0
note: we can advertise network but its prefix length should be match in its routing table connected route.
note: it will install only best route of bgp table into routing table.
Well known Mandatory
BGP will always carry these attributes with bgp update automatically
well know discreationary
sometimes bgp will carrry these attribute with bgp update , sometime its not. it depends on nbr, its IBGP nbr or EBGP nbr
optional transitive
if any bgp neighbor receive any update with optional transitive attribute and that router dont support that attribute in that case it will not drop update, it will accept that update and also will forword it to another neighbor after removing that attribute.
optional non-transitive
if any bgp neighbor receive any update with optional non-transitive attribute and that router dont support that attribute in that case it will discard that incoming update.
how BGP define Best Path
1 Next-hop: reachability, if next-hop not reachable than it will not compaire other path attribute, if any router receiving any prefix from two nbr and next-hop is reachable via both router, than bgp will not define best path based on next-hop.
2 weight:
it is cisco proprietory and also it has local significance,
bgp will not carry weight information with bgp update
for self advertised prefixes it is bydefault 32768
for all recieved prefixes bydefault it is 0
higher weight will always preffered.
3 Local preference
bgp will always include local preference attribute in its out going bgp update but only for ibgp neighbor.
bydefault local preference is 100 for internal prefixes
higher will always preffered
if any router receive prefixes from ebgp nbr (0), and from IBGP nbr (100) in that case local preference will never compaire
4 Self Advertised
self advertised prefix will be preferred
if router receiving same prefix from different nbr than it will not compaire self advertised.
5 AS Path
AS- path list can have maximum 64 AS's
router will define that path as best which is providing destination network after crossing less numger of AS
6 Origin code
i = if we are advertising route in bgp with network cmd
E= if any route advertised in EGP.
? = if we redistributed anything in BGP bydefault origin code will be '?'
i>E>?
7 MED (metric)
bedefault med IS 0, lower will always be preferred
if we redistribute any routing protocol into bgp, their metric will go along will bgp update in the form of med.
some time metic will be 0 sometimes null.
8 external>internal
if any prefix coming from to different nbr one is ebgp and one is ibgp than it will preferre external first
9 IGP cost to reach next-hop
if igp configured background of bgp thn bgp can use igp cost to reach next-hop address.
10 oldest path (for ebgp neighbor only)
if router receiving sam eprefix coming from two different EBGP neighbor than oldest path always be preffered
11 router-id of neighbor
lower will always preffered
if router receiving same prefix coming from two different IBGP nbr than lower router-id of neighbor will always be preffered
12 lower neighbor address
if router receiving same prefix coming from two nbr which router id is has same than lower ip address will be preffered
note: BGP support equal cost load-balancing but up to igp cost to reach next hope attribute must be same.
loop avoidance mechenism in BGP
BGP will always discard all these updates which are carrying its own AS inside there AS-path list.
if a BGP router receives anything from one ibgp neighbor than it will never advertise that information toward any other ibgp nbr.
Rule of next-hop
Whenever any router give update to its ebgp neighbor, it will advertise update after modifying their next-hop address.
whenever any router give update to its ibgp neighbor, it will advertise update without modifying their next-hop address.
how to configure neighbor
router(config-router)#neighbor 12.1.1.2 remote-as 100
how to advertise network in bgp
router(config-router)#network 10.1.1.0 mask 255.255.255.0
note: that prefix should be present in its local routing table with same prefix lengh.
connected check rule for EBGP
According to BGP, EBGP neighbor are directly connected
if ebgp neighbor are not directly connect in that case bgp will not initiate bgp neighborship due to directly connected rule.
to break this rule we have to disable connected check rule.
if we change ttl value than directly connected check rule will get disable automatically.
Note: open msg ttl value for ebgp enighbor is 1, and for ibgp neighbor ttl value is 255.
router(config)#router bgp 100
router(config-router)#neighbor 2.2.2.2 remote-as 200
router(config-router)#neighbor 2.2.2.2 update-source loopback 1
router(config-router)#neighbor 2.2.2.2 disable-connected-check
router(config-router)#neighbor 2.2.2.2 ebgp-multihop 2
how to advertise network in bgp
router(config-router)#network 10.1.1.0 mask 255.255.255.0
router(config-router)#network 192.168.101.0 (advertise class full prefix without mask)
router(config-router)#redistribute connected
how to check check that which route is advertising to neighbor router
router# show ip bgp neighbors 192.168.12.1 advertised-routes
router#clear ip bgp * in
how to configure authentication
router(config-router)#neighbor 1.1.1.1 password 5 cisco@123
how to change keep-alive interval and hold time
router(config-router)#timer bgp 50 100 (globly)
router(config-router)#neighbor 192.168.12.2 timers 50 100 (per neighbor)
note: bgp neighbors will negociate lower hold timer
how to configure summarization
router(config-router)#aggregate-address 100.1.0.0 255.255.248.0 summary-only
we use path attribute for path manupulation for outgoing traffic (weight,local prefernce)
how to manupute path with using weight for all prefix
router(config-router)#neighbor 192.168.13.3 weight 1
how to manupute path selection with using weight for particular prefix
router(config)# access-list 1 permit 1.1.1.1 0.0.0.0
router(config)#route-map weight permit 10
router(config-route-map)#match ip address 1
router(config-route-map)#set weight 1
router(config)# route-map weight permit 20
router(config-router)# neighbor 192.168.13.3 route-map weight in
router# clear ip bgp * in
how to manupulate path selection with using local preference
router(config)#access-list 1 permit 1.1.1.1 0.0.0.0
router(config)#route-map lp permit 10
router(config-route-map)#match ip address 1
router(config-route-map)#set weight 1
router(config)#route-map lp permit 20
router(config-router)#neighbor 192.168.13.3 route-map lp in
how to shutdown any neighbor
router(config-router)#neighbor 192.168.12.2 shutdown
how to manupulate path selection with using AS-Path list
specially use this attribute to manupulate in bound traffic
router(config)#access-list 1 permit 1.1.1.1 0.0.0.0
router(config)#route-map as_path permit 10
router(config-route-map)#match ip address 1
router(config-route-map)#set as-path prepend 100 100
router(config)#route-map cisco permit 20
router(config-router)#neighbor 22.1.1.1 route-map as_path in
router#clear ip bgp *
how to manupulate path selection with using origin code
this attribute is also used to manupulate in bound traffic
router1(config)#access-list 1 permit 1.1.1.1 0.0.0.0
router1(config)#route-map as_path permit 10
router1(config-route-map)#match ip address 1
router1(config-route-map)#set origin incomplete
router1(config)#route-map cisco permit 20
router1(config-router)#neighbor 192.168.12.2 route-map as_path in
router1#clear ip bgp *
how to manupulate path selection with using med
this is also used for inbound traffic
router1(config)#access-list 1 permit 1.1.1.1 0.0.0.0
router1(config)#route-map med permit 10
router1(config-route-map)#match ip address 1
router1(config-route-map)#set metric 1
router1(config)#route-map cisco permit 20
router1(config-router)#neighbor 192.168.12.2 route-map med in
router1#clear ip bgp *
note: if any prefix is receiving from 2 different neighbor and both neighbor AS is same than it will compare med. if any prefix is receiving from 2 different neighbor and both neighbor AS is different than it will not compare med (bydefault)
router(config-router)# bgp always-compare-med
note: we cant manupulate path selection with using path-attribut external>internal.
redistribute eigrp into bgp
router(config-router)# redistribute eigrp 100
redistribute bgp into ospf
router(config-router)#redistribute bgp 300 subnets
redistribute ospf into bgp
router(config-router)#redistribute ospf 100 / match internal external
redistribute bgp into eigrp
router(config-router)#redistribute bgp 200 metric 1544 0 255 1 1500
note: bydefault bgp will not redistribute interanl route.
router(config-router)#bgp redistribute-internal
route filtering in bgp
standard ACL
prefix-list
route-map
note: we can't call route-map in distribute-list
route filering with using standard acl
router2(config)# access-list 1 deny 40.1.1.1 0.0.0.0
router2(config)# access-list 1 permit any any
router2(config-router)# distribute-list 1 in
or
router2(config-router)# neighbor 192.168.2.2 distribute-list 1 in
route filtering with using prefix-list
router(config)# ip prefix-list test deny 40.1.0.0/22 ge 32 le 32
router(config)# ip prefix-list test permit 0.0.0.0/0 le 32
router(config-router)# neighbor 192.168.2.2 distribute-list prefix-list test in
route filtering with using route-map
route
ipv6 addressing
it is a 128 bits address and devided into 8block, in each block there is 16bits
it will be represented in hexadecimal form
ipv6 address is devided into two parts, first part known as network prefix, and second part is host-id part.
types of address in ipv6= 1 unicast 2 multicast
unicast: unique local address (fc00::/7), global unicast address (2000::/3), link local add (fe80::/10)
multicast: ff00::/8
loopback address ::1
link-local address
we will never required to allocate link-local address manually
device will automatially calculate these link-local address by itself
link local address can't across its broadcast domain
we can communicate within the network with using this address.
NO ARP
NO need of dhcp server (serverless auto configuration)
ND protocol
this protocol will use icmpv6 to get the mac addrss of dest/next-hop, serverless auto conf, router-discovery, prefix discovery, duplicate address
DAD duplicate address detection
there is no gratious arp, to detect duplicate ip address it uses DAD, and this dad will be also performed with the help of icmpv6.
types of msgs in ipv6
router solicitation:
multicasted by a node when it wants routers to send a router advertisement immediately instead of waiting for advertisement the next scheduled. it send router soliitation to learn about conf parameters and about the existance of routers on the link.
router advertisement
sent periodically or in reponse of a soliitation. routers advertise their presence, as well as provide information neccessory for a node to configure itself. (gatgeway info,prefix info)
neighbor solicitation
it is like arp req msg, to get layer2 address of neighbor, determine whether the neighbor is still reachable via layer2 address, to check duplicate address.
neighbor advertisement
it is like ARP response msg, to give layer 2 address.
redirect
if there is two different prefix and they will communiate via router so after redirect msg they will communicate directly
ipv4 224.0.0.1 for all node, 224.0.0.2 for all routers only
ipv6 ff02::1 for all node, ff02::2 for all routers only.
rip ff02::9
ospf ff02::5/6
eigrp ff02::A
for stateless auto config
router(config-if)# ipv6 address autoconfig
router(config-if)# ipv6 address autoconfig default (to receive default route automatically)
RIP:ex
we can use offset-list in rip (config-if)#ipv6 rip test metric-offset 3)
rip supports only prefix list for route filtering
BGP
router(config)#ipv6 unicast-routing
router(config)#router bgp 100
router(config-router)# bgp router-id 1.1.1.1
router(config-router)#neighbor 2000:192:168:1::2 remote-as 200
router(config-router)# no bgp default ipv4-unicast
router(config-router)#address-family ipv6 unicast
router(config-router)#neighbor 2000:192:168:1::2 activate
router#show ipv6 unicast summary
GRE: Generic router encapsulation
it is a layer 3 protocol
it uses protocol number 47
it will add 24byte long extra information (external ip header 20bytes, type and flag 4bytes )
compatability between ipv4 and ipv6
Dual stacking
ipv6 tunnel
NAT-PT
r2(config)#ip route 1.1.1.0 255.255.255.0 serial 0/0
r3(config)# ipv6 route ::/0 serial 0/0
r2(config-if)# ipv6 nat (serial 0/0)
r2(config-if)#ipv6 nat (serial 0/1)
r2(config)# ipv6 nat prefix 2000::/96
r2(config)#ipv6 nat v6v4 source 2000:192:168:2:2 12.1.1.3
r2(config)# ipv6 nat v4v6 source 1.1.1.1 2000::0101:0101
GRE Generic router encapsulation
layer 3 protocol
protocol number is 47
will directly intract with ip itself
it will add 24byte long extra information
24byte= 20byte for external ip header, 4byte will be for type and flags field.
DMVPN
NHS: ROUTER(CONFIG)# interface tunnel 1
router(config-if)#ip address 192.168.1.1 255.255.255.0
router(config-if)# tunnel source serial 1/0
router(config-if)#tunnel mode gre multipoint
router(config-if)#ip nhrp network-id 1 (any number)
router(config-if)#ip nhrp authentication cisco123
router(config-if)#ip nhrp map
NHC:
router(config)#interface tunnel 1
router(config-if)#ip address 192.168.1.2 255.255.255.0
router(config-if)#tunnel source serial 1/0
rotuer(config-if)#tunnel destination (ip address of nhs)
rotuer(config-if)#ip nhrp network-id 10
rotuer(config-if)#ip nhrp authentication cisco123
rotuer(config-if)#ip nhrp map 192.168.1.1 (nhs tunnel ip address.) 11.1.1.10 (public ip of nhs)
rotuer(config-if)#ip nhrp nhs 192.168.1.1
rotuer#show ip nhrp
after configuring eigrp
nhs(config-if)# ip nhrp map multicast dynamic
nhc(config-if)#ip nhrp map multicast 11.1.1.1 (public ip of nhs)
nhc(config-if)#shutdown / no shutdown
AAA (authorization)
priviledge level (default 0,1,15)
r(config)#username cisco privilege 5 password cisco
r(config)#username test privilege 15 password test
r(config-line)#login local
login with cisco user
it can run only limited commands.
now login with test user which has privilege 15 and give the privilege to user cisco.
r(config)#privilege exec level 5 configure terminal
r(config)#privilege configure level 5 interface
r(config)#privelege interface level 5 ip address
r(config)#privilege interface level 5 shutdown
r(config)#privilege interface level 5 no shutdown
r# show privilege
syslog server
r(config)#loggin console ?
r(config)#loggin moniter ?
r(config)#logging host 192.168.1.1 transport udp port 656
r(config)#logging source-interface loopback 1
r(config)#logging rate-limit console all 2
snmp server
r(config)#snmp-server host 192.168.1.1 cisco@123
r(config)#snmp-server community cisco@123 rw
r(config)#snmp-server enable traps
chck in running config
r(config-if)#no snmp trap link-status