Docker /etc/hosts and DNS is not what we want #14633
Description
I noticed this earlier and can not explain it:
root@kubernetes-minion-gn8a:/home/thockin# cat /etc/resolv.conf
domain c.thockin-dev.internal.
search c.thockin-dev.internal. 844790599918.google.internal. google.internal.
nameserver 169.254.169.254
nameserver 10.240.0.1
root@kubernetes-minion-gn8a:/home/thockin# nslookup 10.244.2.6 10.0.0.10
Server: 10.0.0.10
Address: 10.0.0.10#53
** server can't find 6.2.244.10.in-addr.arpa.: NXDOMAIN
root@kubernetes-minion-gn8a:/home/thockin# nslookup 10.244.2.6 169.254.169.254
Server: 169.254.169.254
Address: 169.254.169.254#53
** server can't find 6.2.244.10.in-addr.arpa.: NXDOMAIN
root@kubernetes-minion-gn8a:/home/thockin# nslookup 10.244.2.6 10.240.0.1
Server: 10.240.0.1
Address: 10.240.0.1#53
** server can't find 6.2.244.10.in-addr.arpa.: NXDOMAIN
but
root@kubernetes-minion-gn8a:/home/thockin# docker run -ti busybox
/ # nslookup 10.244.2.6 10.0.0.10
Server: 10.0.0.10
Address 1: 10.0.0.10
Name: 10.244.2.6
Address 1: 10.244.2.6 k8s_POD-7be6d81d_hostnames-ctfjl_default_abdc3cba-58d4-11e5-9447-42010af0f439_85570955
/ # nslookup 10.244.2.6 169.254.169.254
Server: 169.254.169.254
Address 1: 169.254.169.254 metadata.google.internal
Name: 10.244.2.6
Address 1: 10.244.2.6 k8s_POD-7be6d81d_hostnames-ctfjl_default_abdc3cba-58d4-11e5-9447-42010af0f439_85570955
/ # nslookup 10.244.2.6 8.8.8.8
Server: 8.8.8.8
Address 1: 8.8.8.8 google-public-dns-a.google.com
Name: 10.244.2.6
Address 1: 10.244.2.6 k8s_POD-7be6d81d_hostnames-ctfjl_default_abdc3cba-58d4-11e5-9447-42010af0f439_85570955
/ # nslookup 10.244.2.6 127.0.0.1
Server: 127.0.0.1
Address 1: 127.0.0.1 localhost
Name: 10.244.2.6
Address 1: 10.244.2.6 k8s_POD-7be6d81d_hostnames-ctfjl_default_abdc3cba-58d4-11e5-9447-42010af0f439_85570955
What is happening here? Is it docker? The same doesn't seem to happen in ubuntu.
root@kubernetes-minion-gn8a:/home/thockin# docker run -ti ubuntu
root@52401dfed17a:/# apt-get update > /dev/null
root@52401dfed17a:/# yes | apt-get -y install dnsutils > /dev/null
root@52401dfed17a:/# nslookup 10.244.2.6 10.0.0.10
Server: 10.0.0.10
Address: 10.0.0.10#53
** server can't find 6.2.244.10.in-addr.arpa: NXDOMAIN
root@52401dfed17a:/# nslookup 10.244.2.6 169.254.169.254
Server: 169.254.169.254
Address: 169.254.169.254#53
** server can't find 6.2.244.10.in-addr.arpa: NXDOMAIN
We need to understand this ASAP. Docker is version 1.8.2