Sometimes inspecting a container fails with "Unknown device" #18194
Description
From time to time, this shows up when I try to inspect a container:
Handler for GET /v1.15/containers/<container id>/json returned error: Unknown device bfbc9c7d7c9b5d0d3c6c74a4ebdf9f4d2c19c87d8853ee15d452b7029f20e026
And the inspect fails with a 500 error.
This happens on CentOS 7 on Rackspace Cloud Servers:
# uname -a
Linux acceptance-test-jeanpaul-0 3.10.0-229.11.1.el7.x86_64 #1 SMP Thu Aug 6 01:06:18 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
# docker version
Client:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5
Built: Fri Nov 20 13:25:01 UTC 2015
OS/Arch: linux/amd64
Server:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5
Built: Fri Nov 20 13:25:01 UTC 2015
OS/Arch: linux/amd64
# docker info
Containers: 5
Images: 39
Server Version: 1.9.1
Storage Driver: devicemapper
Pool Name: docker-202:1-919278-pool
Pool Blocksize: 65.54 kB
Base Device Size: 107.4 GB
Backing Filesystem:
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 714 MB
Data Space Total: 107.4 GB
Data Space Available: 38.26 GB
Metadata Space Used: 1.753 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.146 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.93-RHEL7 (2015-01-28)
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 3.10.0-229.11.1.el7.x86_64
Operating System: CentOS Linux 7 (Core)
CPUs: 8
Total Memory: 7.389 GiB
Name: acceptance-test-jeanpaul-0
ID: AS27:V5CG:JJKM:ZMDR:K5E6:SWNJ:7TA6:KWMP:EBYV:YQA6:X2C7:NH2B
WARNING: bridge-nf-call-iptables is disabled
WARNING: bridge-nf-call-ip6tables is disabled
and on CentOS 7 on Amazon EC2:
# uname -a
Linux ip-172-31-24-158 3.10.0-229.14.1.el7.x86_64 #1 SMP Tue Sep 15 15:05:51 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
# docker info
Containers: 0
Images: 40
Server Version: 1.9.1
Storage Driver: devicemapper
Pool Name: docker-202:1-25568900-pool
Pool Blocksize: 65.54 kB
Base Device Size: 107.4 GB
Backing Filesystem: xfs
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 782.5 MB
Data Space Total: 107.4 GB
Data Space Available: 6.39 GB
Metadata Space Used: 1.81 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.146 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.93-RHEL7 (2015-01-28)
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 3.10.0-229.14.1.el7.x86_64
Operating System: CentOS Linux 7 (Core)
CPUs: 2
Total Memory: 6.897 GiB
Name: ip-172-31-24-158
ID: G352:6B3C:BECE:Y3ZK:K3PU:L5TL:ZNTR:NB26:UZM3:ZMSU:4D4X:UBSF
[root@ip-172-31-24-158 ~]# docker version
Client:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5
Built: Fri Nov 20 13:25:01 UTC 2015
OS/Arch: linux/amd64
Server:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5
Built: Fri Nov 20 13:25:01 UTC 2015
OS/Arch: linux/amd64
#
and on CentOS 7 running with Vagrant/VirtualBox (the specific details of which I don't have handy at this particular moment).