title: How to identify orphaned veth interfaces and how to delete them?
body: <p>When I start any container by <code>docker run</code>, we get a new <a href="https://github.com/emccode/training/tree/master/docker-hackday/docker-networking-lab-101#v-eth-pairs" rel="noreferrer">veth interface</a>. After deleting container, veth interface which was linked with container should be removed. However, sometimes it's fail ( oftern then container started with errors):</p>
  
  <pre><code>root@hostname /home # ifconfig | grep veth | wc -l
  53
  root@hostname /home # docker run -d -P  axibase/atsd -name axibase-atsd-
  28381035d1ae2800dea51474c4dee9525f56c2347b1583f56131d8a23451a84e
  Error response from daemon: Cannot start container 28381035d1ae2800dea51474c4dee9525f56c2347b1583f56131d8a23451a84e: iptables failed: iptables --wait -t nat -A DOCKER -p tcp -d 0/0 --dport 33359 -j DNAT --to-destination 172.17.2.136:8883 ! -i docker0: iptables: No chain/target/match by that name.
   (exit status 1)
  root@hostname /home # ifconfig | grep veth | wc -l
  55
  root@hostname /home # docker rm -f 2838
  2838
  root@hostname /home # ifconfig | grep veth | wc -l
  55
  </code></pre>
  
  <p>How I can identify which interfaces are linked with existing containers, and how I can remove extra interface which was linked with removed contrainers?</p>
  
  <p>This way doesn't work (by root):</p>
  
  <pre><code>ifconfig veth55d245e down
  brctl delbr veth55d245e
  can't delete bridge veth55d245e: Operation not permitted
  </code></pre>
  
  <p>Extra interfaces now defined by transmitted traffic (if there are no activity, it's extra interface).</p>
  
  <p><strong>UPDATE</strong></p>
  
  <pre><code>root@hostname ~ # uname -a
  Linux hostname 3.13.0-53-generic #89-Ubuntu SMP Wed May 20 10:34:39 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
  
  root@hostname ~ # docker info
  Containers: 10
  Images: 273
  Storage Driver: aufs
   Root Dir: /var/lib/docker/aufs
   Backing Filesystem: extfs
   Dirs: 502
   Dirperm1 Supported: false
  Execution Driver: native-0.2
  Logging Driver: json-file
  Kernel Version: 3.13.0-53-generic
  Operating System: Ubuntu 14.04.2 LTS
  CPUs: 8
  Total Memory: 47.16 GiB
  Name: hostname
  ID: 3SQM:44OG:77HJ:GBAU:2OWZ:C5CN:UWDV:JHRZ:LM7L:FJUN:AGUQ:HFAL
  WARNING: No swap limit support
  
  root@hostname ~ # docker version
  Client version: 1.7.1
  Client API version: 1.19
  Go version (client): go1.4.2
  Git commit (client): 786b29d
  OS/Arch (client): linux/amd64
  Server version: 1.7.1
  Server API version: 1.19
  Go version (server): go1.4.2
  Git commit (server): 786b29d
  OS/Arch (server): linux/amd64
  </code></pre>