Red Hat Bugzilla – Bug 1251538
[RFE] Allow docker to report the veth interface used by a container
Last modified: 2016-06-03 15:02:34 EDT
Proposed title of this feature request Allow easy discovery of which veth interface a given container is using. What is the nature and description of the request? Currently there is not a reliable and easy way to determine which veth interface a container is using. Docker inspect will report the bridge and other networking information, but reporting which veth interface is in use directly would be beneficial. Why does the customer need this? (List the business requirements here) In their own words: "We're trying to use tc and netem in conjunction with docker containers to create self-contained "nightmare networks" for code testing purposes." How would the customer like to achieve this? (List the functional requirements here) Being able to retrieve this from a 'docker inspect' would be acceptable. Is there already an existing RFE upstream or in Red Hat Bugzilla? No Does the customer have any specific time-line dependencies and which release would they like to target (i.e. RHEL5, RHEL6)? No List any affected packages or components. docker
Issue opened upstream. https://github.com/docker/docker/issues/17064 Shishir
https://github.com/docker/docker/pull/16729 is also related.
Shishir what do you think of https://github.com/docker/docker/pull/16729#issuecomment-145259919
Pretty sure a PR based on https://github.com/docker/docker/pull/16729#issuecomment-145259919 would be good to re-start the discussion (it doesn't seem a big patch)
Asked upstream to include the veth name here https://github.com/docker/docker/pull/18559#issuecomment-164139816
Since this is merged can we close this as fixed in docker-1.10?
It didn't end up in that PR upstream. I'll work out a patch tomorrow and send it upstream.
no plan in docker upstream to expose veths (veth's names generation now lives in libcontainer also). Work should start in libnetwork first. libnetwork maintainers wish to have a generalized way to expose additional data for network drivers (no sense to expose veth names if using OVS driver was their argument) After that it will be exposed in docker inspect
Jake, one possible way of getting the veth used by a container is (this is fine when using the bridge network driver, which is the default and I'm assuming you need this): $ sudo docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 08b1a5b42aa9 nginx "nginx -g 'daemon off" 2 hours ago Up 2 hours 443/tcp, 0.0.0.0:8090->80/tcp elated_euler $ sudo docker inspect --format='{{.NetworkSettings.SandboxKey}}' 08b1a5b42aa9 /var/run/docker/netns/aea8f5968946 $ sudo nsenter --net=/var/run/docker/netns/aea8f5968946 ethtool -S eth0 NIC statistics: peer_ifindex: 308 $ sudo ip link | grep 308: 308: vetha0c705b: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP mode DEFAULT group default They're still not interested in exposing this in docker inspect because it breaks the abstraction built on network drivers.