The change applies to GetNetDevsWithPredicate. The function calls
FindNetDevs which already does the same filtering.
The change prevents from "container-addrs" (weaveutil) returning
"unable to open X process namespace" error which happens when
a container dies while the cmd is being executed.
Make sure that any network namespace changes happens at the end of
the cmd invocation. Otherwise, we are risking to end up in a situation
in which OS scheduling threads are in a "wrong" namespace.
See WithNetNS for more details.
- Optimize. Use LinkByName instead of iterating over list of available
links. Linux does not support interfaces with the same names.
- Remove unnecessary indirection in utility functions which return
common.NetDev.
Also move netlink and netns code from common to net
Creates interface if not already there
Adds addresses
Move the set link 'up' to after addresses are added
Martynas Pumputis