[   31.157351][  T228] Could not find device with ifindex 2000 in netnsfd 11
[   31.158419][  T228] Could not find netns with fd: 2000
[   31.159321][  T228] Cannot link a netdevsim to itself
[   31.160471][  T228] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).