[ 1224.156094][T11109] Could not find device with ifindex 2000 in netnsfd 11
[ 1224.156899][T11109] Could not find netns with fd: 2000
[ 1224.157513][T11109] Cannot link a netdevsim to itself
[ 1224.158194][T11109] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).