[ 1213.645650][T11115] Could not find device with ifindex 2000 in netnsfd 11
[ 1213.646730][T11115] Could not find netns with fd: 2000
[ 1213.647676][T11115] Cannot link a netdevsim to itself
[ 1213.649092][T11115] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).