[ 1219.679029][T11117] Could not find device with ifindex 2000 in netnsfd 11
[ 1219.679750][T11117] Could not find netns with fd: 2000
[ 1219.680280][T11117] Cannot link a netdevsim to itself
[ 1219.681284][T11117] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).