[ 1083.368623][T11101] Could not find device with ifindex 2000 in netnsfd 11
[ 1083.369896][T11101] Could not find netns with fd: 2000
[ 1083.370503][T11101] Cannot link a netdevsim to itself
[ 1083.371254][T11101] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).