[ 1231.204000][T11130] Could not find device with ifindex 2000 in netnsfd 11
[ 1231.204741][T11130] Could not find netns with fd: 2000
[ 1231.205325][T11130] Cannot link a netdevsim to itself
[ 1231.206272][T11130] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).