[ 1225.963135][T11123] Could not find device with ifindex 2000 in netnsfd 11
[ 1225.963898][T11123] Could not find netns with fd: 2000
[ 1225.969590][T11123] Cannot link a netdevsim to itself
[ 1225.970474][T11123] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).