[ 1089.530691][T10965] Could not find device with ifindex 2000 in netnsfd 11
[ 1089.531791][T10965] Could not find netns with fd: 2000
[ 1089.532419][T10965] Cannot link a netdevsim to itself
[ 1089.533165][T10965] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).