[ 1223.164218][T11114] Could not find device with ifindex 2000 in netnsfd 11
[ 1223.164919][T11114] Could not find netns with fd: 2000
[ 1223.165568][T11114] Cannot link a netdevsim to itself
[ 1223.166361][T11114] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).