[ 1237.133406][T11114] Could not find device with ifindex 2000 in netnsfd 11
[ 1237.134219][T11114] Could not find netns with fd: 2000
[ 1237.134862][T11114] Cannot link a netdevsim to itself
[ 1237.135596][T11114] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).