[ 1187.235482][T10975] Could not find device with ifindex 2000 in netnsfd 11
[ 1187.236196][T10975] Could not find netns with fd: 2000
[ 1187.236758][T10975] Cannot link a netdevsim to itself
[ 1187.237417][T10975] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).