[ 1239.555957][T10969] Could not find device with ifindex 2000 in netnsfd 11
[ 1239.556720][T10969] Could not find netns with fd: 2000
[ 1239.557271][T10969] Cannot link a netdevsim to itself
[ 1239.558250][T10969] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).