[ 1091.718891][T10978] Could not find device with ifindex 2000 in netnsfd 11
[ 1091.719633][T10978] Could not find netns with fd: 2000
[ 1091.720244][T10978] Cannot link a netdevsim to itself
[ 1091.721308][T10978] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).