[ 1197.464177][T10991] Could not find device with ifindex 2000 in netnsfd 11
[ 1197.465566][T10991] Could not find netns with fd: 2000
[ 1197.466155][T10991] Cannot link a netdevsim to itself
[ 1197.466842][T10991] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).