[ 1224.128567][T11124] Could not find device with ifindex 2000 in netnsfd 11
[ 1224.129317][T11124] Could not find netns with fd: 2000
[ 1224.129936][T11124] Cannot link a netdevsim to itself
[ 1224.130688][T11124] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).