[ 1224.733187][T11126] Could not find device with ifindex 2000 in netnsfd 11
[ 1224.734372][T11126] Could not find netns with fd: 2000
[ 1224.735294][T11126] Cannot link a netdevsim to itself
[ 1224.736309][T11126] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).