[ 1229.115936][T11118] Could not find device with ifindex 2000 in netnsfd 11
[ 1229.116689][T11118] Could not find netns with fd: 2000
[ 1229.117407][T11118] Cannot link a netdevsim to itself
[ 1229.118500][T11118] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).