[ 1237.534160][T11125] Could not find device with ifindex 2000 in netnsfd 11
[ 1237.534893][T11125] Could not find netns with fd: 2000
[ 1237.535457][T11125] Cannot link a netdevsim to itself
[ 1237.536448][T11125] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).