[ 1081.704251][T11100] Could not find device with ifindex 2000 in netnsfd 11
[ 1081.705044][T11100] Could not find netns with fd: 2000
[ 1081.705700][T11100] Cannot link a netdevsim to itself
[ 1081.706454][T11100] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).