[ 1232.258149][T10974] Could not find device with ifindex 2000 in netnsfd 11
[ 1232.259242][T10974] Could not find netns with fd: 2000
[ 1232.260130][T10974] Cannot link a netdevsim to itself
[ 1232.261591][T10974] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).