[ 1221.514327][T11118] Could not find device with ifindex 2000 in netnsfd 11
[ 1221.515044][T11118] Could not find netns with fd: 2000
[ 1221.515581][T11118] Cannot link a netdevsim to itself
[ 1221.516267][T11118] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).