[ 1223.977671][T11125] Could not find device with ifindex 2000 in netnsfd 11
[ 1223.978526][T11125] Could not find netns with fd: 2000
[ 1223.979289][T11125] Cannot link a netdevsim to itself
[ 1223.980082][T11125] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).