[ 1100.137547][T11106] Could not find device with ifindex 2000 in netnsfd 11
[ 1100.138279][T11106] Could not find netns with fd: 2000
[ 1100.138884][T11106] Cannot link a netdevsim to itself
[ 1100.139589][T11106] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).