[ 1078.248373][T11106] Could not find device with ifindex 2000 in netnsfd 11
[ 1078.249122][T11106] Could not find netns with fd: 2000
[ 1078.249703][T11106] Cannot link a netdevsim to itself
[ 1078.250432][T11106] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).