[ 1219.969524][T11251] Could not find device with ifindex 2000 in netnsfd 11
[ 1219.970628][T11251] Could not find netns with fd: 2000
[ 1219.982116][T11251] Cannot link a netdevsim to itself
[ 1219.982844][T11251] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).