[ 1240.743861][T11256] Could not find device with ifindex 2000 in netnsfd 11
[ 1240.744618][T11256] Could not find netns with fd: 2000
[ 1240.745199][T11256] Cannot link a netdevsim to itself
[ 1240.745911][T11256] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).