[ 1081.947428][T11093] Could not find device with ifindex 2000 in netnsfd 11
[ 1081.948478][T11093] Could not find netns with fd: 2000
[ 1081.949400][T11093] Cannot link a netdevsim to itself
[ 1081.950667][T11093] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).