[ 1229.315293][T11124] Could not find device with ifindex 2000 in netnsfd 11
[ 1229.316132][T11124] Could not find netns with fd: 2000
[ 1229.316825][T11124] Cannot link a netdevsim to itself
[ 1229.317568][T11124] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).