[ 1222.909647][T11126] Could not find device with ifindex 2000 in netnsfd 11
[ 1222.910355][T11126] Could not find netns with fd: 2000
[ 1222.910927][T11126] Cannot link a netdevsim to itself
[ 1222.911617][T11126] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).