[ 1214.556522][T11119] Could not find device with ifindex 2000 in netnsfd 11
[ 1214.557240][T11119] Could not find netns with fd: 2000
[ 1214.557788][T11119] Cannot link a netdevsim to itself
[ 1214.558661][T11119] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).