(classic)liu-xiao-guo@localhost:~$ sudo apt-get update
Err:1 http://localhost:9999/ubuntu-ports xenial InRelease
Could not connect to localhost:9999 (127.0.0.1). - connect (111: Connection refused) [IP: 127.0.0.1 9999]
Err:2 http://localhost:9999/ubuntu-ports xenial-updates InRelease
Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
Err:3 http://localhost:9999/ubuntu-ports xenial-backports InRelease
Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
Err:4 http://localhost:9999/ubuntu-ports xenial-security InRelease
Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
Reading package lists... Done
W: Failed to fetch http://localhost:9999/ubuntu-ports/dists/xenial/InRelease Could not connect to localhost:9999 (127.0.0.1). - connect (111: Connection refused) [IP: 127.0.0.1 9999]
W: Failed to fetch http://localhost:9999/ubuntu-ports/dists/xenial-updates/InRelease Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
W: Failed to fetch http://localhost:9999/ubuntu-ports/dists/xenial-backports/InRelease Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
W: Failed to fetch http://localhost:9999/ubuntu-ports/dists/xenial-security/InRelease Unable to connect to localhost:9999: [IP: 127.0.0.1 9999]
W: Some index files failed to download. They have been ignored, or old ones used instead.