에이전트 삭제 후 적절한 업데이트가 불가능합니다.

192.168.40.97:3142사용 중인 적절한 캐시 서버가 설치되어 있습니다 apt-cacher-ng. 내 노트북에서 사용하기 위해 다음 내용이 포함된 파일을 디렉토리에 추가했습니다 02proxy./etc/apt/apt.conf.d

Acquire::http { Proxy "http://192.168.40.97:3142"; };

그런데 서버에 문제가 있어서 프록시 없이 apt를 사용하고 싶습니다. 그래서 파일을 삭제 02proxy하고 시도해봤습니다 apt update. 하지만 여전히 서버에 연결을 시도하고 있습니다.

r2m@ssl-60:/etc/apt/apt.conf.d$ sudo apt update
Err:1 http://in.archive.ubuntu.com/ubuntu xenial InRelease
  Could not connect to 192.168.40.97:3142 (192.168.40.97). - connect (111:     Connection refused)
Err:2 http://in.archive.ubuntu.com/ubuntu xenial-updates InRelease
  Unable to connect to 192.168.40.97:3142:
Err:3 http://in.archive.ubuntu.com/ubuntu xenial-backports InRelease
  Unable to connect to 192.168.40.97:3142:
Err:4 http://security.ubuntu.com/ubuntu xenial-security InRelease
  Could not connect to 192.168.40.97:3142 (192.168.40.97). - connect (111: Connection refused)
Reading package lists... Done                   
Building dependency tree       
Reading state information... Done
6 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/xenial/InRelease  Could not connect to 192.168.40.97:3142 (192.168.40.97). - connect (111: Connection refused)
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/xenial-updates/InRelease  Unable to connect to 192.168.40.97:3142:
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/xenial-backports/InRelease  Unable to connect to 192.168.40.97:3142:
W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/xenial-security/InRelease  Could not connect to 192.168.40.97:3142 (192.168.40.97). - connect  (111: Connection refused)
W: Some index files failed to download. They have been ignored, or old ones used instead.

프록시를 삭제하려면 어떻게 해야 합니까? 우분투 16.04에서 사용하고 있어요

Linux ssl-60 4.10.0-42-generic #46~16.04.1-Ubuntu SMP Mon Dec 4 15:57:59 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux