CentOS7 重启gitlab nginx

安装完gitlab-ce后出现的问题，原VPS上的LNMP 的nginx被强制停止，端口冲突。解决方法，停止 gitlab之后修改 gitlab自带的nginx的端口？

[root@linode nginx]# gitlab-ctl stop
ok: down: gitlab-git-http-server: 1s, normally up
ok: down: logrotate: 0s, normally up
ok: down: nginx: 1s, normally up
ok: down: postgresql: 0s, normally up
ok: down: redis: 0s, normally up
ok: down: sidekiq: 0s, normally up
ok: down: unicorn: 0s, normally up
[root@linode nginx]# systemctl status nginx
nginx.service - nginx - high performance web server
   Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled)
   Active: failed (Result: exit-code) since 二 2015-11-10 21:53:18 CST; 19min ago
     Docs: http://nginx.org/en/docs/
  Process: 4246 ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf (code=exited, status=1/FAILURE)
  Process: 4243 ExecStartPre=/usr/sbin/nginx -t -c /etc/nginx/nginx.conf (code=exited, status=0/SUCCESS)

11月 10 21:53:15 linode nginx[4243]: nginx: configuration file /etc/nginx/nginx.conf test is successful
11月 10 21:53:15 linode nginx[4246]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
11月 10 21:53:16 linode nginx[4246]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
11月 10 21:53:16 linode nginx[4246]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
11月 10 21:53:17 linode nginx[4246]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
11月 10 21:53:17 linode nginx[4246]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
11月 10 21:53:18 linode nginx[4246]: nginx: [emerg] still could not bind()
11月 10 21:53:18 linode systemd[1]: nginx.service: control process exited, code=exited status=1
11月 10 21:53:18 linode systemd[1]: Failed to start nginx - high performance web server.
11月 10 21:53:18 linode systemd[1]: Unit nginx.service entered failed state.
[root@linode nginx]# systemctl restart nginx