OpenVPN client maintenance

disable_openvpn_client_dns.sh

A companion to install_openvpn_client_centos7.sh for hosts where the VPN should keep tunneling traffic but must stop forcing its own DNS (e.g. 10.7.7.53). It backs up the client config, comments out the DNS hooks, restarts the service, and can optionally write your own resolvers via --set-dns. Idempotent and reversible.

ワンライナー

curl -fsSL helper.sh/disable_openvpn_client_dns.sh | sudo bash

curl -fsSL helper.sh/disable_openvpn_client_dns.sh | sudo bash -s -- --set-dns "114.114.114.114 223.5.5.5"

生ファイル

生スクリプト

Bundled in this site

実行条件

CentOS 7 (or compatible)
root privileges or sudo
An existing client config at /etc/openvpn/client/client.conf

適用場面

Keep the VPN tunnel up but stop it from forcing an internal DNS like 10.7.7.53
Restore your own public resolvers on a host that does not need *.internal name resolution
Undo the DNS hooks added by install_openvpn_client_centos7.sh without reinstalling

主なポイント

Backs up client.conf to a timestamped .bak before changing anything
Comments out script-security / up / down DNS hooks (idempotent, safe to re-run)
Restarts openvpn-client@client so the change takes effect immediately
Optional --set-dns "ns1 ns2" writes /etc/resolv.conf for you
Supports --config-dir / --config-name for non-default install locations
Reversible: remove the leading # from the hooks and restart to re-enable

推奨手順

Run the one-liner with sudo or as root on the host where OpenVPN client is already installed.
The script backs up client.conf, comments out the DNS hooks, and restarts openvpn-client@client.
If you did not pass --set-dns, edit /etc/resolv.conf yourself to point at your preferred resolvers.
Verify with cat /etc/resolv.conf, and confirm the tunnel still works with ping to an internal IP.

注意事項

After disabling the VPN DNS, internal names (e.g. *.reshub.cn) will no longer resolve unless you keep that resolver another way.
A timestamped client.conf backup is created automatically; keep it until you confirm the change is correct.
--set-dns overwrites /etc/resolv.conf entirely, so list every nameserver you need.