nmupdate

Because NetworkManager on Ubuntu is broken-

This application is a replacement for DNS search management for VPN tunnels on Ubuntu where NetworkManager is broken.

this application only handles DNS search on ipv4 (ipv4.dns.search) and is designed to transparantly reload the whitelist on change.

It does this by listening for FileSystem events made against the config file. It also re-scans the network interfaces once a second to ensure changes are applied as soon as tunnels come up.

Installation

Bunch of manual steps

• Build the binary (go build .)
• Copy to /usr/local/bin
• Setup a config file in /etc/nmupdate/whitelist.yaml (see below)
• Set up a systemd file

whitelist.yaml

# takes precedence over tunnels
tunnelPrefix: tun

# Do not specify tunnels if tunnelPrefix above is specified
# tunnels []

# A list of hosts to add to dns-search
whitelist:
  - example.com
  - example.net
  - example.social

Systemd sample file

[Unit]
Description=Automatically handle tunnel DNS entries
After=network.target

[Service]
ExecStart=/usr/local/bin/nmupdate -config /etc/nmupdate/whitelist.yaml
ExecReload=/bin/kill -HUP $MAINPID
Restart=on-failure
RestartForceExitStatus=SIGPIPE
KillMode=control-group

[Install]
WantedBy=multi-user.target