Thanks to Keith which answered a Question on Discord.
Start by going to xx network Wallet > Staking > Account actions and press Stop
to the right of the stash account.
On the node computer …
$ sudo systemctl stop xxnetwork-cmix
$ sudo systemctl stop xxnetwork-chain
On the gateway computer …
$ sudo systemctl stop xxnetwork-gateway
$ sudo systemctl stop xxnetwork-chain
Since maintenance often requires rebooting, you will also want to temporarily disable the services so they do not start again each time you reboot. So additionally run …
On the node computer …
$ sudo systemctl disable xxnetwork-cmix
$ sudo systemctl disable xxnetwork-chain
On the gateway computer …
$ sudo systemctl disable xxnetwork-gateway
$ sudo systemctl disable xxnetwork-chain
After you have completed the maintenance …
On the node computer …
$ sudo ln -s /opt/xxnetwork/xxnetwork-cmix.service /etc/systemd/system
$ sudo ln -s /opt/xxnetwork/xxnetwork-chain.service /etc/systemd/system
$ sudo systemctl daemon-reexec
$ sudo systemctl start xxnetwork-chain
On the gateway computer …
$ sudo ln -s /opt/xxnetwork/xxnetwork-gateway.service /etc/systemd/system
$ sudo ln -s /opt/xxnetwork/xxnetwork-chain.service /etc/systemd/system
$ sudo systemctl daemon-reexec
$ sudo systemctl start xxnetwork-chain
Check the chain.log on both computers to see they have completed syncing. You will see Idle and Imported log messages such as …
2022-08-08 17:16:37 💤 Idle (37 peers), best: #3770905 (0x96a3…94d1), finalized #3770902 (0xd3a2…38e5), ⬇ 477.4kiB/s ⬆ 642.0kiB/s
2022-08-08 17:16:42 💤 Idle (37 peers), best: #3770905 (0x96a3…94d1), finalized #3770903 (0x8aa7…0ed0), ⬇ 243.3kiB/s ⬆ 247.7kiB/s
2022-08-08 17:16:42 ✨ Imported #3770906 (0x0bf6…4d67)
2022-08-08 17:16:42 ✨ Imported #3770906 (0x7540…62f7)
2022-08-08 17:16:47 💤 Idle (37 peers), best: #3770906 (0x0bf6…4d67), finalized #3770904 (0x2acb…d930), ⬇ 315.9kiB/s ⬆ 685.9kiB/s
Once both are synced …
On the node computer …
$ sudo systemctl start xxnetwork-cmix
On the gateway computer …
$ sudo systemctl start xxnetwork-gateway
To enable the services to start at boot run …
On the node computer …
$ sudo systemctl enable xxnetwork-cmix
$ sudo systemctl enable xxnetwork-chain
On the gateway computer …
$ sudo systemctl enable xxnetwork-gateway
$ sudo systemctl enable xxnetwork-chain
Finally, go to xx network Wallet > Staking > Account actions and press Validate
to the right of the stash account. Then wait to be elected.