Unattended-upgrades and failover
I have a pair of EC2 instances which are configured with
AWS healthchecks and failover DNS, i.e. if one goes down
the DNS will send requests only to the other.
I would like to configure unattended-upgrades to that:
1. The two instances don't both attempt to upgrade at
the same time. I guess that's just a matter of tweaking
the cron entry.
2. If one instance is down, i.e. its AWS healthcheck is
failing, either because an unattended-upgrade has failed
or for some other reason, I don't want the other instance
to try to install any upgrades.
I can provide a script that checks the healthcheck status
using the AWS API.
Of course it's not especially difficult to write a wrapper
script for unattended-upgrades, but I thought I would ask
here in case anyone has tried to do anything similar.