KVM Rolling Maintenance | CloudStack Feature First Look
In a typical scenario prior to this feature, the administrator had to automate the process of setting hosts in maintenance before upgrading, usually using external automation tools. This feature allows administrators to perform the entire process within CloudStack, providing a flexible framework that allows defining custom scripts to execute on each host. CloudStack executes these scripts within the context of 4 stages: Pre-flight script runs on hosts before commencing the rolling maintenance. If pre-flight check scripts return an error from any host, then rolling maintenance will be cancelled with no actions taken, and an error returned. If there are no pre-flight […]