If you have slices that are affected, you will receive notification of the specific slices impacted, steps required, and relevant dates. The purpose of this page is to provide more detailed information and answer common questions.
What does this mean for me in one sentence?
Some slices need to be migrated so the underlying hosts (the physical servers that slices run on) can be updated and those migrations require a slice reboot.
Do I need to do anything?
You only need to take action if you have slices that are impacted (you will receive an email maintenance notification if you do) and wish to control when certain slices are migrated. If you wish to control your migrations, please see below for details on how to perform an automated self-migration. If you do not self-migrate, Rackspace will automatically migrate slices on your behalf.
Why are migrations required?
Maintenance and upgrades are routinely performed on Slicehost systems, the majority of which are done transparently and with no impact to individual slices. In some cases however, the host itself needs to be updated which renders it unable to run slices for the duration of the update. Since the downtime associated with a slice migration is less than that of a host update, migrating slices is the least impactful way of deploying the update.
Can I postpone or opt out?
Managed migrations cannot be postponed nor can affected slices be opted out. Automated self-migrations are provided to allow you to control individual slice migrations at your convenience, within the provided self-migration window.
Will migrations change my IP addresses?
No, all IP addresses associated with your slices will remain the same.
How do I perform an automated self-migration?
Simply use the SliceManager or Slicehost API to perform a soft reboot of the affected slice. The first time this is done after you are notified of a need to migrate, your slice will be migrated, then rebooted, instead of just rebooted. Please note that there will be a delay while your slice data is copied to the new host before the reboot occurs. Once migrated, any subsequent reboots of that slice will result in a traditional reboot.
Please note that rebooting from within your slice (e.g. via SSH or the console) will NOT initiate an automated self-migration.
How is a migration performed?
While the slice is still running, a disk snapshot is transparently taken and the data copied to another host. During this time, the slice is still up and operational and any writes to disk are being tracked. After the base snapshot data has been fully copied to the new host, the slice is gracefully shut down, changes that have occurred since the beginning of the snapshot are synchronized, and the slice is booted. Albeit disruptive, the migration process minimizes downtime to a reboot plus the time it takes to copy over delta snapshot changes.
How long will my slice be down during a migration?
Actual slice downtime should not be much longer than a reboot, however, the length of time will vary based on the amount of data that changes during the snapshot process. If you are performing an automated self-migration, it is recommended that you minimize writes to disk (e.g. stop applications, shutdown databases, etc.) as much as possible before starting the migration.
Will a migration affect the configuration of my slice?
Migrated slices will remain in the same datacenter and will retain the same IP addresses, applications and data, slice IDs, etc.
How do I know when a slice has been successfully migrated?
If you are performing an automated self-migration, after initiating a reboot, the slice “status” field in the SliceManager and Slicehost API will transition from “Queued for move” to “Preparing for move” to “Moving” and back to “Active” in lieu of the traditional reboot status changes. This will allow you to monitor the migration progress. Once your slice has transitioned through these statuses and has returned to “Active”, the migration is complete and your slice should be back online. For both self and managed migrations, you will also receive email confirmation for each slice that is successfully migrated. Once you have confirmation that a migration is complete, please take a moment to verify proper functioning of your slice and applications. If you have any questions or problems during or after a migration, please contact our support team immediately so we can investigate.
What about my other slices not listed in the maintenance notification?
Existing slices not listed in your maintenance notification as well as any new slices you launch do not require a migration.
What happens if I don’t self-migrate?
You will be given a period of time to self-migrate which will be clearly indicated in your notification of the need to migrate affected slices. Once the automated self-migration window passes, managed migrations will begin being scheduled for any slices that have not been self-migrated. You will be notified at least 24 hours in advance of any managed migrations and will be provided a specific time window in which the migration will occur. Please note that managed migrations may be spread out over a number of weeks and may also result in migrations occurring at inconvenient times or multiple of your slices being migrated at the same time. As such, please be sure to perform automated self-migrations for any slices where this may be problematic.
Will migrations be required again in the future?
While we always seek to perform non-disruptive maintenance and upgrades of underlying systems, it may be necessary in the future for various slices to be migrated or rebooted.