10400455-002
©2008-14 Overland Storage, Inc.
215
SnapScale/RAINcloudOS 4.1 Administrator’s Guide
8 - Maintenance
Online/Rolling Updates Notes
The Online/Rolling Update option allows you to update the RAINcloudOS while leaving the
SnapScale cluster online and active. Each node is upgraded and rebooted one at a time, and as
a result, degrades the peer sets with members in that node during that process. After
upgrade/reboot, each node rejoins the cluster and all peer sets are fully rebuilt before the
rolling update proceeds to the next node. This repeats until all nodes have been upgraded (or
a failure is encountered).
To prevent problems and data loss, consider the following caveats:
•
If upload fails on one or more nodes, the upgrade will abort with an error and list the
nodes that had problems.In such a case, an Offline Update is required.
•
If you abort the Online/Rolling Update during the update process, the process stops
where it is resulting in a mixed-OS state which needs to be resolved immediately. Then
proceed using the Offline Update to complete the update of the cluster.
•
All nodes must be in a healthy state to perform Online/Rolling Updates (
Storage >
Nodes
). If they are not healthy, they need to have any issues addressed before
continuing:
•
Using Offline Updates, update the OS on nodes with different OS versions. After
updating, verify the node is now healthy, resolving any remaining issues.
•
Replace any unhealthy drives on nodes.
•
Replace any unhealthy nodes.