Storage Cluster Maintenance Operations Overview
Maintaining the Cisco HyperFlex (HX) Data Platform storage cluster tasks affect both hardware and software components of the storage cluster. Storage cluster maintenance operations include adding or removing nodes and disks, and network maintenance.
Some steps in maintenance tasks are performed from the storage controller VM of a node in the storage cluster. Some commands issued on a storage controller VM affect all the nodes in the storage cluster.
Three node storage clusters. Contact Technical Assistance Center (TAC) for any task that requires removing or shutting down a node in a three node cluster. With any 3 node storage cluster, if one node fails or is removed, the cluster remains in an unhealthy state until a third node is added and joins the storage cluster.
Upgrading from vSphere 5.5 to 6.0. Before you upgrade either your ESX server or your vCenter server from 5.5 to 6.0, contact Technical Assistance Center (TAC).
Adding nodes. Nodes are added to the storage cluster through the Expand Cluster feature of the Cisco HX Data Platform Installer. All new nodes must meet the same system requirements as when you installed the Cisco HX Data Platform and created the initial storage cluster. For a complete list of requirements and steps for using the Expand Cluster feature, see the appropriate Cisco HX Data Platform Install Guide.
Online vs Offline Maintenance
Depending upon the task, the storage cluster might need to be either online or offline. Typically maintenance tasks require that all nodes in the storage cluster are online.
When storage cluster maintenance is performed in an offline mode, this means the Cisco HX Data Platform is offline, however
the storage controller VMs are up and Cisco HX Data Platform management is viewable through the
stcli command line, HX Connect, and HX Data Platform Plug-in. The vSphere Web Client can report on the storage I/O layer. The
stcli cluster info command returns that the overall storage cluster status is
Before you perform maintenance on the storage cluster, ensure the following.
Identify the maintenance task to be performed.
All maintenance operations such as remove/replace resources are done during maintenance windows when the load on the system is low.
The storage cluster is healthy and operational before the maintenance tasks.
Identify disks using the HX Connect or HX Data Platform Plug-in Beacon options.
The HX Beacon option is not available for housekeeping 120GB SSDs. Physically check the server for the location of the housekeeping SSD.
Check the list of maintenance tasks that cannot be performed in parallel. See Serial vs. Parallel Operations for more information on these tasks.. You can perform only some tasks serially to each other.
Ensure that SSH is enabled on all the ESX hosts.
Put the ESX host into HX Maintenance Mode prior to performing a maintenance task on the host. The HX maintenance mode performs additional storage cluster specific steps compared to the vSphere provided ESX maintenance mode.
Post Maintenance Tasks
After the maintenance task is completed, the nodes need to exit Cisco HX Maintenance Mode and the storage cluster needs to be restarted. In addition, some changes to the Cisco HX storage cluster require additional post maintenance tasks. For example, if you change the vNICs or vHBAs, the PCI Passthrough needs to be reconfigured. For more information describing how to reconfigure the PCI Passthrough, see Configure PCI Passthrough After Changing vNIC or vHBAs.
Ensure the following:
The ESX host is exited from Cisco HX maintenance mode after performing maintenance tasks on the host.
The storage cluster is healthy and operational after any remove or replace tasks are completed.
If vNICs or vHBAs have been added, removed, or replace on any ESX host in the Cisco HX storage cluster, reconfigure the PCI Passthrough.