High availability and disaster recovery options (On-premises)

IBM Power Virtual Server Private Cloud: On-premises

For the pod software, IBM® Power® Virtual Server removes all single points of failure by implementing redundancy as follows:

• Redundancy in power supplies to the servers that are connected to different power sources.
• Redundancy in network adapters that are connected to redundant network switches.
• Redundancy in Fibre Channel adapters that are connected to redundant storage area network (SAN) fabrics.
• A dual-VIOS setup with redundant subcomponents for each Virtual I/O Server (VIOS).
• A dual-HMC setup is provided with medium size pod. However, a small pod configuration has only a single HMC. For small pods, the standby system is shared between the managing and managed nodes.
• Dual storage systems that allow host-based mirroring of customer data.

By using the remote restart function, the Power Virtual Server restarts the virtual server instances on a different host system if a hardware failure occurs. This process provides basic High Availability (HA) capabilities against power failure. However, the remote restart function might not be helpful if a storage hardware fails. For advanced high-availability functions, you can implement HA clusters and HA services such as PowerHA SystemMirror, on the virtual server instances. For HA clusters, you must use server placement groups with anti-affinity policy to enable the functions of the following items:

• All virtual machines run on different systems.
• You have disks from different controllers.
• You can create mirror volume groups.

For client-managed applications, you must implement a high-availability strategy. For example, you can use solutions such as Red Hat Enterprise Linux High Availability or SUSE Linux Enterprise High Availability.