In enterprise environments where uptime and performance are critical, ensuring continuous and efficient access to storage is paramount. Multipathing is a technique used to provide multiple physical paths between the host and the storage devices. XenServer manages these multiple I/O paths, enabling both failover and load balancing capabilities. This not only enhances redundancy—ensuring that data traffic can seamlessly switch to another path in case of a failure—but also improves overall performance by distributing the I/O load across multiple paths.

This article provides information on using the multipath tools in XenServer to query the multipath status of your storage.

Multipath support in XenServer is based on the device-mapper multipathd components. The Storage Manager API handles activating and deactivating multipath nodes automatically. Unlike the standard dm-multipath tools in Linux, device mapper nodes are not automatically created for all LUNs on the system. Device mapper nodes are only provisioned when LUNs are actively used by the storage management layer. Therefore, it is unnecessary to use any of the dm-multipath CLI tools to query or refresh DM table nodes in XenServer.

If it is necessary to query the status of device-mapper tables manually, or list active device mapper multipath nodes on the system, use the mpathutil utility:

mpathutil list
mpathutil status