Figure 53 Example multipath configuration

Why use multiple paths

With previous versions of Data Protector, a device could be accessed from only one client. To overcome this problem, several logical devices had to be configured for a physical device using a lock name. Thus, if you were using lock names for configuring access from different systems to a single physical device, you had to configure all devices on every system. For example, if there were 10 clients which were connected to a single device, you had to configure 10 devices with the same lock name. With this version of Data Protector, you can simplify the configuration by configuring a single multipath device for all paths.

Multipath devices increase system resilience. Data Protector will try to use the first defined path. If all paths on a client are inaccessible, Data Protector will try to use paths on the next client. Only when none of the listed paths is available, the session aborts.

Path selection

During a backup session, the device paths are selected in the order defined during the device configuration, except if a preferred client is selected in the backup specification. In this case, the preferred client is used first.

176

Media management and devices