Specifying the Mirror Path
When you mirror virtual volumes, SANsymphony software balances the mappings over available paths. You can specify the mirror paths to use for each storage server by using the Mirror Path feature. This feature allows you to limit the number of paths to use by selecting individual paths from the list of all available paths.
IMPORTANT: Mirror path configurations, such as using specific mirror paths or redundant mirror paths, must be configured prior to creating a mirror. After a mirror configuration exists for a virtual volume, mirror path settings cannot be changed.
Additionally, if there are multiple paths to a target, to provide mirror path failover, enable the Redundant Mirror Paths feature. In order to use the Redundant Mirror Paths feature, LUN distribution must be enabled for the specified paths and have the required paths selected as mirror paths. (LUN distribution is enabled by default.)
CAUTION: Redundant mirror paths are not supported with Dual Path (DP) configurations or iSCSI. If you have a DP configuration, refer to About Dual Path for special considerations.
The Mirror Paths feature is accessible from the context menu by clicking on a storage server in the Channels, Virtual Volumes, AIM, and Snapshot tabs in SANmanager, as well as the Configurations Preferences option on the Preferences menu.
To specify the mirror path:
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Select a storage server in the left pane, and choose Mirror Paths from the context menu.
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Select the appropriate Server Pair from the menu.
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To configure redundant mirror paths, select the Redundant Mirror Paths check box. (Storage servers must have at least two independent initiator and target paths in each required direction added to the Mirror Paths area of this dialog box in step 4.)
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To add specific mirror paths, select one or more paths from the Available Paths list box and click Add. Mirror mappings will be balanced over all of the selected paths.
For redundant mirror paths, a total of four paths are required; two separate paths from server A to server B, and two separate paths from server B to server A.
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To remove paths, select the paths in the Mirror Paths list, and click Remove.
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After completing your selections, click OK.
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Apply the configuration.