User manual APPLE XSAN 2 ADMINISTRATORS GUIDE

[. . . ] All rights reserved. Under the copyright laws, this manual may not be copied, in whole or in part, without the written consent of Apple. Use of the "keyboard" Apple logo (Option-Shift-K) for commercial purposes without the prior written consent of Apple may constitute trademark infringement and unfair competition in violation of federal and state laws. Every effort has been made to ensure that the information in this manual is accurate. Apple 1 Infinite Loop Cupertino, CA 95014-2084 408-996-1010 www. apple. com Apple, the Apple logo, Mac, Mac OS, Macintosh, the Mac logo, Tiger, Xsan, and Xserve are trademarks of Apple Inc. , registered in the U. S. [. . . ] 3 In the Configure Volume Affinities pane (Configure Volume Storage if you chose the custom volume type), drag LUNs to affinity tags (or storage pools). 4 On the Volume Failover Priority pane, drag the controller that you want to host the volume whenever possible to the top of the list. For information on advanced settings, see "Changing Advanced Volume Settings" on page 61 or "Changing Storage Pool Settings" on page 65. When you're finished, the volume is automatically mounted on all SAN clients. From the Command Line You can also add a volume by setting up a configuration file. For more information, see the cvfs_config man page or "Xsan Configuration Files" on page 131. 58 Chapter 4 Managing SAN Storage Setting Up a Folder Affinity Every storage pool in a volume has an affinity tag. You can use the tag to be sure that files in a folder are stored on a particular storage pool. Files folders without affinities are stored in the next available storage pool according to the volume's allocation strategy. You might have some storage pools that are larger, faster, or better protected than others. Using affinities, you can make sure that an application or task that needs speed or extra protection stores its files on a suitable storage pool. Using Xsan Admin, you can choose an affinity for an existing folder or create a new folder with an affinity. Action pop-up menu To assign an affinity tag to a folder: 1 In Xsan Admin, select File Management in the SAN Assets list. 2 Select the folder in the columns that list the volume's contents, choose Set Affinity from the Action (gear) pop-up menu, and choose an affinity tag. If the folder doesn't already exist, you can choose New Folder from the Action (gear) pop-up menu, type a folder name, and choose an affinity tag. From the Command Line You can also assign an affinity to a folder using the cvmkdir command in Terminal. For more information, see the cvmkdir man page. Chapter 4 Managing SAN Storage 59 Changing a Folder's Storage Pool Affinity You can use Xsan Admin to change a folder's affinity so all new files placed in the folder are stored on a new storage pool. To change a folder affinity: 1 In Xsan Admin, select File Management in the SAN Assets list. 2 Select the folder, choose Set Affinity from the Action (gear) pop-up menu, and then choose the new affinity tag. Files already in the folder are not automatically moved to the new storage pool. To move the files that were in the folder to a storage pool with the new affinity tag, use the snfsdefrag command in Terminal. For information and an example, see the snfsdefrag man page. Removing an Affinity You can undo a folder's affinity for a storage pool by choosing None for the folder affinity. To remove the affinity tag from a folder: 1 In Xsan Admin, select File Management in the SAN Assets list. 2 Select the folder, choose Set Affinity from the Action (gear) pop-up menu, and choose None for the affinity tag. 60 Chapter 4 Managing SAN Storage Changing Advanced Volume Settings If your SAN volume has special configuration requirements, you can change the standard volume settings when you create a volume. [. . . ] RAID 1 A RAID scheme that creates a pair of mirrored drives with identical copies of the same data. RAID 3 A RAID scheme that stripes data across two or more drives and stores parity data on a dedicated drive. In the event of a disk failure, the redundant parity bits can be used to reconstruct data on any drive. RAID 5 A RAID scheme that distributes both data and parity information across an array of drives one block at a time, with each drive operating independently. [. . . ]