Veritas Access Appliance Administrator's Guide

To create a shared cache object for Access Appliance instant rollbacks

• To create a shared cache object for Access Appliance instant rollbacks, enter the following:

  Storage> rollback cache create cache_name [cache_size] [pool]

  cache_name	Indicates the name of the cache object you want to create.
  cache_size	Indicates the cache size for the cache object. Cache size can be specified in any units, such as M, G, or T. The size of the shared cache object should be sufficient to record changes to the file system during intervals between instant rollback refreshes. By default, the size of the cache object for an instant rollback is 20% of the total size of the parent file system. The size of the cache object is dependent on your environment.
  pool	Indicates the pool for storing the cache object. For better performance, the pool used for the space-optimized rollback should be different from the pool used by the file system.

To convert an existing file system into a cache object

1. Select or create a file system with the layout that you want to use for the cache object. In this way, you can create cache objects with any kind of file system type. If you use an existing file system, the data on the file system is lost when you convert it to a cache object.

   The following example shows how to create a file system with a file system type of striped:

   Storage> fs create striped cobj1 100m 2 pool0
   100% [#] Creating striped filesystem

2. Run the Storage> rollback cache create command without the cache_size and pool parameters:

   Storage> rollback cache create cache_name

   cache_name is the name of the file system from step 1 that you want to convert.

   A confirmation message in the Access Appliance CLI asks if you want to convert the specified file system to a cache object.

   For example, to convert the striped file system cobj1 to a cache object:

   Storage> rollback cache create cobj1
   ACCESS rollback WARNING V-288-0 Filesystem cobj1 will be converted to 
   cache object. 
   All data on Filesystem cobj1 will be lost
   ACCESS rollback WARNING V-288-0 Are you sure you want to convert cobj1 
   to a cache object? (yes/no)
   yes
   100% [#]

3. Verify that the new cache object exists:

   Storage> rollback cache list
   CACHE NAME    TOTAL(Mb)   USED(Mb) (%)   AVAIL(Mb) (%)  SDCNT
   cache1        15          15 (100)       0  (0)         2
   cobj1         100         4  (4)         96 (96)        0