(C)SEP AG

Copyright 1999-2011 by SEP AG. All Rights reserved.

Any form of reproduction of the contents or parts of this manual is allowed only with the express written permission from SEP AG. When compiling and designing user documentation SEP AG uses great diligence and attempts to deliver accurate and correct information. However, SEP AG cannot issue a guarantee for the contents of this manual.

Introduction

A media pool is referenced to one point on a storage system. In consequence in case of growing memory requirements the storage system just reaches its capacity and cannot be extended anymore. It's not possible to add additional space of further storage devices to the same media pool with the former media pool configuration dialog. From SEP sesam version 3.4 upward therefore an additional option is introduced - the storage pool.

Description

Storage pools expands media pools to an additonal level. This means that media pools can consist of 1-N storage pools. This ensures a dynamical extension of the media pool. If necessary a further storage pool is just assigned to the media pool.

On the left hand side of figure above the classical usage of media pools is shown. The media pool is referenced to /sesamdisk on the filesystem. Beneath this point SEP sesam creates the virtual media. In contrast the right hand side illustrates a media pool by using storage pools SP01, SP02 and SP03. This example shows a media pool consisting of 3 storage pools which reference to a disk storage on filesystem mounted via NFS and/or external storage media. E.g. if the NFS share of SP02 is mounted to /sesam_nfs/sp02 in the local filesystem of the SEP sesam server you can register media to the storage pool SP02 and the corresponding subdirectories of every media will be created under this location.

Configuration

Example 1 will show the configuration of a media pool with using storage pools with static access. That means the storage pool locations are existing permanently in the locale filesystem.

Data for example 1:

• Media pool definition
  • Name of the media pool = SPstatic
  • Media pool size = 1 GB
  • size of a single media = 100 MB
• Storage pool definition
  • Name of storage pool 1 = SPstat1
  • Storage pool 1 size = 300 MB
  • Storage pool 1 location = /srv/SPstatic/SPstat1
  • Name of storage pool 2 = SPstat2
  • Storage pool 2 size = 600 MB
  • Storage pool 2 location = /srv/SPstatic/SPstat2

Example 2 will show the configuration of a media pool with using storage pools by using the advanced feature Dynamic Access. This feature provides a possibility to mount a storage pool just in time for use. This feature only works if the operating system supports this functionality. To demonstrate how it works we use loop devices in this example.

To reprocude this example:

1. Create to files with 500 MB size each and format them with ext3
   • dd if=/dev/zero of=/srv/storage/loopdev01 bs=500M count=1
   • mkfs.ext3 loopdev01
   • dd if=/dev/zero of=/srv/storage/loopdev02 bs=500M count=1
   • mkfs.ext3 loopdev02

Data for example 2:

• Media pool definition
  • Name of the Media Pool = SPtest
  • Media Pool size = 1 GB
  • size of a single media = 100 MB
• Storage pool definition
  • Name of Storage Pool 1 = SP01
  • Storage pool 1 size = 500 MB
  • Storage pool 1 location = /srv/storage/SP01
  • Name of storage pool 2 = SP02
  • Storage pool 2 size = 500 MB
  • Storage pool 2 location = /srv/storage/SP02

Create a Media Pool

The creation of a media pool is in both examples the same way. If you create a new media pool the storage pool option will not be displayed.

Modify the Media Pool

Edit the media pool configration to switch on the storage pool option.

• Activate the option use Storage Pools. A additional dialog page and a additional button appear.
• Press the button Storage Pools to create new or edit existing storage pools.

Example 1 with static Storage Pools

Create Storage Pools

• Create SPstat1 by clicking the button New, after the input finish by clickingApply

• Create SPstat2 by clicking the button Copy, change the values as requested, then click Apply

• After creating of all necessary storage pools close the dialog by clicking OK

Assign the Storage Pools to the appropriate Media Pool

Example 2 with dynamic Storage Pools

Creating media pools and switching on storage pools is descibed above. After clicking Storage Pools you can create new, modify and/or delete existing storage pools.

Create Storage Pools

• Name Name of storage pool.
• Path Shows the location on the file system where the virtual media of that pool are created. NFS shares or external volumes which are dynamically mounted on the system can be used as well.
• Capacity The maximum size in MB which may be allocated on the storage device by that pool.
• Description optional

• Command for Loading (optional) Command which is used by the operating system to mount a dynamic storage device. A external script can be used as well. This script gets the device path as its first parameter.
• Command for Unloading (optional) Command which is used by the operating system to unmount a dynamic storage device. A external script can be used as well. This script gets the device path as its first parameter.
• Device Path Specifies the device path to the storage device.

The example shows a loop mounted volume which is dynamically mounted and unmounted in the system depending on how SEP sesam handles the media pool above. This means by every action a medium of that storage pool is used the device file is mounted on the file system and after use will be unmounted.

Assign the Storage Pools to the appropriate Media Pool

You can select the desired storage pools from the pick list and move them to the picked list. With the priority value you can control in what order the storage pools will be used on backup.

Register media to the Media Pool

For every storage pool in the media pool you have to register the media in a separate step by archive adjustment. Select the loader view in the SEP sesam GUI (Components/ Loaders in the object panel on the left) and start the achive adjustment by clicking Archive Adjustment.

The description relates to the values of example 1.

• Select and enter the following values for the fields:
  • Media Pool = SPstatic
  • Storage Pool = SPstat1 --> is the first Storage Pool
  • First slot leave 0 (zero). The slot countalways begins at zero, the automatic numbers for media begins at 1 (e.g. SPstatic00001).
  • Last slot = 2 - because 3 new media should be created. If no media exist for the media pool the default value is -1. Calculate from last slot (2) of a existing media from storage pool 1 (SPstat1)

Initiate the archive adjustment by clicking the Start button and wait until the message of success ('Archive adjusting completed successfully'= displayed in the Current messages window. Then start the archive adjustment for the next storage pool.

• Call the function archive adjustment again for creating new media in storage pool SPstat2. Select...
  • Media Pool = SPstatic
  • Storage Pool = SPstat2 --> is the next storage pool
  • First slot leave 0 (zero)
  • Last slot = 8 (calculate from last slot (2) of a existing media from storage pool 1 (SPstat1) added with 6 new media in storage pool 2 (SPstat2) results in 8)