{"id":851,"date":"2011-11-07T17:19:30","date_gmt":"2011-11-07T22:19:30","guid":{"rendered":"http:\/\/wildow.com\/?p=851"},"modified":"2011-11-07T17:19:30","modified_gmt":"2011-11-07T22:19:30","slug":"info-on-2008-backups-from-bradley-blog","status":"publish","type":"post","link":"https:\/\/wildow.com\/?p=851","title":{"rendered":"info on 2008 backups from Bradley blog"},"content":{"rendered":"

http:\/\/msmvps.com\/blogs\/bradley\/archive\/2011\/10\/04\/more-about-the-sbs-2011-standard-and-essentials-backup-engine.aspx<\/a><\/p>\n

I’m posting this as a FYI<\/p>\n

http:\/\/social.microsoft.com\/Forums\/en-US\/partnerwinserverebs\/thread\/0022ed92-b0a5-461b-82dc-f4a29d93550d<\/a><\/p>\n

From your description, I understand that:
\n
\nYou configured two 500GB external drivers for server backup. After 105
\ndays of daily backups, it now reports low space warning. You wonder how
\nthe backup space is automatically managed, and how to properly deal with
\nthe low space warning.<\/p>\n

If there is any misunderstanding, feel free to let me know.<\/p>\n

First, sorry for the delay due to weekend. I realize that you posted the
\nquestion on public SBS forum. Please kindly understand that the public
\nforums are NOT monitored by us. For your information, the partner forum
\nis labeled as (Partner) such as\u00a0*Windows Server (Partner) Forums*<\/strong>.<\/p>\n

Ira, it is actually frequently asked questions – how disk usage is
\nautomatically managed by Windows Server Backup? Why sometimes backup
\nwould fail with target out of disk space in spite of automatic disk
\nusage management feature in Windows Server Backup?<\/p>\n

The storage team has an official blog to address the inquiries:<\/p>\n

Windows Server Backup automatic disk usage management<\/p>\n

http:\/\/blogs.technet.com\/b\/filecab\/archive\/2011\/03\/14\/windows-server-backup-automatic-disk-usage-management.aspx<\/a><\/p>\n

The blog explicitly answers the following questions:<\/p>\n

Q1. What is Automatic disk usage management feature in Windows Server
\nBackup?<\/p>\n

Q2. How does the auto-delete functionality of Windows Server Backup works?<\/p>\n

Q3. What are the criteria on which this feature works?<\/p>\n

Q4. Why does backup fail with target out of disk space in spite of
\nautomatic disk usage management feature in Windows Server Backup?<\/p>\n

To summarize and address your questions:<\/p>\n

1. Windows Server backup (WSB) does automatically manage the disk usage.
\nIt can automatically reuse the space occupied by older backups when
\ncreating new backups.<\/p>\n

The Automatic Disk usage management feature comes into play when WSB
\ndetects that the backup target does not have enough space to accommodate
\nthe backup while backup is in progress. The way WSB creates space for
\nnew backup is by shrinking the storage space allocated for snapshots
\n(called diff area). As a result, one or more older snapshots (and hence
\nbackup versions corresponding to those snapshots) occupying the diff
\narea that got shrunk get deleted. Before shrinking diff area, WSB
\ndetermines whether shrinking the diff area can free up the requisite
\nspace so the backup can happen. If enough free space can get created,
\nWSB goes ahead with the shrinking and continues with the backup.*WSB
\nwill not shrink the diff area to less than 1\/8 of Target volume size as
\nwe do not want to lose all past backups just to accommodate this one.
\nThis is why sometimes backup fail with target out of disk space in spite
\nof automatic disk usage management feature in Windows Server Backup.*<\/p>\n

**<\/p>\n

Note: Space used by a System state backup is not automatically managed.
\nSee the section \u201c*How to Delete System State Backups*<\/strong>\u201d section of the
\nfollowing article for managing system state backups.<\/p>\n

Backup Version and Space Management in Windows Server Backup<\/p>\n

http:\/\/blogs.technet.com\/filecab\/archive\/2009\/06\/22\/backup-version-and-space-management-in-windows-server-backup.aspx<\/a><\/p>\n

For example, you can keep the latest N versions of system state backup
\non a backup storage location via command:<\/p>\n

*Wbadmin delete systemstatebackup -keepversions:N*<\/strong><\/p>\n

**<\/p>\n

2. As explain by the official blog, if you receive the low space
\nwarning, it means WSB has reached the state where the space required to
\ncomplete the new backup causes the snapshot storage space to become less
\nthan 1\/8 of the target size. In this case, you can manually delete the
\nold backups created by WSB per this article:<\/p>\n

http:\/\/blogs.technet.com\/filecab\/archive\/2009\/06\/22\/backup-version-and-space-management-in-windows-server-backup.aspx<\/a><\/p>\n

For example, you can delete the oldest shadow copy on the backup storage
\nlocation via command:<\/p>\n

Diskshadow.exe<\/p>\n

Delete shadows OLDEST \\\\?\\Volume{GUID}<\/p>\n

3. Only the number of System state backup can be configured via command
\n*Wbadmin delete systemstatebackup -keepversions:N*<\/strong><\/p>\n

**<\/p>\n

It is because the space of system state backup is not automatically
\nmanaged. For fully server backup or volume backup, WSB uses VSS to
\nmaintain backup version and automatically manage disk usage via the
\nAutomatic Disk usage management feature as explained before.<\/p>\n

Hope the information helps.<\/p>\n

————————————————————————
\nBest regards,<\/p>\n

*Tony Ma
\n*Partner Online Technical Community<\/p>\n","protected":false},"excerpt":{"rendered":"

http:\/\/msmvps.com\/blogs\/bradley\/archive\/2011\/10\/04\/more-about-the-sbs-2011-standard-and-essentials-backup-engine.aspx I’m posting this as a FYI http:\/\/social.microsoft.com\/Forums\/en-US\/partnerwinserverebs\/thread\/0022ed92-b0a5-461b-82dc-f4a29d93550d From your description, I understand that:<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-851","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/posts\/851","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wildow.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=851"}],"version-history":[{"count":1,"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/posts\/851\/revisions"}],"predecessor-version":[{"id":852,"href":"https:\/\/wildow.com\/index.php?rest_route=\/wp\/v2\/posts\/851\/revisions\/852"}],"wp:attachment":[{"href":"https:\/\/wildow.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=851"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wildow.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=851"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wildow.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=851"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}