View source for Source:Administering Si3 NG Deduplication Store/Repairing corrupted Si3 NG data store/en

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You can repair the Si3 NG store when pages or objects get corrupted. 

<ol><li>First determine the scope of corruption:
<ul><li>To get the list of corrupted objects use:
<pre>sm_dedup_interface -d <datastore> corruptedobjects</pre></li>
<li>To get the list of corrupted pages use:
<pre>sm_dedup_interface -d <datastore> corruptedpages</pre></li></ul></li>
<li>Use the following command to replace the page in <tt>/pages</tt> directory with an older version from <tt>/pages-trash</tt> directory:
<pre>sm_dedup_interface -d <datastore> repair pages</pre>
The pages in trash contain all chunks deleted on previous GC. The oldest version of a page takes priority.</li>
<li>Use the following command to search for and recover the missing chunks in <tt>/pages-trash</tt> directory:
<pre>sm_dedup_interface -d <datastore> repair start</pre>
During the repair process a new page is created, which contains all chunks from the current page (page affected by 'missing chunks' issue) and all chunks found in the trash.</li></ol>

===Cleanup of unrecoverable Si3 NG store===

{{warning|You should use the commands described in this section only in case the corrupted store cannot be recovered.}}

When corruptions in the Si3 NG store persist, the initial page version has already been purged from trash or there were fatal errors during backup or restore. In this case broken pages or missing chunks cannot be recovered.

Cleanup can be performed by deleting unrecoverable objects manually or by using the automatic cleanup function. 

;Deleting objects

When there are only a few unrecoverable objects, delete each object with the following commands: 
 sm_dedup_interface -d <datastore> delete corruted_object_id_1
 
 ...
 
 sm_dedup_interface -d <datastore> delete corruted_object_id_Nth

In case of many corruptions you can delete all corrupted objects using the following command: 
 sm_dedup_interface -d <datastore> fsck purge

;Garbage collection
When you have deleted all unrecoverable objects, run ''garbage collection'' (<tt>gc</tt>):
 sm_dedup_interface -d <datastore> gc start

;Automatic cleanup function
To start an automatic cleanup function, use the following command: 
 sm_dedup_interface ... fsck purge auto
The automatic cleanup function runs the following sequence of commands: <tt>PCCK start -> OCCK start -> Delete all corrupted objects -> GC start</tt>.

===Logging===

The logging function uses a relatively powerful ''logback'' library. For more information, see  [http://logback.qos.ch/ Logback Project]. Note that this information is intended for advanced users only.

;Logging info
*<tt>gv_rw_ini:sm_sds.xml (/var/opt/sesam/var/ini/sm_sds.xml)</tt>
*<tt>/var/opt/sesam/var/log/sms</tt> contains two log files:
**<tt>sm_dedup_server_info-<drive>.log</tt>: Log level INFO and higher.
**<tt>sm_dedup_server-<drive>.log</tt>: Log level DEBUG and higher. This file can become quite large.
**<tt>sm_dedup_gc-<drive>.log</tt>: garbage collection log.
**<tt>sm_dedup_fsck-<drive>.log</tt>: file system check log.
*Auto rotation if the log file size reaches 100 MB.

===Files and directories===

;Objects
For every SEP sesam saveset, three objects (files) are stored in the Si3 NG store:
*<tt><ssid>.data</tt>
*<tt><ssid>.info</tt>
*<tt><ssid>.info2</tt>

The <tt>.data</tt> and <tt>.info</tt> files are identical to those of a normal data store. The <tt>.info2</tt> file is required for the data to be appended to a Si3 object. All database information that is not available before a backup is completed is written to this file.

;Directories