Unix dump
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<code><p>mkdir extracted</p></code> | <code><p>mkdir extracted</p></code> | ||
<code><p>cd extracted</p></code> | <code><p>cd extracted</p></code> | ||
| − | <li><p>Run <code>restore</code> in interactive mode on the dump file you want to extract | + | <li><p>Run <code>restore</code> in interactive mode on the dump file you want to extract</p> |
<code>sudo restore -if ../../tapes-DDS/1/file000002.dd</code></li> | <code>sudo restore -if ../../tapes-DDS/1/file000002.dd</code></li> | ||
<li><p>Inspect the contents of the dump file:</p> | <li><p>Inspect the contents of the dump file:</p> | ||
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<li><p>Now enter <code>1</code>. Response:</p> | <li><p>Now enter <code>1</code>. Response:</p> | ||
<pre>set owner/mode for '.'? [yn]</pre></li> | <pre>set owner/mode for '.'? [yn]</pre></li> | ||
| − | <li><p>Enter <code>n</code | + | <li><p>Enter <code>n</code></p></li> |
<li><p>When the extraction is finished, exit the interactive restore session:</p> | <li><p>When the extraction is finished, exit the interactive restore session:</p> | ||
<code>restore > q</code></li></ol> | <code>restore > q</code></li></ol> | ||
Latest revision as of 17:20, 29 January 2019
dump is an archive format that is written by Unix dump, which is a backup program that was popular in the '90s (reference?). Dump files were often written to tape. Dump files can be read using the restore tool. It appears that no specifications exist.
Contents |
[edit] Variants
There are a number of variants to the Unix dump format.
The file(1) magic definition of the format makes a distiction between 'old' and 'new' filesystem variants. Each of these can be big-endian or little endian. In addition a 16-bit subtype of the 'old' variant exists. Finally there is also a ufs2 variant (which again can be big-endian or little endian). In total this results in 7 variants of the format. According to the restore documentation, the dump file format changed in version 4.4 (of the dump tool?).
[edit] Software
[edit] Documentation
[edit] Sample files
- Unix dump format - includes some minimal sample files, created for testing magic patterns
[edit] Restoring the contents of a dump file
To restore the contents of a dump file on a Unix system, first the install the "restore" tool. On Debian-based systems:
sudo apt install dump
Then go through the following steps:
Create an empty directory, and go to that directory in the command terminal:
mkdir extracted
cd extracted
Run
restorein interactive mode on the dump file you want to extractsudo restore -if ../../tapes-DDS/1/file000002.ddInspect the contents of the dump file:
restore > lsResult:
5bin/ diag/ kvm/ mdec share/ ucbinclude 5include/ dict/ lddrv/ net spool ucblib 5lib/ etc/ lib/ nserve src xpg2bin/ adm export/ local old/ stand xpg2include/ bin/ games/ local-/ openwin/ sys xpg2lib/ boot hosts/ lost+found/ pub tmp demo/ include/ man sccs/ ucb/
Use the
addcommand to add directories that are to be extracted to the directory list. To extract everything:restore > add .Run the
extractcommand:restore > extractThis results in the following prompt:
You have not read any volumes yet. Unless you know which volume your file(s) are on you should start with the last volume and work towards the first. Specify next volume # (none if no more volumes):
Now enter
1. Response:set owner/mode for '.'? [yn]
Enter
nWhen the extraction is finished, exit the interactive restore session:
restore > q
[edit] References
- Wikipedia:Dump_(program)
- Is dump really deprecated?
- Using Dump for Linux/Unix data backup
- Restore Linux Commands
- How to Restore UFS Files Interactively
- file(1) magic for dump file format (also includes patterns for extraction of header fields)
