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==NAME==
See {{man|8|amfetchdump}}.
     
'''amfetchdump''' - extract backup images from multiple Amanda tapes.
 
==SYNOPSIS==
amfetchdump [-pcClawns] [-d device] [-o directory] [-i logfile] [-b blocksize] config hostname [disk [date [level [hostname [...]]]]]
 
==DESCRIPTION==
Amfetchdump  pulls  one  or  more matching dumps from tape or from the holding disk, handling the reassembly of multi-tape split  dump  files as well as any tape autochanger operations.
 
It  will  automatically  use  the  logs created by [[amdump]](8) to locate available dumps on tape, in the same way  that  the  find  feature  of [[amadmin]](8)  lists  available  dumps. If these logs are unavailable, it can search tape-by-tape to find what it needs, and  can  generate  new logs to serve as an emergency tape inventory.
 
The  hostname,  diskname,  datestamp,  and level dump pattern-matching works as in [[amrestore]](8), with the added requirement that at minimum a hostname must be specified when not in inventory mode.
 
Unless -p is used, backup images are extracted to files in the current directory named:
 
      hostname.diskname.datestamp.dumplevel
 
==OPTIONS==
 
;-p : Pipe exactly one complete dump file to stdout, instead of writing the file to disk. This will restore only the first matching dumpfile (where "first" is determined by the  dump  log  search facility).
 
;-d device : Restore from this tape device instead of the default.
 
;-o directory : Output restored files to this directory, instead of to the current working directory.
 
;-c : Compress output, fastest method available.
 
;-C : Compress output, smallest file size method available.
 
;-l : Leave dumps in the compressed/uncompressed state in which  they were  found on tape. By default, amfetchdump will automatically uncompress when restoring.
 
;-a : Assume that all tapes are already available, via  tape  changer or  otherwise, instead of prompting the operator to ensure that all tapes are loaded.
 
;-i filename : Generate an inventory of all  dumps  "seen"  on  the  tapes  we search, for later use as a log.
 
;-w : Wait to put split dumps together until all chunks have been restored. Normally, amfetchdump will attempt to read pieces of  a
split  file  from  tape  in order, so that it can assemble them simply by appending each file to the first.  This  option  disables            the  appending behavior, and instead restores each piece as an individual file and reassembles them only after all have              been restored.             
 
Note that this requires at least double the size of your dump in free disk space, in order to build the final assembled dumpfile.
This  behavior  is  implicitly  invoked  in circumstances where knowing the location of all dumps on tape  in  advance  is  not possible, such as when you are restoring without log files.
 
; -n : Do  not  reassemble  split dump files at all, just restore each piece as an individual file.
 
; -s : Do not fast-forward straight to needed files on tape. This will slow  down most restores substantially. Only use this option if your tape drive does not properly support the fast-forward  operation.
 
;-b blocksize : Force  a  particular  block  size when reading from tapes. This value will usually be autodetected,  and  should  not  normally need to be set.
 
==EXAMPLES==
 
All the examples here assume your configuration is called SetA.
 
Here’s  a  simple case, restoring all known dumps of the host vanya to the current working directory.
 
      $ amfetchdump SetA vanya
 
A more likely scenario involves restoring a  particular  dump  from  a  particular  date. We’ll pipe this one to GNU tar as well, to automatically extract the dump.
 
      $ amfetchdump -p SetA vanya /home 20051020 | gtar -xvpf -
 
In a situation where all of our dump logs  have  been  wiped  out,  we could also use amfetchdump to inventory our tapes and recreate an imitation of those logs, which we’ll send to stdout for casual perusal.
 
      $ amfetchdump -i - SetA
 
Note that you can specify a restore while in inventory mode,  and  amfetchdump  will  continue searching for more dumps from this host even after successfully restoring a dump, inventorying all  the  while.  If your  backup searcher has been trashed, this is a handy way to recover what you have.
 
      $ amfetchdump -i /var/amanda/log SetA backupserver
 
==CAVEATS==
 
Amfetchdump is dependent  on  accessing  your  server’s  config,  tape changer,  and  (normally) dump logs. As such, it’s not necessarily the most useful tool when those have all been wiped out and you desperately  need  to pull things from your tape. Pains have been taken to make it as capable as possible, but  for  seriously  minimialist  restores, look to [[amrestore]](8) or [[amdd]](8) instead.
 
==AUTHOR==
     
John Stange, National Academies Press
 
Ian Turner, Zmanda, Inc.: XML-conversion
 
==SEE ALSO==
 
[[amanda]](8), [[amadmin]](8), [[amrestore]](8), tar(1)  restore(8)

Latest revision as of 20:33, 30 June 2008