On Fri, 2 Mar 2007, Bill Moran wrote: > That "400G with compression" is just an average. There's no guarantee > that you'll get 2x compression. Personally, I find it false advertising, > but nobody's listening to me.
I tend to agree, especially now some makers are advertising based on 3:1 backup ratios.. I find that some LTO-2 tapes with only system and incremental backups (mostly logfiles, configfiles, sources and binaries, highly compressable) can get up to 700GB. IIRC one even topped 950GB (which I assumed must be wrong, but subsequent checks verified there really was that much on it), at which point I implemented "volume use duration" of 7 days. On the other hand, various data partition backups full of compressed files regularly only manage 205GB on the same 200GB LTO-2 tapes. It really does matter what you're trying to backup. If in doubt: ' tar - /path/to/root | gzip | wc ' vs ' tar - /path/to/root | wc ' ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users