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		<title>Is dedupe to tape crazy?</title>
		<description>Discuss Is dedupe to tape crazy?</description>
		<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html</link>
		<lastBuildDate>Fri, 10 Feb 2012 21:00:31 +0000</lastBuildDate>
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			<title>Sorry, I don\'t agree</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-758</link>
			<description><![CDATA[I don't have the negative view of tape that you have. Tape is very reliable if the system around it is designed properly. Tape also does not "stretch." The problem with tape is that people don't (or can't) architect for it properly. They've got a 180 MB/s tape drive that they're feeding 20 MB/s -- and they wonder why it fails. As to moving backups to tape after 30-45 days for the purposes of DR, I completely disagree. DR is done from yesterday's backups -- NEVER from backups from 30-45 days ago. If someone is moving something to tape after 30-45 days, it's for long term retention -- NOT DR. As to CAS being the ultimate long term solution, again I have to disagree. It's the most expensive way to store data long term -- often more expensive than not archiving it in the first place. The long term power costs alone are an order of magnitude greater than tape. And replicating CAS to a second location costs even more money. (And putting it in a colo makes it cost even more!) As to dedupe being untrusted, I think the sales of all of the dedupe products beg to differ. How is dedupe (offered by dozens of vendors) untrusted, but CAS (offered by two vendors) is trusted? (BTW, CAS is essentially dedupe. It's just object-level dedupe.) I still like tape for long term archiving -- if it is handled properly. That means retentioning every year and moving it to fresher, newer media every five years. If you don't want to have to do that, then go to optical. A 30 yr CAS archive? Holy cow would that cost a lot.]]></description>
			<dc:creator>W. Curtis Preston</dc:creator>
			<pubDate>Fri, 20 Nov 2009 14:21:34 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-758</guid>
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			<title>There is more to this than just deduplication</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-757</link>
			<description><![CDATA[An interesting topic. I have supported backups (Backup Exec / Netbackup) for over 10 years and I have been involved in the progression of the technologies and their growth and improvements over time. Here are the trends that I have seen: Although tape is not considered a reliable media for frequent backups (daily backups) due to the fact that it wears out from stretching and read / write processes, it is still heavily used. A lot of this has to do with the mind set of familiarity - it is a known media. Even though it fails, it is somewhat predictable in that failure. And it is cheap to keep spare tapes on hand to replace the failed tapes. Backing up to disk, whether directly or through a virtual tape library, is considered to be a new technology, despite the fact that it has been around for over 8 years. Deduplication has been around for 4 or 5 years, but is still largely misunderstood and untrusted (is that a proper word?). So to discuss deduping to disk instead of tape causes CIOs to shut down! :-) But here is the path that I have seen to work best and it encompasses more than just deduping: Backup to disk, using deduplication where possible. Deduplication is a process that can be done from either the source system (where the files are coming from) or by the target system (the system actually performing the deduplication). Retain the backups on disk for a period of x days (30 -45 is recommended), then move the FULLS to tape. Remember that at this point you are looking to this retention for DISASTER RECOVERY, not for deleted file restore. If there is a need for ARCHIVAL, tape is NOT the way to go. Instead, you should look to CAS (content addressed storage). Archival is for the purpose of retaining documents in their final form for an extended period of time (some as long as 30 years. If there is a concern about the data being available in the event of failure, there are several options available. Replication of data to a system that is distant from the main system is the best way to go. By distant, I am referring to over 100 miles apart. If you do not a facility that is distant, there are options, including &#34;renting&#34; the space for the system to hosted in. It is more important to do this than most companies think. And it is a topic that most of them do not want to address, largely because they do not understand the technology. I hope I am not adding confusion to this topic. The long and short of this is that deduplication to disk is the best way go. moving them to tape is an option, but in my opinion it is not the best way to go. It is better to protect the data through replication to a distant system and to look to CAS for long term, archival storage.]]></description>
			<dc:creator>Mark Bellows</dc:creator>
			<pubDate>Fri, 20 Nov 2009 14:01:39 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-757</guid>
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			<title>Toby Anderson says:</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-753</link>
			<description><![CDATA[Looks like the previous message was clipped somehow]]></description>
			<dc:creator>Toby Anderson</dc:creator>
			<pubDate>Thu, 29 Oct 2009 16:16:08 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-753</guid>
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			<title>Guessing here</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-754</link>
			<description><![CDATA[You were going to say "retentions significantly longer than that." So do I. What I'm saying is a waste of resources is people who use their backup apps as archive apps. They do a lousy job of it for many reason. Tthat is what ARCHIVE APPLICATIONS are for -- NOT backup applications. Backup apps for restoring deleted files. If you want to keep data for long periods of time and recall files based on context (e.g. all the files with the word "elvis" in them) then you need an archive app.]]></description>
			<dc:creator>W. Curtis Preston</dc:creator>
			<pubDate>Wed, 28 Oct 2009 17:24:42 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-754</guid>
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			<title>They\'re able to make multiple tape copies</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-752</link>
			<description><![CDATA[That's already built into the product. I agree. ;-)]]></description>
			<dc:creator>W. Curtis Preston</dc:creator>
			<pubDate>Wed, 28 Oct 2009 13:42:49 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-752</guid>
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			<title>devon peters says:</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-751</link>
			<description><![CDATA[Do you know if you're able to make multiple tape copies? I'd really hate to have a tape with deduped data on it fail.]]></description>
			<dc:creator>devon peters</dc:creator>
			<pubDate>Wed, 28 Oct 2009 13:09:07 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-751</guid>
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			<title>Performance</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-748</link>
			<description><![CDATA[David, If you're asking about restore performance from deduped tape, it didn't sound very good, but that's why you would only use it when deduping data that you don't plan on reading very much. Let me give you a scenario. Assume you've got a 30 tape set that has a file that was changed every day so pieces of that tape are on 30 different tapes. If you have to retrieve that file (notice I retrieve and not restore, because this is probably for an ediscovery case), you'll need to load and fast forward to the right spot on 30 tapes. That's at least an hour just to do that (assuming it was serial), but if you're only grabbing a few files here and there -- is that so bad? You're retrieving it for an ediscovery request that typically gives you days or weeks, not hours or minutes, to retrieve the data. Does it matter if it takes an hour to get the one file off tape? And, again, if you're retrieving a whole bunch of stuff for ediscovery, there are two ways to scan a set of tapes back in mass to make that much faster.]]></description>
			<dc:creator>W. Curtis Preston</dc:creator>
			<pubDate>Tue, 27 Oct 2009 16:43:01 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-748</guid>
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			<title>That\'s not what I said</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-747</link>
			<description><![CDATA[They recommend it for a very specific user case: the tapes you know you're making that you never plan to restore from. There are tons of people who make backups that they KNOW they're never going to use: &#34;We back up every day and some lawyer says we have to keep them for 7 years.&#34; I would suggest that the tapes older than 60 days and less than 7 years are never going to get read! They're saying dedupe those tapes. If you ever have to read from those tapes, they've got three different ways to do so. One is easy but takes a while if you're doing a LOT of files, and the other two take a little more setup time, but are much quicker once you do that setup. I really don't see the problem. Every product I know has places where it works well and places where it doesn't. They're saying that dedupe to tape works well in that use case. If you don't have that use case then don't use it. What's the problem with that?]]></description>
			<dc:creator>W. Curtis Preston</dc:creator>
			<pubDate>Tue, 27 Oct 2009 16:38:29 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-747</guid>
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			<title>david chapa says:</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-746</link>
			<description><![CDATA[I haven't had time to read this fully yet - on the road right now, but you don't mention the performance. what's the performance?]]></description>
			<dc:creator>david chapa</dc:creator>
			<pubDate>Tue, 27 Oct 2009 16:31:05 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-746</guid>
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			<title>re: Again, they would agree with you</title>
			<link>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-745</link>
			<description><![CDATA[ Which raises the "validity" of the business cases showing the Vault savings. It seems they're saying, "We can save you $X, but we wouldn't recommend you do it."]]></description>
			<dc:creator>Nick Cassimatis</dc:creator>
			<pubDate>Tue, 27 Oct 2009 09:40:59 +0000</pubDate>
			<guid>http://www.backupcentral.com/mr-backup-blog-mainmenu-47/13-mr-backup-blog/271-dedupe-to-tape-crazy.html#comment-745</guid>
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