{"id":3204,"date":"2011-07-06T22:12:02","date_gmt":"2011-07-06T12:12:02","guid":{"rendered":"http:\/\/nsrd.info\/blog\/?p=3204"},"modified":"2018-12-11T15:00:13","modified_gmt":"2018-12-11T05:00:13","slug":"why-tape-and-dedupe-just-dont-mix","status":"publish","type":"post","link":"https:\/\/nsrd.info\/blog\/2011\/07\/06\/why-tape-and-dedupe-just-dont-mix\/","title":{"rendered":"Why tape and dedupe just don’t mix"},"content":{"rendered":"

In “Tape and dedupe: So not happening \u2022 The Register<\/a>“, Chris Mellor asks:<\/p>\n

Why haven’t more vendors followed CommVault in putting deduped data on tape? Is it technically too hard?<\/p><\/blockquote>\n

There’s a good reason for this \u2013 it’s pretty nutty. Whether we wish it or not, tape is designed for large scale high speed sequential<\/em> access. Dedupe requires high speed random access in order to rehydrate. Some time ago I wrote a rebuttal to Curtis Preston’s overly generous appraisal of CommVault’s dedupe to tape strategy, and I still stand by every word I wrote there<\/a>.<\/p>\n

To be fair, Chris quotes someone who puts the argument very succinctly:<\/p>\n

Steve Mackey, SpectraLogic’s sales veep for Europe and Africa, says: “The issue of dedupe is recovery. You’ve got to recover the whole tape or a set of tapes before you can recover a file. The big users of archive are looking to recover the data. Today I don’t believe dedupe on tape meets the requirements for recovery.”<\/p><\/blockquote>\n

Dedupe to tape is crazy. Unless we can somehow overcome the sequential access nature of tape, it will stay crazy, too. That’s why tape and dedupe generally isn’t happening.<\/p>\n

And I’m glad that’s the case.<\/p>\n","protected":false},"excerpt":{"rendered":"

In “Tape and dedupe: So not happening \u2022 The Register“, Chris Mellor asks: Why haven’t more vendors followed CommVault in…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3,5],"tags":[298,806,980],"class_list":["post-3204","post","type-post","status-publish","format-standard","hentry","category-architecture","category-backup-theory","tag-dedupe","tag-rehydration","tag-tape"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pKpIN-PG","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts\/3204","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/comments?post=3204"}],"version-history":[{"count":1,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts\/3204\/revisions"}],"predecessor-version":[{"id":7504,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts\/3204\/revisions\/7504"}],"wp:attachment":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/media?parent=3204"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/categories?post=3204"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/tags?post=3204"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}