{"id":1586,"date":"2010-01-06T06:41:26","date_gmt":"2010-01-05T20:41:26","guid":{"rendered":"http:\/\/nsrd.info\/blog\/?p=1586"},"modified":"2010-01-06T06:41:26","modified_gmt":"2010-01-05T20:41:26","slug":"the-top-10-for-2009","status":"publish","type":"post","link":"https:\/\/nsrd.info\/blog\/2010\/01\/06\/the-top-10-for-2009\/","title":{"rendered":"The top 10 for 2009"},"content":{"rendered":"<p>Looking at the stats both for this new site and the previous site, I&#8217;ve compiled a list of the top 10 read articles on <em>The NetWorker Blog<\/em> for 2009. The top 3 of course match the three articles that routinely turn out to be the most popular on any given month, which speaks something of their relevance to the average NetWorker administrator.<\/p>\n<p>(Note: I&#8217;ve excluded non-article <em>pages<\/em> from the top 10.)<\/p>\n<h3>Number 10 \u2013 Instantiating Savesets<\/h3>\n<p>The very first article on the blog, <a title=\"Instantiating Savesets\" href=\"https:\/\/nsrd.info\/blog\/2009\/01\/25\/instantiating-savesets\/\" target=\"_blank\">Instantiating Savesets<\/a> detailed the importance of distinguishing between <em>all instances of a saveset<\/em> and a <em>specific instance of a saveset<\/em>.<\/p>\n<p>This distinction between using just the saveset ID, and using a saveset ID\/clone ID combination becomes particularly important when staging from disk backup units. If clones exist and you stage using <em>just<\/em> the saveset ID, when NetWorker cleans up at the end of the staging operation it will remove reference to the clones as well as deleting the original from the disk backup unit. (Something you <em>really<\/em> don&#8217;t want to have happen.)<\/p>\n<p><strong>Recommendation to EMC<\/strong>: Perhaps it would be worthwhile requiring a &#8220;-y&#8221; argument to <em>nsrstage<\/em> if staging savesets from disk backup units and specifying only the saveset ID.<\/p>\n<p><strong>Recommendation to NetWorker administrators<\/strong>: Always be careful when staging that you specify both the saveset and the clone ID.<\/p>\n<h3>Number 9 \u2013 Basics \u2013 Important mminfo fields<\/h3>\n<p>In May I wrote about <a title=\"Basics - Important mminfo fields\" href=\"https:\/\/nsrd.info\/blog\/2009\/05\/27\/basics-important-mminfo-fields\/\" target=\"_blank\">a few key mminfo<\/a> fields \u2013 notably:<\/p>\n<ul>\n<li>savetime<\/li>\n<li>sscreate<\/li>\n<li>ssinsert<\/li>\n<li>sscomp<\/li>\n<li>ssaccess<\/li>\n<\/ul>\n<p>Sadly, I didn&#8217;t get the result I wanted with EMC on <em>ssaccess<\/em>. Documented as being updated whenever a saveset fragment is accessed for backup and recovery, the most I could get was an acknowledgement that it was currently broken and to lodge an RFE to get it fixed. (The alternative was to have the documentation changed to take out reference to read operations \u2013 something I didn&#8217;t want to have happen!)<\/p>\n<p><strong>Recommendation to EMC<\/strong>: ssaccess would be a particularly useful mminfo field, particularly when analysing recovery statistics for NetWorker. Please fix it.<\/p>\n<h3>Number 8 \u2013 Basics \u2013 Listing files in a backup<\/h3>\n<p>Want to know what files were <a title=\"Basics - Listing files in a backup\" href=\"https:\/\/nsrd.info\/blog\/2009\/01\/27\/basics-listing-files-in-a-backup\/\" target=\"_blank\">backed up as part of the creation of a saveset<\/a>? If you do, you&#8217;re not unique \u2013 this has remained a very popular article since it was written in January.<\/p>\n<p><strong>Recommendation to EMC<\/strong>: This information can be retrieved via a combination of mminfo\/nsrinfo, but it would be handy if NMC supported drilling down into a saveset to provide a file listing.<\/p>\n<h3>Number 7 \u2013 Using yum to install NetWorker on Linux<\/h3>\n<p>NetWorker&#8217;s need for dependency resolution on Linux for installation of the client packages in particular drew a lot of people to <a title=\"Using yum to install NetWorker on Linux\" href=\"https:\/\/nsrd.info\/blog\/2009\/05\/26\/using-yum-to-install-networker-on-linux\/\" target=\"_blank\">this article<\/a>.<\/p>\n<h3>Number 6 \u2013 Basics \u2013 mminfo, savetime, and greater than\/less than<\/h3>\n<p>This article explained why NetWorker uses the greater than and less than signs in mminfo in a way that newcomers to the product might find backwards. If you&#8217;re not aware of why mminfo works the way it does for <a title=\"Basics - mminfo, savetime and greater than\/less than\" href=\"https:\/\/nsrd.info\/blog\/2009\/02\/01\/basics-mminfo-savetime\/\" target=\"_blank\">specifying savetimes, you should be<\/a>.<\/p>\n<h3>Number 5 \u2013 7.5(.1) changed behaviour \u2013 deleting savesets from adv_file devices<\/h3>\n<p>This was a particularly unpleasant bug introduced into NetWorker 7.5, thankfully resolved now in the cumulative service releases <em>and<\/em> NetWorker 7.6<\/p>\n<p>The gist of it is that in NetWorker 7.5\/7.5.1 (aka 7.5 SP1), if you deleted a saveset on a disk backup unit, NetWorker would suffer a serious failure where it would from that point have issues cleaning regular expired savesets from the disk backup unit <em>and<\/em> insist that the disk backup unit had major issues. The primary error would manifest as:<\/p>\n<p><em><strong>nsrd adv_file warning: Failed to fetch the saveset(ss_t) structure for ssid 1890993582<\/strong><\/em><\/p>\n<p>This was fixed in 7.5.1.2, thankfully.<\/p>\n<p><strong>Recommendation to EMC<\/strong>: Never let this bug see the light of day again, please. (So far you&#8217;re doing an excellent job, by the way.)<\/p>\n<h3>Number 4 \u2013 NetWorker 7.5.1 Released<\/h3>\n<p>I&#8217;ve recently noticed a disturbing trend among many vendors, EMC included, where once a new release is made of a product, sales and account staff become overly enthusiastic about recommending new releases. This comes on top of not really having any technical expertise. (Please be patient, I&#8217;m trying to put this as diplomatically as possible.)<\/p>\n<p>One of the worst instances I&#8217;ve seen of this in the last few years was the near-hysterical pumping of 7.5 thanks to some useful features to do with virtualisation in particular. I&#8217;ll admit that my articles on the<a title=\"NetWorker 7.5 and Oracle Module 5\" href=\"https:\/\/nsrd.info\/blog\/2009\/05\/07\/networker-75-and-oracle-module-5\/\" target=\"_blank\"> integration between Oracle Module 5 and NetWorker 7.5<\/a>, as well as <a title=\"Using probe based backups in NetWorker\" href=\"https:\/\/nsrd.info\/blog\/2009\/01\/25\/using-probe-based-backups-in-networker\/\" target=\"_blank\">Probe Based Backups<\/a> may have added to this. However, there was somewhat of a stampede to 7.5 when it came out, and consequently, when it had some issues, there was strong enthusiasm for the release of 7.5.1.<\/p>\n<p>This is why, by the way, that IDATA maintains for its support customers a recommended versions list that <em>is not automatically updated when new versions of products come out<\/em>.<\/p>\n<p><strong>Recommendation to EMC<\/strong>: Remind your sales staff that existing users already <em>have<\/em> the product, and not to just go blindly convincing them to upgrade. Otherwise you&#8217;ll eventually start sounding like <a title=\"Broken Promises Get a Mac Ad\" href=\"http:\/\/movies.apple.com\/media\/us\/mac\/getamac\/2009\/apple-mvp-broken_promises-us-20091023_480x272.mov\" target=\"_blank\">this<\/a>.<\/p>\n<h3>Number 3 \u2013 Carry a jukebox with you (if you&#8217;re using Linux)<\/h3>\n<p>During 2009, Mark Harvey&#8217;s <a title=\"LinuxVTL\" href=\"http:\/\/linuxvtl.googlepages.com\" target=\"_blank\">LinuxVTL<\/a> project first got the open source LinuxVTL working with NetWorker in a <a title=\"Carry a jukebox with you (if you're using Linux)\" href=\"https:\/\/nsrd.info\/blog\/2009\/07\/13\/carry-a-jukebox-with-you-if-youre-using-linux\/\" target=\"_blank\">single drive configuration<\/a>, then eventually, in <a title=\"NetWorker and LinuxVTL, Redux\" href=\"https:\/\/nsrd.info\/blog\/2009\/11\/14\/networker-and-linuxvtl-redux\/\" target=\"_blank\">multi-drive configurations<\/a>. (Mark assures me, by the way, that patches are coming real soon to allow multiple robots on the same storage node\/server.)<\/p>\n<p><strong>Lesson for me<\/strong>: With the LinuxVTL configured on multiple lab servers in my environment, I&#8217;ve really taken to VTLs this year, and considerably changed my attitude on using them. (I&#8217;ll say again: I still resent that they&#8217;re needed, but I now respect them a lot more than I previously did.)<\/p>\n<p><strong>Lesson for others<\/strong>: Even Mark himself <a title=\"Mark Harvey on LinuxVTL\" href=\"https:\/\/nsrd.info\/blog\/2009\/11\/14\/networker-and-linuxvtl-redux\/comment-page-1\/#comment-453\" target=\"_blank\">says that the open source VTL shouldn&#8217;t be used for production backups<\/a>. Don&#8217;t be cheap with your backup system, this is an excellent tool for lab setups, training, diagnostics, etc., but it is <em>not<\/em> a replacement to a production-ready VTL system. If you want a VTL, <em>buy<\/em> a VTL.<\/p>\n<h3>Number 2 \u2013 Basics \u2013 Parallelism in NetWorker<\/h3>\n<p>Some would say that the high popularity of <a title=\"Basics - Parallelism in NetWorker\" href=\"https:\/\/nsrd.info\/blog\/2009\/02\/17\/basics-parallelism-in-networker\/\" target=\"_blank\">an article about parallelism in NetWorker<\/a> indicates that it&#8217;s not sufficiently documented.<\/p>\n<p>I&#8217;m not <em>entirely<\/em> convinced that&#8217;s the case. But it does go to show that it&#8217;s an important topic when it comes to performance tuning, and summary articles about how the various types of parallelism interact are obviously popular.<\/p>\n<p><strong>Lesson for everyone<\/strong>: Now that the performance tuning guide has been updated and made more relevant in NetWorker 7.6, I&#8217;d recommend people wanting an official overview of <em>some <\/em>of the parallelism options checking that out in addition to the article above.<em> <\/em><\/p>\n<h3>Number 1 \u2013 Basics \u2013 Fixing &#8220;NSR peer information&#8221; errors<\/h3>\n<p>Goodness this was a popular article in 2009 \u2013 <a title=\"Basics \u2013\u00a0Fixing NSR peer information errors\" href=\"https:\/\/nsrd.info\/blog\/2009\/02\/23\/basics-fixing-nsr-peer-information-errors\/\" target=\"_blank\">detailing how to fix the &#8220;NSR peer information&#8221; errors<\/a> that can come up from time to time in the NetWorker logs. If you&#8217;re not familiar with this error yet, it&#8217;s likely you will eventually as a NetWorker administrator see an error such as:<\/p>\n<p><em>39078 02\/02\/2009 09:45:13 PM\u00a0 0 0 2 1152952640 5095 0 nox nsrexecd SYSTEM error: There is already a machine using the name: \u201cfaero\u201d. Either choose a different name for your machine, or delete the \u201cNSR peer information\u201d entry for \u201cfaero\u201d on host: \u201cnox\u201d <\/em><\/p>\n<p><strong>Recommendation for EMC<\/strong>: Users shouldn&#8217;t really need to be Googling for a solution to this problem. Let&#8217;s see an update to NetWorker Management Console where these errors\/warnings are reported in the monitoring log, with the administrator being able to right click on them and choose to clear the peer information after confirming that they&#8217;re confident no nefarious activity is happening.<\/p>\n<h3>Wrapping Up<\/h3>\n<p>I have to say, it was a fantastically satisfying year writing the blog, and I&#8217;m looking forward to seeing what 2010 brings in terms of most useful articles.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Looking at the stats both for this new site and the previous site, I&#8217;ve compiled a list of the top&hellip;<\/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":[3,6,16,18,22,23],"tags":[66,72,227,307,313,540,594,602,1249,649,656,677,699,718,857,859,861,922,924,925,928,929,933,1101,1124],"class_list":["post-1586","post","type-post","status-publish","format-standard","hentry","category-architecture","category-basics","category-networker","category-quibbles","category-site","category-support","tag-7-5","tag-7-5-1","tag-clone-id","tag-deleting-savesets","tag-dependencies","tag-linux-vtl","tag-mminfo","tag-most-popular","tag-networker","tag-nsr-peer","tag-nsrclone","tag-nsrstage","tag-open-source-vtl","tag-parallelism","tag-saveset-id","tag-savesetss_t","tag-savetime","tag-ssaccess","tag-sscomp","tag-sscreate","tag-ssid","tag-ssinsert","tag-staging","tag-vtl","tag-yum"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pKpIN-pA","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts\/1586","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=1586"}],"version-history":[{"count":0,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/posts\/1586\/revisions"}],"wp:attachment":[{"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/media?parent=1586"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/categories?post=1586"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nsrd.info\/blog\/wp-json\/wp\/v2\/tags?post=1586"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}