{"id":1108,"date":"2006-10-29T12:00:00","date_gmt":"2006-10-29T12:00:00","guid":{"rendered":"http:\/\/orcldoug.com\/blog\/?p=1108"},"modified":"2006-10-29T12:00:00","modified_gmt":"2006-10-29T12:00:00","slug":"recovery-design","status":"publish","type":"post","link":"http:\/\/orcldoug.com\/blog\/2006\/10\/29\/recovery-design\/","title":{"rendered":"Recovery Design"},"content":{"rendered":"<p>I sometimes think that a blog seems incomplete unless the author whines about how busy they&#8217;ve been recently. It would be easy to miscontrue that as a plea for sympathy. Maybe it is sometimes but another strong possibility is that it arises from mild feelings of guilt about posting frequency. There&#8217;s no <i>reason<\/i> to feel guilty, but some of us feel unreasonably guilty from time to time &#128577; It&#8217;s the parents to blame, I reckon &#128521;<\/p>\n<p>Either way, I&#8217;ve been extremely busy over the past month, but at least work has provided potential blog material if not the time to blog it. That&#8217;s more than enough whining and on to a subject that&#8217;s always interested me &#8211; <i>Recovery Design<\/i>. <\/p>\n<p>I thought long and hard over that description and there were other candidates I might have chosen &#8211; Disaster Recovery Planning and Designing Highly Available Systems are just a couple, or readers could fill in their own favourite. I&#8217;ll explain the requirements a little.<\/p>\n<p>We&#8217;re implementing a new system consisting of perhaps 20-30 servers including five databases. In fact the Oracle components appear at first sight to be a small part<br \/>\nof the architecture but the simple fact that two of the databases can&#8217;t<br \/>\nsuffer an outage of more than a few minutes is an indication that<br \/>\nthey&#8217;re a small but probably critical component.<\/p>\n<ul>\n<li>A two server cluster containing two databases with a maximum down-time of 5 minutes<\/li>\n<li>A two server cluster hosting two databases with a maximum down-time of 30 minutes<\/li>\n<li>A two server cluster hosting a single database with a maximum down-time of 6 hours.<\/li>\n<\/ul>\n<p> In all cases, there are application components on the servers too.<\/p>\n<p>I&#8217;m not going to go into much detail about the purpose of the system, to preserve client confidentiality, although I&#8217;d love to because it&#8217;s fascinating. Suffice to say it&#8217;s a system that thousands of customers will connect to directly rather than being an internal business system. <\/p>\n<p>My current client takes a pretty enlightened approach to designing systems like this. Although all of the software is being provided by third parties, those companies, the company&#8217;s internal technical experts and business representatives work on the initial high level design together before the expenditure is signed off and the implementation can begin. For example, it&#8217;s very difficult to establish the maximum down-time for a component without involving technical and business people. (Even then, it wasn&#8217;t easy!) I became involved as the Oracle guy and my first task was to review the third-party&#8217;s technical design.<\/p>\n<p>Next up, I&#8217;ll look at that initial design and the tough questions I asked. For now, I&#8217;m off to put together my latest version of the technical design. It might be Sunday and I&#8217;m not supposed to be working, but deadlines are tight and I enjoy the work anyway &#128521;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I sometimes think that a blog seems incomplete unless the author whines about how busy they&#8217;ve been recently. It would be easy to miscontrue that as a plea for sympathy. Maybe it is sometimes but another strong possibility is that it arises from mild feelings of guilt about posting frequency. There&#8217;s no reason to feel&hellip; <a class=\"more-link\" href=\"http:\/\/orcldoug.com\/blog\/2006\/10\/29\/recovery-design\/\">Continue reading <span class=\"screen-reader-text\">Recovery Design<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1108","post","type-post","status-publish","format-standard","hentry","category-uncategorized","entry"],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":1423,"url":"http:\/\/orcldoug.com\/blog\/2008\/08\/03\/dude-its-a-blog\/","url_meta":{"origin":1108,"position":0},"title":"dude &#8211; it&#8217;s a blog","date":"August 3, 2008","format":false,"excerpt":"Well, I'm back from two weeks holiday away from the net and a pile of blog comments and emails to catch up on. I'll leave those for tomorrow. A quickie for now, though. I see that Kurt van Meerbeeck (yeah, OK, Kurt the DUDE guy) has finally started a blog.\u2026","rel":"","context":"Similar post","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1114,"url":"http:\/\/orcldoug.com\/blog\/2009\/10\/30\/recovery-design-part-2-asking-the-right-questions\/","url_meta":{"origin":1108,"position":1},"title":"Recovery Design part 2 &#8211; Asking the right questions","date":"October 30, 2009","format":false,"excerpt":"In the previous blog in this mini-series, I arrived into the project and was asked to review the external vendor's initial High Level Design (HLD). As stated previously, there are a total of five Oracle databases in the system architecture. All will be running on 10g which is good news\u2026","rel":"","context":"Similar post","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1544,"url":"http:\/\/orcldoug.com\/blog\/2009\/11\/22\/advert-busy-busy\/","url_meta":{"origin":1108,"position":2},"title":"Advert: Busy, Busy &#8230;","date":"November 22, 2009","format":false,"excerpt":"A quick post from a hotel room in Bratislava (and very nice both are, too, although it's difficult to judge a city in the dark) .... Tomorrow I'm teaching the 2-day performance course for Oracle University.Next week I'm giving two presentations at the annual UKOUG conference in Birmingham (Alex, Marco\u2026","rel":"","context":"With 6 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1072,"url":"http:\/\/orcldoug.com\/blog\/2006\/08\/31\/if-youre-gonna-screw-up\/","url_meta":{"origin":1108,"position":3},"title":"If you&#8217;re gonna screw up &#8230;","date":"August 31, 2006","format":false,"excerpt":"... you should always aim high (or desperately low would be more accurate). I was sitting at my desk today, deleting some old databases (that phrase in itself should be warning enough) when I typed in the followingdunha1e:oracle#rm -fR *I looked down at my notes to have a think about\u2026","rel":"","context":"With 28 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1464,"url":"http:\/\/orcldoug.com\/blog\/2008\/12\/18\/performance-on-my-mind\/","url_meta":{"origin":1108,"position":4},"title":"Performance on my mind &#8230;","date":"December 18, 2008","format":false,"excerpt":"I've been a bit busy recently because I've had a rolling 4 week cold (like lots of people in the office - obviously several colds in quick succession), a couple of presentations at UKOUG (where I'm sure the additional beer didn't help recovery) and then I was in Vienna on\u2026","rel":"","context":"With 3 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1590,"url":"http:\/\/orcldoug.com\/blog\/2010\/03\/28\/statistics-on-partitioned-tables-contents\/","url_meta":{"origin":1108,"position":5},"title":"Statistics on Partitioned Tables &#8211; Contents","date":"March 28, 2010","format":false,"excerpt":"When Jonathan Lewis decided it was time to post a list of the Partition Stats posts on his blog and Noons suggested I made them easier to track down, I listened. So this post will link to the others and, at least in the short term, I've also included links\u2026","rel":"","context":"Similar post","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/1108","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/comments?post=1108"}],"version-history":[{"count":0,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/1108\/revisions"}],"wp:attachment":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/media?parent=1108"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/categories?post=1108"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/tags?post=1108"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}