It’s been a very mini-series but I hope I’ve highlighted some of the challenges when designing systems that need to recover from failures quickly. Here are a few ideas and I’m sure others could add their own.<\/p>\n
I mentioned in the previous part<\/a> that I would reach some unsatisfactory conclusions. Some of those are above – because I’m not telling you what to do, just mentioning some considerations – and here’s another. <\/p>\n There really is no one-size-fits-all solution and (slay me for saying this, purists) the chances are that you will not deliver what the business wants, or what you hoped you would, but a compromise resulting from the balance of risks, costs and expectations. Far better to turn around and admit that if things go very<\/i> wrong it might mean four hours down-time than come up with a pretty design document with the buzz-words that your managers are looking for and then have to spend four hours panicking when disaster strikes after the system’s live and five days explaining to managers why ‘it didn’t work’. <\/p>\n As for the satisfactory sources of information, here are a few.<\/p>\n I already mentioned Mogen’s first class critique of RAC<\/a> and I only recently came across another excellent RAC paper by James Morle that looks at RAC Connection Management<\/a>. Take a look at James’ paper and ask yourself if you understand what ‘Transparent Application Failover’ really means. It sounds<\/i> perfect, but I guess it doesn’t do what most of you would expect (unless you’ve worked with it already).<\/p>\n I’ve recently started reading the eBook version of Julian Dyke and Steve Shaw’s Pro Oracle Database 10g RAC on Linux<\/a>. Although I haven’t got into the guts of it yet, I’ve read all of the appendices and the first few chapters and the tone is pretty much what I’ve used in this series, but much more detailed. It’s very strong on high availability concepts so if you’ve never worked in that type of environment before, it’s a nice way to get started.<\/p>\n Oh, one more thing. Vidya asked about disk-to-disk synchronisation and I thought I’d include a link<\/a> for anyone who’s interested in that kind of thing, although it’s clearly vendor-specific<\/p>\n The series is finished for now, but I think there’ll be future blogs about how the implementation of the new system goes, particularly any problems I run into.<\/p>\n Looks like I’ll be back on PX for a couple of weeks 😉<\/p>\n","protected":false},"excerpt":{"rendered":" It’s been a very mini-series but I hope I’ve highlighted some of the challenges when designing systems that need to recover from failures quickly. Here are a few ideas and I’m sure others could add their own. Careful planning is essential. Ask tough questions and imagine the worst. Always be aware of the requirements. The… Continue reading Recovery Design Part 5 – Wrap-up<\/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-1124","post","type-post","status-publish","format-standard","hentry","category-uncategorized","entry"],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":1191,"url":"http:\/\/orcldoug.com\/blog\/2007\/01\/27\/dba-documentation-catalogue\/","url_meta":{"origin":1124,"position":0},"title":"DBA Documentation – Catalogue","date":"January 27, 2007","format":false,"excerpt":"Prompted by Linda's comment on a previous blog, I thought it might be worth writing a couple of postings on DBA documentation.The first thing you need is a Database Catalogue of some kind.Benefits1) Even an experienced DBA arriving on site won't know what servers exist, how to login to them,\u2026","rel":"","context":"With 11 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1382,"url":"http:\/\/orcldoug.com\/blog\/2008\/02\/22\/how-useful-are-diagnosticoptimization-tools-another-view\/","url_meta":{"origin":1124,"position":1},"title":"“How useful are diagnostic\/optimization tools?” – Another View","date":"February 22, 2008","format":false,"excerpt":"There have been a couple of very interesting blog postings over the past few weeks from Daniel Fink and Alex Gorbachev, prompted by a panel discussion at last week's RMOUG conference. Well, I suspect the panel was prompted by an earlier blog posting and many late night conversations. I've just\u2026","rel":"","context":"With 25 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/1124","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=1124"}],"version-history":[{"count":0,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/1124\/revisions"}],"wp:attachment":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/media?parent=1124"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/categories?post=1124"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/tags?post=1124"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}