tag:blogger.com,1999:blog-4622775563416752930.post5387214188516903529..comments2022-09-01T20:53:27.194+01:00Comments on Mark's stream of verbiage: Migrating from MySQL 4.1 to 5.xMark Robsonhttp://www.blogger.com/profile/15864507044869250062noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-4622775563416752930.post-735006748093762512008-09-16T17:25:00.000+01:002008-09-16T17:25:00.000+01:00Another thing I did for rollback, was setup anothe...Another thing I did for rollback, was setup another 5.0 slave, with a bin log setup to start at the moment we upgraded to 5.0. If we had to fail back, which we didn't, I'd replay that log against a 4.1 server, adjusting for 5.0-only-isms.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4622775563416752930.post-66163678242871322342008-09-16T17:21:00.000+01:002008-09-16T17:21:00.000+01:00fat'n'happy: I don't understand how doing a backup...fat'n'happy: I don't understand how doing a backup of the files would help in any way.<BR/><BR/>We don't want to roll back to the data which existed before the upgrade, we want to be able to roll back to the old version of the software, preserving all data including stuff written following the deploymentMark Robsonhttps://www.blogger.com/profile/15864507044869250062noreply@blogger.comtag:blogger.com,1999:blog-4622775563416752930.post-22269431488011799092008-09-16T15:52:00.000+01:002008-09-16T15:52:00.000+01:00Mark,I did the same upgrade about 2 months ago. W...Mark,<BR/><BR/>I did the same upgrade about 2 months ago. We had a 300GB InnoDB database. Rollback with a dump and load was not an option. <BR/><BR/>What we did was setup a 5.0 slave and seeded with a mysqldump of the master and did an initial load into the 5.0 slave. (The only issues we ran into were utf8 data that had been encoded in latin1 tables on the 4.1 server. They were being double decoded in 5.0. I had to do a special import of those tables.)<BR/><BR/>During the actual upgrade it was a simple failover to the 5.0 as the master. The 4.1 former master was frozen in time as a rollback (You can't replicate from 5.0 to 4.1). As a final confirmation that our data was good, I wrote a couple of store procedures that performed a aggregated view of the data between the servers.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4622775563416752930.post-39951096363011503212008-09-16T13:21:00.000+01:002008-09-16T13:21:00.000+01:00Why not buy a couple of cheap terabyte hdd and do ...Why not buy a couple of cheap terabyte hdd and do a file level backup of the myisam data before the migration?Andrewhttps://www.blogger.com/profile/14300287758588566899noreply@blogger.com