Hal, What about work in progress?
This is why we have logs, journals and WADS that track work in progress. Of course the logs have to be part of the same consistency group as the Database, but what you get is a copy of your application that can be backed up, restored, and used for restart. Having IO consistency means you have database consistency. Restarting from those Shadowimages will be just the same as restarting after a power failure, or starting up on a remote copy maintained with synch or asynch remote copy. The DB will start, and the logs will be use to apply updates or roll back uncommitted work. I have 5TB of Oracle Database in Taiwan where I use Hardware consistency Groups to spin off a backup and a reporting version of the database every day. Oracle runs against these two copies daily, and it has been running without a hitch for over 18 months. Oracle handles in-flight data pretty much the same way as DB2, where the logs are used to externalise committed data. Remember that DB2 doc is only going to talk about how to do it with IBM storage - that doesn't make it the only way, or the best way. IBM isn't going to write a redbook on hardware copies across multiple controllers and databases when the first paragraph says "start with two or more HDS Storage Controllers..." Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On > Behalf Of Hal Merritt > Sent: Thursday, 14 July 2005 3:49 AM > To: [email protected] > Subject: Re: DB2 and flashcopy2 > > What about the work in progress in DB2 buffers that is not yet committed > (flushed) to DASD? The I/O might be consistent, but how would the data? > > I would follow the suggestions in the DB2 doc rather than the hardware. > > Also, there is ample discussion in many recovery Redbooks that discuss > the 'Point of Consistency' concepts and issues. > > Only the Lone Ranger has Silver Bullets. > > My US$0.02 > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
