Our Prod SAP system has 4 RAID1's dedicated to redo of 500m each on an Clariion CX600 SAN.
Several groups with 2 members each. That's 600 gig of physical disk dedicated to redo, and nothing else. Jared On Thu, 2003-07-31 at 04:59, Boivin, Patrice J wrote: > We use a SAN. > > Where does that leave me? > > : ) > > Patrice. > > -----Original Message----- > Sent: Wednesday, July 30, 2003 7:10 PM > To: Multiple recipients of list ORACLE-L > > > I'm constantly amazed (and relieved!) that there's disagreement on the > most fundamental principles. > > First, I found myself nodding at Roy's first post. On some databases, > I have three log groups, with two members each. Each set of members > has its own disk. I'll concede the argument that the instance goes > down right away if one of the drives fails, but I _still_ have a full > set of logs on the other drive, and that's a good thing, right? > > Second, if I have three groups of two members each and follow what > seems to be the consensus opinion, I have three drives, each holding > two members, one from each group. In this case, aren't the two members > on the same drive identical? If I lose that drive, I lose that entire > log group, and therefore no longer have a full set of logs--so what's > the point of having two copies? I also lose the instance immediately > if that group happens to be the current group at the time of disk > failure. > > Third, while I agree that every member of every group should ideally > have its own disk, does ANYONE actually configure their DB this way? I > had a hard enough time dedicating one or two disks to redo logs; who > can dedicate eight, especially given drive sizes of 72+ GB and (single) > log file sizes of, what, 100 MB? > > > > > --- "Pardee, Roy E" <[EMAIL PROTECTED]> wrote: > > Yep, that's right--I had it wrong. You need to have at least one > > member from each group in order to do a full recovery. I see now > > from my trusty dba fundamentals I class text that each member of a > > group is identical (or is supposed to be). > > > > So I guess I'll go back to being confused about why the answer to the > > question below is 2. I guess 2 is the minimum required to survive a > > single disk failure? > > > > Cheers, > > > > -Roy > > > > Roy Pardee > > Programmer/Analyst/DBA > > SWFPAC Lockheed Martin IT > > Extension 8487 > > > __________________________________ > Do you Yahoo!? > Yahoo! SiteBuilder - Free, easy-to-use web site design software > http://sitebuilder.yahoo.com > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Paul Baumgartel > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Boivin, Patrice J > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jared Still INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
