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RE: Common Oracle RDBMS Misconceptions - standby db?

From: <Winnie_Liu_at_infonet.com>
Date: Wed, 27 Jun 2001 09:01:38 -0700
Message-ID: <F001.0033A2B1.20010627083718@fatcity.com>

Also check out the notes on metalink: #90817.1. It states all the steps and concept clearly!

Winnie

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(@ @) @}-`-,-`-,--- Winnie Liu ---'-,-'-,-{@ `~`~ / V \ Oracle Database Administrator `~`~ o--m-m--o Infonet Services Corporation `~`~ ##### mailto:winnie_liu_at_infonet.com `~`~ ~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~`~ mohammed bhatti To: Multiple recipients of list ORACLE-L <mkb125_at_yahoo <ORACLE-L_at_fatcity.com> .com> cc: Sent by: Subject: RE: Common Oracle RDBMS Misconceptions - root_at_fatcity. standby db? com 06/27/01 09:20 AM Please respond to ORACLE-L <tears of happiness> thank you, thank you, thank you... </tears of happiness> --- Jeremiah Wilton <jwilton_at_speakeasy.net> wrote: > With graceful standby failover (I demo'd it last > year at OOW), you can switch > back and forth, back and forth as many times as you > want without recopying any > database. > > Basically, when you fail over to a standby, you shut > down the primary, apply all > the archived redologs to the standby, then copy all > the online logs and the > controlfile from the primary to the standby. People > who use incremental > checkpoints (DB_BLOCK_MAX_DIRTY_TARGET) must do a > 'create controlfile reuse > database <blah> noresetlogs' at this point. Other > people don't have to. > > Finally, you "recover database" to get the last one > or two online logs and open > the standby "noresetogs." The standby just picks up > the chain of SCNs where the > primary left off. > > The old primary can be immediately pressed into > service as a standby. Just > generate a standby controlfile on the new primary, > copy it into place on the old > primary and start it up as a standby database. > > You can go back and forth in this way as many times > as you want, and one just > picks up the chain of SCNs where the last one left > off. You never get a > divergence of changes. > > I have talked to people who found this out, and > looked like they were going to > cry, thinking of the countless hours they had spent > after every standby > failover, recopying to the standby to get it rollong > forward again. > > In 9i, they have an "automated" graceful failover > mechanism for standby > database. I haven't taken a look at it yet. > Probably it is a massive > java-based GUI that instantly consumes 512Mb or RAM. > > -- > Jeremiah Wilton > http://www.speakeasy.net/~jwilton > > On Tue, 26 Jun 2001, Koivu, Lisa wrote: > > > OK. I admit my knowledge on standby is minimal, > having only read up on it, > > fiddled with it and used the idea sparingly for > migrations. > > > > However, Jeremiah, I'm very curious. You state > that 'Must reinstantiate > > standby after failover by recopying' is a > misconception. Yes, like many of > > the things you state below, the documentation does > say that - once you open > > a standby db in r/w mode, it is no longer a valid > standby after switching > > back to the primary. > > > > Can someone shed some light on why this is not > true? It seemed to make > > complete sense to me. I can see how opening a > database read only will work > > and not invalidate the standby, but r/w? > > -- > Please see the official ORACLE-L FAQ: > http://www.orafaq.com > -- > Author: Jeremiah Wilton > INET: jwilton_at_speakeasy.net > > Fat City Network Services -- (858) 538-5051 FAX: > (858) 538-5051 > San Diego, California -- Public Internet > access / Mailing Lists > -------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an > E-Mail message > to: ListGuru_at_fatcity.com (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). __________________________________________________ Do You Yahoo!? Get personalized email addresses from Yahoo! Mail http://personal.mail.yahoo.com/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: mohammed bhatti INET: mkb125_at_yahoo.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (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.com -- Author: INET: Winnie_Liu_at_infonet.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (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).
Received on Wed Jun 27 2001 - 11:01:38 CDT

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