Message-Id: <10522.108244@fatcity.com> From: "Durinda.Jones" Date: Thu, 8 Jun 2000 10:59:44 -0500 Subject: RE: Fail over database James, I've added an additional address to my alias in the tnsnames.ora file to let it fall through to the other address. The only issue is with the lag time due to TCPIP, but it will fall through and connect to the second address. Take a look at the following document. I think it should do the trick. Durinda Jones Yellow Technologies Bookmark Fixed font Go to End Doc ID: Note:1015057.4 Subject: DOES SQL*NET SUPPORT REDUNDANT ALIASES? Type: PROBLEM Status: PUBLISHED Content Type: TEXT/PLAIN Creation Date: 25-JUN-1996 Last Revision Date: 17-JUL-1996 Language: USAENG Problem Description: ==================== Can SQL*Net have the same alias twice in the TNSNAMES.ORA with the first connecting to the primary host, and if that is not available, it switches to the other host. Solution: SQL*NET DOES NOT SUPPORT REDUNDANT ALIASES Solution Description: ===================== SQL*Net does not support redundant aliases. It will try the first alias and ignore the second alias. SQL*Net does support multiple addresses in one alias. If the first address fails, it will try the second. Example follows: alias.world = (description= (address_list = (address = (protocol = SPX) (service = ) ) (address = (protocol = TCP) (host = ) (port = ####) ) (connect_data = (sid = ) ) ) -----Original Message----- From: James Nailos [mailto:nails41175@yahoo.com] Sent: Thursday, June 08, 2000 9:52 AM To: oracledba Subject: RE: Fail over database Unfortunately using a standby database is not going to work for us. We are using Vignette Story Server, which has machine specific information on a couple of it's tables. So, those tables must be maintained separately on each machine. From what I understand it is not possible to maintain separate tables on a standby database. Does anyone have any suggestions to how I would switch to another database without using a standby database or load balancing? Basically, I need someway to detect that our production database is not accessible, and then switch the alias in my tnsnames to point to the backup database (or something to the effect of this). We are using Solaris machines, so I know that I can set up a daemon to do this. But, I was wondering if there was an easier way to do it through Oracle. Thanks, Jim --- Andrew Clarke wrote: > The syntax is straightforward: ALTER DATABASE > STANDBY DATABASE > .....etc. see > http://technet.oracle.com/doc/oracle8i_816/server.816/a76989/ch4b3.htm#20507 > for details. > > However, you should think carefully about the > benefits of this approach. > True, it provides an instant take-up of service when > your main db server > crashes; however it is the devil's own job to switch > back to the original > server oncen the fault is fixed. > > At my place we have ended up with an SLA where in > the event of catastrophic > failure service would be completely withdrawn for up > to four hours before we > switch over to the standby server! So the standby > server is rather a waste > of money; whereas a distributed system with both > servers on-line gives you a > more practical form of resilience, plus performance > benefits from load > balancing. > > the O'Reilly book on Oracle Distributed System > http://www.oreilly.com/catalog/ordistsys/ is well > worth a look before you > decide to spend all that money on a standby db > server. > > regards, APC > > -----Original Message----- > From: James Nailos [mailto:nails41175@yahoo.com] > Sent: 06 June 2000 23:25 > To: oracledba > Subject: Fail over database > > > I am trying to create a fail over database that is > replicated from a production database of ours. I > want to switch to the fail over database if our > production database does not respond. I was > wondering if any of you might know an easy way to > set > a fail over database with out just load balancing > the > two in the tnsnames.ora file? I do not want to > load > balance, I want the fail over database to just sit > there with no one hitting it accept for when it is > replicated. > > Thanks, > Jim > > __________________________________________________ > Do You Yahoo!? > Yahoo! Photos -- now, 100 FREE prints! > http://photos.yahoo.com > > -------- > If you're bored, then visit the list's website: > http://www.lazydba.com (updated daily) > to unsubscribe, send a blank email to > oracledba-unsubscribe@quickdoc.co.uk > to subscribe send a blank email to > oracledba-subscribe@quickdoc.co.uk > __________________________________________________ Do You Yahoo!? Yahoo! Photos -- now, 100 FREE prints! http://photos.yahoo.com -------- If you're bored, then visit the list's website: http://www.lazydba.com