I am not talking whether putting DNS entry works, but am just pointing to the fact that oracle behaves differently if you put hardcoded IP - it than listens to one IP only, and if you put the dns name - listens to all IPs.
Djordje > -----Original Message----- > From: Rachel Carmichael [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, December 11, 2001 11:50 AM > To: Multiple recipients of list ORACLE-L > Subject: Re: Listeners listening to multiple IPs > > > it's not so much a feature of the listener as it is of DNS as far as I > know. One of the reasons it's best not to hard-code IP addresses into > the listener.ora is because when you do a failover, or > combine machines > as you have, the listener.ora and tnsnames.ora files need to be > updated. > > If you use DNS and let the DNS server resolve the address, you don't > have to change anything. > > This has been around for as long as I can remember using the listener, > which means going back to version 6 > > Rachel > > --- Djordje Jankovic <[EMAIL PROTECTED]> wrote: > > Something I learned today, but haven't seen it documented anywhere > > and would > > like to see whether anybody has come across it. > > > > We have a Sun server (call it oracle.acme.com). It came to life by > > combining two machines (oracle1.acme.com and oracle2.acme.com). So > > now it > > has two IP addresses: hme0: x.y.z.001 - from oracle1 and hme1: > > x.y.z.002 - > > from oracle2. There are few databases there (some of them were on > > oracle1 > > some on oracle2) and one listener listening to all of them. > > > > If you configure listener.ora file so that HOST=x.y.z.001, or > > HOST=x.y.z.002 > > that listener listens to that ONE IP only. However, if you put > > HOST=oracle.acme.com in listener.ora than it listens to all IPs (in > > netstat > > -an you see that it is listening to "*.1521" instead of to > > "oracle.acme.com.1521"). That would mean that oracle does not > > resolve DNS > > at replaces it with IP but first checks whether this is the primary > > IP for > > that box. > > > > So, once we have put HOST=oracle.acme.com, all the connections were > > OK > > (coming from clients with tnsnames files that are pointing to old > > oracle1.acme.com and oracle2.acme.com) Of course DNS was changed.. > > > > Anybody has come across this undocumented feature ? Any explanation > > to that > > ? > > > > Djordje > > -- > > Please see the official ORACLE-L FAQ: http://www.orafaq.com > > -- > > Author: Djordje Jankovic > > INET: [EMAIL PROTECTED] > > > > 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: [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). > > > __________________________________________________ > Do You Yahoo!? > Check out Yahoo! Shopping and Yahoo! Auctions for all of > your unique holiday gifts! Buy at http://shopping.yahoo.com > or bid at http://auctions.yahoo.com > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Rachel Carmichael > INET: [EMAIL PROTECTED] > > 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: [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.com -- Author: Djordje Jankovic INET: [EMAIL PROTECTED] 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: [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).
