From: "Thomas T" Newsgroups: comp.databases.oracle.server References: <3f565f45$1@rutgers.edu> <3f570df5$0$14563$afc38c87@news.optusnet.com.au> Subject: Re: Enabling Archivelog mode, Oracle7- any issues? Date: Tue, 9 Sep 2003 15:10:21 -0400 Lines: 93 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 NNTP-Posting-Host: 165.230.189.212 Message-ID: <3f5e259f$1@rutgers.edu> X-Trace: rutgers.edu 1063134623 165.230.189.212 (9 Sep 2003 15:10:23 -0400) Path: newssvr20.news.prodigy.com!newsmst01.news.prodigy.com!prodigy.com!prodigy.com!logbridge.uoregon.edu!swen.emba.uvm.edu!att541!att542!ip.att.net!rutgers.edu!not-for-mail Xref: newssvr20.news.prodigy.com comp.databases.oracle.server:242719 "Howard J. Rogers" wrote in message news:3f570df5$0$14563$afc38c87@news.optusnet.com.au... > > "Thomas T" wrote in message news:3f565f45$1@rutgers.edu... > > Or should I just get a jump on things and add log_archive_dest to the > > init.ora before I even put the database into archivelog mode? Then I'd > just > > say "alter system archive log start"? (I believe this to be the right > > answer...?) > > > You believe correctly. > > The reason the doco doesn't say to add the "to" bit to the 'alter system > archive log start' command is that there is a default directory where it > ends up. It varies, I think, from platform to platform, but generally seems > to be (from memory) ORACLE_HOME/dbs/archive. If you end up with some > archived logs there, and some others in a different place because you > eventually get round to changing the log_archive_dest parameter, then it > isn't going to kill you. > > But the simplest thing to do is to get log_archive_start and > log_archive_dest set in your init.ora when you do your next cold backup. > When you restart your database, they will be set and ready to go. If on the > way to restarting your database, you were to stop off in mount state, and > issue the alter database archivelog command, then by the time you issue the > alter database open command, everything will already be working. > > > > > *One more question, while I'm at it. It looks like, once the archived > logs > > get put onto tape, I can delete them from the disk. I'd like to delete > them > > after 48 hours. Does that sound reasonable? > > Sort of. The more you can keep on disk, the happier you'll be (On the > grounds that restoring from tape can be a pain in the bottom, and recoveries > done from disk will be quicker, generally, than those from tape. Depends on > your tape drive, of course!), But the principle is that you can delete > anything if you've got a copy of it somewhere else first. > > >Or should I just leave them on > > the disk, keep an eye on disk usage, and delete old logfiles as I see fit? > > What if I need to recover (unlikely!) 96 hours previous- would I restore > the > > previous 48 hours of log files back onto the disk, and that, along with > the > > current 48 hours, would give me my total 96 hours to recover from? > > Correct. > > > > > Sorry to ask so many questions but I can't seem to find any of this in the > > literature I've read... > > I feel I've failed, in that case. But a new paper is on its way, anyway, and > I'll take these comments into mind when doing it. > > Regards > HJR Actually, your document expressed the information in a more clear manner then the books I'd read. It matched my notes (from my readings) so closely that I felt much more sure of myself (aside from the above questions) that I was running the right commands in the right order- so it was definately the most helpful! Plus, the copy I was referring to was probably out of date; it's revision 4.0.1, dated 22/05/2000. Combine that with running an old version of Oracle (7.3), and I can't complain! I enabled archive log last week, and everything's going smoothly. I just have to finish writing my scripts to take certain tablespaces offline on certain days; I plan to spread the tablespace backup across a week's worth of tapes. I'll just take a cold backup on Friday nights (really Saturday morning) instead of every day. I might change that opinion... seems like Monday's our busiest day for reporting. In that case, I might just take an export for the Friday tapes, and do a cold backup during the middle of the week (to keep the library and buffer cache filled with useful data). Thanks again, -Thomas