Re: Logical Logs - store on tape, disk or to /dev/null?

On 8 Aug 1998 08:45:01 GMT, paulw@wfsoftware.co.uk (WF Software) wrote: >In article <35CB9067.4CDB7087@segel.NOSPAM-.KING.OF.MYDOMAIN.-NOSPAM.com>, >mikey@segel.NOSPAM-.KING.OF.MYDOMAIN.-NOSPAM.com (Mike Segel) wrote: > >> Stephan Stresing wrote: >> > >> > Hi, >> > recently I posted the onconfig of one of our client sites and one >> > comment I got was, if we were really not interested in the logical >> > logs because LTAPEDEV is set to /dev/null. This made me post this >> > message because I want to know how you handle this: are 2 tape devices >> > connected to your servers or are you storing the logs to disk? We have >> > set this option to /dev/null because our client only has 1 tape device >> > (changer) and usually they need it for the regular backup (filesystem >> > as well as database). >> > At our site we write the logs to disk and back them up every night, so >> > if we need them, we could restore them from our normal filesystem >> > back- >> > up set. >> > Now, it's your turn... :-) How do you handle this kind of "problem"? >> > TIA, >> >> Hmmmmmm. >> I don't think it is a problem per se. >> >Does setting the LTAPEDEV to /dev/null still put the engine into >continuous logging on restart? Surely if this is still the case and the >log fills then it will be marked as archived to /dev/null. So when you >come to a restore the engine will not allow you back out the logs to real >tape 'cos it thinks there are already archived somewhere. So aren't we >back at a level 0[12] restore with no log roll forward. > >I'm happy to be flamed over this view as I don't set LTAPEDEV to null This is true. So normally you would only set LTAPEDEV to /dev/null on a development machine where you don't care about the logs or on a production machine where you run without logging (that *is* ok in some cases). You need to set LTAPEDEV to /dev/null even if you run without logging as all DDL statements are logged anyway and would otherwise fill up your log. If you do not back up these logs you do of course need to know what DDL statements may need to be executed in case of a recovery from a backup. There may also be cases on a production server with logging where you would set LTAPEDEV to /dev/null. You might have turned on logging to enable rollback while you don't need the logs for backup. You better know what you are doing in this case of course. Nils Myklebust NM Data AS Norway E-mail: Nils.Myklebust@nmdata.com FAQ at: http://www.iiug.org/techinfo/faq/faq_top.html (Now with ODBC info under "Third party products".)