Re: Database Backup Schedules

At 10:09 AM 5/3/95 -0500, Clem Akins wrote: >> From: 15SAS133.HQAMC@MHS.SAFB.AF.MIL (Davis, SrA Jeff) >> To: informix-list@rmy.emory.edu >> [clipped] >First, RTFM. OnLine Administrator's Guide (v5.0) pg3-40. Joe Lumbley's >book probably has good things to say (though I don't yet have a copy.) > >Now that we have a clue, here's the real deal... >We got a big digital linear tape (DLT) drive that holds 20GB, and we >do a level 0 every day. There are several things to beware of, though: > Informix won't support > tape-drive level compression This is something that I have never been able to understand. If your tape drive supports H/W compression, through a seperate device access (i.e. tx0 vs. tx0c), then why in the hell should Informix care?? This is completely outside of Informix, all ontape or OnArchive does is pump data to a device. If this device can, without addition calls, compress/uncompress the data as it writes and reads from the tape, who cares?? OnArchive now supports compression, though its S/W compression being done by OnArchive. This is going to slow down your archive times, since additional cycles are now required to perform the compression. On the otherhand, drive compression, is done at the tape drive device, and actually speeds up archive times. So, go figure........ > more than 1 archive per tape > (of course that doesn't mean you can't do it...) > There are bugs on the DEC Alpha & 7.1 when restoring from >1 tape Clem, could you shine a little light on your restore problem? Are you using ontape or OnArchive?? > (I don't know about other platforms) > You have to do real-life testing of your archives to be SURE they > work the way you think they do. > >BTW, are you just going to keep growing, or have you thought about a >way to purge off old records? > __________________________________________________________________ > | Clem Akins Standard Disclaimers Apply | > |Reynolds Metals Co, Alloys Plant "Climb High, Cave Deep!" | > | Muscle Shoals, Alabama USA cwakins@leia.alloys.rmc.com | > |________________________________________________________________| > > ================================================================== Jon Vemo Internet: jvemo@cyberspace.com Bothell, WA USA ------------------------------------------------------------------ Watch out for road-kill on the information superhighway....SPLAT!! ==================================================================