Re: Use of offset 0 with AIX

Hi Malcolm Would be good if you tell us the vresion of AIX and IDS of your customer. I was using AIX 4.3.3 and 5.2 with LV (raw devices) for chunks and setting 0 to offset and I had never problems even when I restored instances. Best regards. Ferronato malcolm weallans escreveu: > I have just been through a DR situation on one of our customer sites that > had offset 0 for some chunks. And the recovery process couldn't rebuild > some of the chunks correctly. And the ones it had problems with were those > that had offset set to 0. In those cases the Logical Volume Manager > complained that the Logical Volume Control Block was corrupted. Fortunately > this was on their test server. > > I know many of you have never had any problems with setting offset to 0, > even for AIX, but the facts speak for themselves. > > If you are using AIX and Logical Volume Manager then it is necessary to use > offset 4Kbytes (1 page) to avoid this problem. > > Malcolm Weallans

A recommendation I was given was to use offset of 4 when using raw devices as the LVM uses the 1st 4k block for it's own information. I've never experienced it as a problem but generally speaking I'd say better safe than sorry...... Regards Colin There are 10 types of people in the world, those that understand binary and those that don't >From: "Ferro" <rbferro@gmail.com> >To: informix-list@iiug.org >Subject: Re: Use of offset 0 with AIX >Date: 8 Nov 2006 10:27:07 -0800 > >Hi Malcolm > >Would be good if you tell us the vresion of AIX and IDS of your >customer. >I was using AIX 4.3.3 and 5.2 with LV (raw devices) for chunks and >setting 0 to offset and I had never problems even when I restored >instances. > >Best regards. Ferronato > >malcolm weallans escreveu: > > > I have just been through a DR situation on one of our customer sites >that > > had offset 0 for some chunks. And the recovery process couldn't rebuild > > some of the chunks correctly. And the ones it had problems with were >those > > that had offset set to 0. In those cases the Logical Volume Manager > > complained that the Logical Volume Control Block was corrupted. >Fortunately > > this was on their test server. > > > > I know many of you have never had any problems with setting offset to 0, > > even for AIX, but the facts speak for themselves. > > > > If you are using AIX and Logical Volume Manager then it is necessary to >use > > offset 4Kbytes (1 page) to avoid this problem. > > > > Malcolm Weallans > >_______________________________________________ >Informix-list mailing list >Informix-list@iiug.org >http://www.iiug.org/mailman/listinfo/informix-list _________________________________________________________________ The new Windows Live Toolbar helps you guard against viruses http://toolbar.live.com/?mkt=en-gb