From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Andreas Dilger Message-Id: <200103291910.f2TJAAl09275@webber.adilger.int> Subject: Re: [linux-lvm] safe to ru-run vgscan after mounting LV root? In-Reply-To: from Jay Sissom at "Mar 29, 2001 09:46:01 am" Date: Thu, 29 Mar 2001 12:10:10 -0700 (MST) Sender: linux-lvm-admin@sistina.com Errors-To: linux-lvm-admin@sistina.com Reply-To: linux-lvm@sistina.com List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-lvm@sistina.com Jay Sissom writes: > Nope, I am running kernel 2.4.2 with the beta6 patch and the beta6 > utilities. OK, that's a bad sign. > This started after I resized a LV. The answer from this list was, "don't > run vgscan". Now people on the list say you can run it as many times as > you like. If I run it once, all my LV's are gone. I'd like to figure out > what the problem is, but don't know where to start looking. You _should_ be able to re-run vgscan, but in most cases (as you have seen) it is not _necessary_ to do so. In any case, how to track down the problem - run "vgscan -v -d" and start going through the output with a fine-tooth comb. Basically, at some point you will start getting errors, and that is what is bad (it is OK to get error codes in a few places, like when checking if a partition/disk has an LVM header on it). For a VG to be operative, you need all of the PVs in it to be OK. This seems to be a common source of problems. I have a modified pv_read_all_pv() and pv_read_all_pv_of_vg() which is a lot better in terms of reporting why a PV was discarded from the PV list. This may make finding the source of the problem easier (even obvious ;-). You can find it in an email to the lvm-devel mailing list dated March 15 "Re: [lvm-devel] Extent list sorting considered buggy". Cheers, Andreas -- Andreas Dilger \ "If a man ate a pound of pasta and a pound of antipasto, \ would they cancel out, leaving him still hungry?" http://www-mddsp.enel.ucalgary.ca/People/adilger/ -- Dogbert