Re: [CentOS] LVM question
On 01/17/2012 11:40 AM, Steve Thompson wrote: > on LVM is quite safe as long as it is below 2GB It's not possible put /boot on LVM when you working with GRUB. Grub works with 2 stages: 1º - MBR ( Master Boot Record ) , with instruction to access the partition where store kernel , initrd and grub.conf 2º - Reads the partition indicated on 1º stage (MBR), to read grub.conf with all instruction to boot the OS. Now the question why we cannot use /boot on LVM. LVM is a Logical Volume Manager, GRUB no have support yet to read LVM. You'll see this LVM structure after the kernel boot and load the LVM modules. You could see what filesystems are support by Grub access your /boot after installation, looking into /boot/grub. Only Grub version 2 could access partitions /boot with LVM. ( I find this information now ) - You'll not have problem using SWAP on LVM, but we need think about all situations. If you running some software that use too much SWAP area, recommend you put your SWAP on the firsts primary partition on your disk, because there are area more fast I/O. If you want know more about that looking for about ZCAV. (This is applicable to electrical mechanical disk, no Solid State Disks,SSD). Let's think you need more SWAP space, but your using SWAP on LVM, you could create a new LVM and add to SWAP area. swapon -s (you could see information how many swap partition or files you have and how much is the use of them) best regards, --aslan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Errors in /var/spool/mail/root
On 01/17/2012 11:38 AM, Jonathan Vomacka wrote: > CentOS Experts, > > I am receiving the following in /var/spool/mail/root. I cleaned out the > file and then rebooted and the same errors came back. Is it possible to > analyze the data and advise if there is an issue with my system? This is > a completely fresh install. > > From u...@localhost.srv.net Tue Jan 17 08:11:56 2012 > Return-Path: > X-Original-To: root@localhost > Delivered-To: r...@localhost.srv.net > Received: by fst.srv.net (Postfix, from userid 0) > id 6F02E2A0078; Tue, 17 Jan 2012 08:11:56 -0500 (EST) > Date: Tue, 17 Jan 2012 08:11:56 -0500 > From: u...@localhost.srv.net > To: r...@localhost.srv.net > Subject: [abrt] full crash report > Message-ID: <4f15739c.MHhrv8Xn0YkMj8Xp%user@localhost> > User-Agent: Heirloom mailx 12.4 7/29/08 > MIME-Version: 1.0 > Content-Type: text/plain; charset=us-ascii > Content-Transfer-Encoding: 7bit > > Duplicate check > = > > > Common information > = > architecture > - > x86_64 > > package > - > kernel > > kernel > - > 2.6.32-220.2.1.el6.x86_64 > > > > Additional information > = > kernel_tainted_long > - > Taint on warning. > > kernel_tainted > - > 512 > > backtrace > - > WARNING: at arch/x86/kernel/cpu/mtrr/generic.c:467 > generic_get_mtrr+0x11e/0x140() (Not tainted) > Hardware name: empty > mtrr: your BIOS has set up an incorrect mask, fixing it up. > Modules linked in: > Pid: 0, comm: swapper Not tainted 2.6.32-220.2.1.el6.x86_64 #1 > Call Trace: > [] ? warn_slowpath_common+0x87/0xc0 > [] ? warn_slowpath_fmt+0x46/0x50 > [] ? generic_get_mtrr+0x11e/0x140 > [] ? mtrr_cleanup+0x8c/0x3fd > [] ? get_mtrr_state+0x2ec/0x2fb > [] ? mtrr_bp_init+0x1ab/0x1d2 > [] ? setup_arch+0x4b8/0xaea > [] ? printk+0x41/0x44 > [] ? start_kernel+0xdc/0x430 > [] ? x86_64_start_reservations+0x125/0x129 > [] ? x86_64_start_kernel+0xfa/0x109 > > > time > - > 1326805905 > > component > - > kernel > > hostname > - > fst.srv.net > > reason > - > WARNING: at arch/x86/kernel/cpu/mtrr/generic.c:467 > generic_get_mtrr+0x11e/0x140() (Not tainted) > > cmdline > - > ro root=/dev/mapper/VolGroup00-root rd_NO_LUKS LANG=en_US.UTF-8 > rd_MD_UUID=435d8e67:5dceefb3:85c46cf3:9f6cb0df rd_LVM_LV=VolGroup00/swap > SYSFONT=latarcyrheb-sun16 rhgb crashkernel=129M@0M quiet > rd_LVM_LV=VolGroup00/root KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM > > kernel_tainted_short > - > -W > > analyzer > - > Kerneloops > > os_release > - > CentOS release 6.2 (Final) > ___ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos Hi, After reboot check your kernel messages, running on terminal this command 'dmesg'. Check if this information appears to you, if yes could be a bug or hardware problem. best regards --aslan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] anyone doing automatic yum updates via yum-updatesd on production servers?
On 01/17/2012 02:30 PM, P J wrote: > I've read that it's not recommended to automatically apply updates via > yum-updated on production servers, but I keep encountering servers that > have this enabled. > > Are any of you doing automatic yum updates on production servers in CentOS > 5 via yum-updatesd? Have you experienced any negative side effects? > > The only thing I can think of is if say a client had a custom version of > PHP installed that was not properly excluded in yum and then it was over > written. > Unless I'm missing something else that could go horribly wrong. > > Any feedback is appreciated. (if this question has already been asked my > apologies, searching the archive didn't find what I was looking for) > > Thanks, > > -PJ > ___ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos Hi PJ, Good practices is don't update any package on server directly without test before. It's because some update may not full compatible with your configuration. I do the update first on test server to ensure that update will not break my system. I didn't update directly without test this new package before, so I never get troubles on updates to my servers. If you have many server with same package to update, first try one in Testing (of Dev) Environment, if no have problems, send your servers update the packages. best regrads --aslan best regards. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Wrong PV UUID
On 01/19/2012 07:56 AM, Muhammad Panji wrote: > Dear All, > I have one VG with one LV inside consist of four disk (and four PV) somehow > the UUID is changed. I try to restore with the last known good > configuration and use > > pvcreate --uuid xxx --restorefile xxx > > but I think when I first time do it I did use wrong UUID for two device. > but haven't only using command above and haven't used vgcfgrestore. After > carefully read the configuration, using hdparm to know device serial number > I think I have assign the right UUID for each device. I succesfully use > vgcfgrestore, but I cannot mount the device (unknown filesystem, bad > superblock, etc). My questions are, is my first attempt to assigning > (wrong) UUID make all the LVM corrupt? I see that all LE and PE is still > there, the VG and LV size is right but still I cannot mount the volume. Is > this just a bad filesystem or the data really gone? Thank you. > Regards, > > > > > > Hi, Why theses 4 PV lost UUID? Have some hardware change ? It's not common this happen, just lost LVM Meta Data on PV, something wrong happened. The problem is reconstruct meta information about Mapping of blocks ( PE ) to LV, if your LV used blocks mapped across the four disk, I recommend you running check file system.. e2fsck to repair. Well if e2fsck don't solve this problem, it time find out the last backup. :( best regards, --aslan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
