From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx09.extmail.prod.ext.phx2.redhat.com [10.5.110.13]) by int-mx03.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id n9UJkMXe020157 for ; Fri, 30 Oct 2009 15:46:22 -0400 Received: from ps536.phatservers.com (ps536.phatservers.com [216.17.105.202]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n9UJk4G5019446 for ; Fri, 30 Oct 2009 15:46:04 -0400 Received: from r74-192-24-94.bcstcmta01.clsttx.tl.dh.suddenlink.net ([74.192.24.94] helo=raydesk1.bettercgi.com) by ps536.phatservers.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.66) (envelope-from ) id 1N3xQC-00046Z-4B for linux-lvm@redhat.com; Fri, 30 Oct 2009 12:46:04 -0700 Date: Fri, 30 Oct 2009 14:46:03 -0500 From: Ray Morris Subject: Re: [linux-lvm] Best Practices deploying LVM In-Reply-To: <868096450910300152s271d34dcl74980fff211d15b4@mail.gmail.com> (from jockah@gmail.com on Fri Oct 30 03:52:43 2009) Message-Id: <1256931963.28005.3@raydesk1.bettercgi.com> MIME-Version: 1.0 Content-Disposition: inline Content-Transfer-Encoding: 8bit Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="utf-8"; delsp="Yes"; format="Flowed" To: LVM general discussion and development With your way, you can add a new 2GB disk and use half of it for /home, half for /opt, if you wish. You can also leave some of it unused and expand any LV in the future as needed. That's one important reason why most people use voluem groups as groups - contianing several volumes. Does your colleague know of ANY advantage to creating a bunch of different groups? If not, your way wins - it has advantages over his way, and his way has no advantage. > we have to discard different kinds of hard disk > because they're exactly the same I have no idea what this is supposed to mean. Different kinds of hard disk are exactly the same? If this is supposed to mean "we are not able to use different types of drives for different partitions", I can understand that. However, for what purpose would you use different types of disks? Perhaps he wants a fast disk for one partition, and a large, cheap disk for another partition? If you use two cheap disks in a striped LV it's going to be faster AND cheaper than the "fast drive" option. MAYBE if you were going to use a super fast RAID array of SSD drives for some small amount of data, but not if we're talking standard magnetic hard drives. > a lot of servers running under VMware. This client > have a lot of problems with the storage, because they > never have enough space so when they have to allocate > disk in servers, they add small virtual hard disks > with, for example, 5 or 10GB. lvextend. Ours resize automatically on the fly, using a cron job that checks to see if any virtual servers need more space. > discarding concept things like a volume group was designed > to be a group, because we're looking for good reasons "Concept reasons", like using the tool designed for the job, may be the very best reasons because that one reason actually covers the hundred reasons that don't come to mind immediately. You don't know what issues you'll run into next week or next month, but you can bet you won't be the first one - other people will have had the same issues, and will use the standard tools for the standard purposes to solve that problem. Better for you if you can use the same solutions. Also, there are certain features and optimizations you don't know about, but you'll gain from those grouping features if you use groups as groups. No one knows about the features and optimizations that will be added next year, but if you use the tools the way they were designed you'll benefit from future enhancements that allow you to better use them for their purposes. -- Ray Morris support@bettercgi.com Strongbox - The next generation in site security: http://www.bettercgi.com/strongbox/ Throttlebox - Intelligent Bandwidth Control http://www.bettercgi.com/throttlebox/ Strongbox / Throttlebox affiliate program: http://www.bettercgi.com/affiliates/user/register.php On 10/30/2009 03:52:43 AM, Abraham P�rez wrote: > Thanks for the instant answers! > > Well... I'll try to explain myself better. I'm working in a client > who have > a lot of servers running under VMware. This client have a lot of > problems > with the storage, because they never have enough space so when they > have to > allocate disk in servers, they add small virtual hard disks with, for > example, 5 or 10GB. > > Then for the OS installation, we follow the basic schema based on disk > partitions (/dev/sda1 pointing to / with ext3, /dev/sda2 pointing to > /home > and so on) and for the applications data, we use VG and LV pointing > to /opt > > The client have some applications who need a lot of mountpoints, so my > colleague adds 1-3 LV per VG (aproximated) and I only create only one > VG and > inside it, different LVs. With this infrastructure, we have to > discard > different kinds of hard disk because they're exactly the same... and > we have > that doubt: what schema is better and why, discarding concept things > like a > volume group was designed to be a group, because we're looking for > good > reasons based in performance of future actions, it's not important... > or am > I mistaken??? > > I don't know if I explained myself very well, so thanks all anyway! > > Regards, > Abraham P�rez > > 2009/10/30 > > > Ray Morris [support@bettercgi.com] wrote: > > > I don't know about a whitepaper, but I can address > > > your example. > > > > > > > he makes one volume group for each logical volume (more or less) > > > > > > If each one has one volume, that's not exactly a volume > > > GROUP, is it? If groups and volumes are basically synomous, > > > he gives up all the benfits of groups. In fact, he gives > > > up most of the benefits of logical volumes, since each PV > > > has to be in one group, and each VG is one LV, you're left > > > with one LV per PV - might as well just use partitions > > > directly. > > > > I agree, you lose some flexibility but it has some advantage > compared to > > plain partitions without LVM. E.g. he can make a file system larger > than > > any disk with multiple disks in the above LVM (one LV per VG) > > configuration. There are other advantages. I am not sure the > reason for > > making only one LV per VG though! > > > > Thanks, Malahal. > > > > _______________________________________________ > > linux-lvm mailing list > > linux-lvm@redhat.com > > https://www.redhat.com/mailman/listinfo/linux-lvm > > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > > > ------quoted attachment------ > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/