Well, most people don't bother or even know why they would unless jockying servers. Most will just pop in _one_ hard disk, install linux, and call it a day celebrating the imminent death of windoze. Until it fails, they scratch their head, cry, and get another _one_, not understanding two redundant disks are just a possibly easy to setup/use and would have saved the hassle. I've been playing with raids since the 90's where slowaris taught me partitioning strategies. I forced myself to learn/use software raid once linux became viable for me full-time with ubuntu. Once I found the Ubuntu Alt cd circa 6.06 had recipies for raid/lvm already, it was a no-brainer. I use the alt disk exclusively for desktop to layer file systems, mostly because I : 1) need redundancy (md), 2) need crypto (luks, work laptop roams with me, or not), and 3) need versatility (lvm, partitioning extends for those "wow, win7 is really a pig wanting 25g for a silly vm, good thing I left free space on the vg!" moments). You have to use that really ugly and scary ncurses menu on Alt installs, but after dozens of installs I can fly with it much more efficiently than the full desktop, with way more rich disk features. I'm surprised more linux users don't pay their desktops respect they would a server with raid. It's almost as painful to toss a disk without redundancy in a desktop as it is a production server, in may ways more. MDadm has been more of a pain in recent years, but all in all it's saved me at least 3 times on personal systems over the years from a total loss, even though recovery isn't always so straight forward. Time well spent to learn - good subject for a hackfest. -mb On 03/26/2012 11:45 PM, ChasM Marshall wrote: > Wow! > > This is the first I've seen here that ANYONE is using a seperate /boot > partition. > > I've been using one since about 2.2 kernels. > I started out using 50Mb but, with Ubuntu and GRUB 2.0 > it needs around 300Mb to 500Mb. A Fedora 15 install didn't > complain using a little as 150Mb. The minimum is for my > Windows "ntldr" which requires only 50Mb. > > I've never needed LVMs or software raids for my desktop. > As I understand it, they are not involved during boot, but are > a requirement to access the newer GRUB config scripts in Ubuntu. > Use a live boot disc, as Stephen says, to be sure they are accessable. > Most of my (single-user) boxes have three to seven OSes to boot from. > All within a less than 100Gb hard drive. I'm using Grub Legacy. > > If your Centos server is a large system, you may rather try this on a > seperate hardware test machine, for safety. I've seen trouble from the > Ubuntu GRUB scripts. Specifically, their "os_prober" has problems > identifying other bootable kernels and systems when generating > the new Ubuntu boot menu. > > Another problem is that Ubuntu is capable of GPT or MBR hard drives. > MBR is the classic Master Boot Record. > GPT is newer, larger, and demands specific hardware abilities. > I've seen Win 7 using GPT, so caveat emptor. > > (-: Chas.M. :-) > > ------------------------------------------------------------------------ > Date: Wed, 21 Mar 2012 20:11:34 -0700 > Subject: Re: Going from Centos 6 to Ubuntu Server > From: nadimhoque@gmail.com > To: plug-discuss@lists.plug.phoenix.az.us > > Well with my setup I do have the boot partition separate from the LVM > and the raid is pure software as far as I know. I was just asking if it > was safe to do so. Unfortunately the boot partition is a bit on the > smaller size at 100mb so I can easily fit around 2 kernels. I guess the > other reason I am thinking to switch is because with Ubuntu, they have a > predictable release schedule and with 12.04 LTS around the corner, I can > get a server OS that is "stable" and up to date. I know I can compile > from source all of the packages I have, like the the kernel and the > software for the LAMP stack that I am also running. > > I also like the fact for the Ubuntu implementation of Samba; I can use > the the system username and password instead of first creating a user on > the system and again as a samba user. Other than that I do like Centos > right now. Thanks for your help. > > On Wed, Mar 21, 2012 at 7:21 PM, Michael Butash > wrote: > > Should be able to - depends how you're partitioned. > > I'm assuming your raid0 is done with mdadm and not fake-raid based. > > As long as your boot partition (non-lvm) is large enough to support > enough kernels, you should be able to install over the system lv's > you don't want, and not touch the ones that you do. Probably just > create new lv's assuming you have the space for new root, usr, var, > whatever you want. I usually create home without a separate > partition, leaving alone the existing home, and simply mount the > /home lv after reinstall "just in case". > > Note I've had some weirdness with ubuntu/mdadm depending what > version mdadm metadata it was built with. In 11.04 I had to build > md's specifically to use 0.90 metadata to work fully (i.e. reboot > without having to busybox assemble md manually), 11.10 and higher I > had to build the raid specifically with the current version > (default) to work. > > I layered luks/lvm/ext4 atop this too, never did figure out exactly > which was borking it, but the metadata was the trick for me. It also > could have been related to my ssd alignment partitioning that always > gave me grief with low-level fs. > > -mb > > > > On 03/21/2012 03:19 PM, Stephen wrote: > > if it boots up and sees the LVM then you should be able to customer > partition and configure without reformatting. > > you can look and see a fair amount without even writing changes > to the disk. > > However i would still make a backup. > > On Wed, Mar 21, 2012 at 1:55 PM, Nadim > Hoque> wrote: > > I currently have Centos 6 installed with software raid 0 > with LVM. I was > wondering if it is possible to install Ubuntu server 10.04 > with those > settings without data loss and that the current raid/lvm > will stay in tact. > So far in my experience I should be able to do this, but I > just wanted your > input on the matter. I might switch to ubuntu server for the > vast number of > packages in the default repos and when I used it before I > really liked it (I > love how the default repos have what I want, and ufw is nice > as well). > > -- > Nadim Hoque > Undergraduate Intern > ASU Advanced Computing Center > Cell: 480-518-6235 > > ------------------------------__--------------------- > PLUG-discuss mailing list - > PLUG-discuss@lists.plug.__phoenix.az.us > > To subscribe, unsubscribe, or to change your mail settings: > http://lists.PLUG.phoenix.az.__us/mailman/listinfo/plug-__discuss > > > > > > ------------------------------__--------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.plug.__phoenix.az.us > > To subscribe, unsubscribe, or to change your mail settings: > http://lists.PLUG.phoenix.az.__us/mailman/listinfo/plug-__discuss > > > > > > -- > Nadim Hoque > Undergraduate Intern > ASU Advanced Computing Center > Cell: 480-518-6235 > > --------------------------------------------------- PLUG-discuss mailing > list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, > or to change your mail settings: > http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss > > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us > To subscribe, unsubscribe, or to change your mail settings: > http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss