On Sunday 12 February 2006 13:38, Alexander Skwar <[EMAIL PROTECTED]> wrote about 'Re: [gentoo-user] Max Number of Partitions': > Boyd Stephen Smith Jr. wrote: > > On Sunday 12 February 2006 06:45, Jarry <[EMAIL PROTECTED]> wrote about > > 'Re: > > > > [gentoo-user] Max Number of Partitions': > >> There are some limitations concerning lvm. I remember it is not > >> recommended to use it for <swap>, root and /boot (and probably > >> some more)... > > > > Some distros (kubuntu, I believe) use LVM swap by default if you use > > LVM. While this could theoretically cause a problem, > > Could it? How and why?
I'm thinking of some obsure case where the code or data needed to read swap has been swapped out. > > Putting swap on LVM does have the distinct advantage of allowing swap > > to be resized when you add or remove (!) ram -- I like swap to be ~2x > > ram. > > Well, it's very easy to create a swap file. As that's no longer > a disadvantage performancewise, what you stated is not an > argument for LVM. I don't like swap files cluttering up my filesystem. :) > > Root on LVM is entirely possible. I've run that way since I initially > > installed linux (well, initially, this time around). You do have to > > create either an initrd or an initramfs that loads any needed modules > > that are not built in and activates the lvm logical volumes; genkernel > > can do this for you on gentoo. > > That's right. But if you also wish to use suspend-to-disk (swsusp > or http://suspend2.net/ ; suspend2-sources), you won't be able > to use a genkernel created initrd. I roll my own initrd / initramfs anyway, it's not really that hard just a bit tedious. > > /hda1 -- /boot as big as you need it. I use 1G, but that's overkill > > for most people. > > That's gross overkill :) I do very fine with only ~64 MB. I have 4G of RAM. I have an rescue initrd on boot that contains a gentoo install with all my recovery tools, basically a livecd. /boot is not full, but 1G is a nice round number. > > You can than create a volume group with your single physical volume > > and begin cutting logical volumes out of it. The default limit to the > > number of logical volumes in a volume group is 255. When you need > > more storage you can add another hard drive, create a physical volume > > out of the whole drive (no need to partition), extend your volume > > group, and start growing your logical volumes across the new drive > > I'd *STRONGLY* urge to *NOT* do this, if we're talking about > normal consumer hard disks and especially if no backups are > done. What happens, if disk1 in a 2 disk VG goes broke? Um, activate the vg in partial mode and lvols on the good disk will still be accessible -- I think even writable, but I could be wrong on that point. I'm not sure if that's in the standard lvm startup scripts on gentoo, but my initrd includes vgscan -P; vgchange -Pay. > Nah, too dangerous for me. I use multiple Volume Groups. Then you can't have a lv that's bigger than a single pv or migrate data between pvs (to switch them out or w/e) using pvmove. You are seriously crippling the usefulness of lvm if you always use a 1 pv = 1 vg rule. -- Boyd Stephen Smith Jr. [EMAIL PROTECTED] ICQ: 514984 YM/AIM: DaTwinkDaddy -- gentoo-user@gentoo.org mailing list
