<quote who="[EMAIL PROTECTED]">
> 1) Why do you need a ram disk if raid1 and ext3 are not modules, but
> actually compiled into the kernel?
You don't. :)
> 2) If you have a separate ext2 partition for /boot, do the modules have
> to be there too? (Or are you expected to use an initrd then?)
No on both counts.
> 3) What is /initrd for, anyway? Why does that empty directory exist at
> all?
It's there if you want to move the initrd's root somewhere after you mount
the new (real) root filesystem. Generally you just unmount it anyway.
> 4) Where did Red Hat get there jbd.o module from? My 2.4.17 kernel
> source doesn't have that as an option. It's either built in, or not
> there at all.
No idea what Red Hat do with their kernels.
> > Mirroring root is OK. You just need to put /boot somewhere else.
>
> It still seems strange that using RAID to mirror root is a bad idea,
> since it seems to me that raid1 was designed for mirroring file systems
> in the first place (especially root)! And it seems even stranger to
> recommend that mirroring it manually, on the other hand, is good.
Not really; this is software RAID, and you're competing with a different
class of problems to hardware RAID. Especially when you start bringing
modules loaded from "a filesystem" (could be initrd, could be root) into the
equation.
Herbert is right, but I'm slightly more conservative, so I keep a minimal
root/boot partition, and have everything elsewhere. Basically, my data
matters, my software doesn't. I can rebuild or mirror it easily enough.
> I'd honestly like to know more details about why some people recommend
> against using raid on the root file system.
What does it gain you? What pain do you have to go through to use it
(barring nice RAID installers like Red Hat's)? What pain do you have to go
through to recover or fix it? Why expend these resources on something far
less critical (and simpler to replace) than your data?
> Do I need to have /lib/modules on the same /boot partition? (If I
> don't, aren't I going to have just the same problem with finding the
> modules before the filesystem is mounted?)
No. /boot holds your kernels. If those kernels have RAID built in, or
include initrd images, they will let you use RAID on any subsequent mounts.
I always set my software RAID paritions up to autodetect, and have RAID
stuff built into the kernel. So much hassle avoided.
> Fortunately, juggling kernel configs is trivial with the Tk/Tcl mods to
> the xconfig's scripts that I mailed a while back.
"cp <blah> .config" works pretty well too. :)
G'luck!
- Jeff
--
"Evil will always triumph over good, because good is dumb." - Dark
Helmet, Spaceballs
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