[SATLUG] First question - RAID5 quit working
satlug at net153.net
Sun Aug 16 15:24:29 CDT 2009
David Labens wrote:
> First, I apologize that I've been part of the group online since DECEMBER, and this is my first attempt to contact. Life has been busy, but I'm not making excuses.
> In December, I built a home server with an Asus motherboard & AMD 6400 processor & 4 gb RAM. It's got an 80 gb HDD that is used exclusively for the OS (Linux Ubuntu 8.10 Server, running mostly headless unless boot-up visual is required, like right now), and 4 250 gb HDDs that are s/w configured as RAID5.
> Everything has worked exceptionally well (built in December, not a glitch until 2 weeks ago), then, suddenly, I started getting errors trying to rename a folder. I did a shut-down and reboot, and the RAID5 is no longer mounting.
> Here's some current diagnostics:
> root at RCH-SERVER:/boot/grub# cat /proc/mdstat
> Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
> md0 : inactive sde1(S) sdc1(S) sdb1(S) sda1(S)
> 976783360 blocks super 1.0
> unused devices: <none>
> And, I've tried:
> root at RCH-SERVER:/home/admiral# mdadm --assemble --scan
> mdadm: /dev/md/0 assembled from 2 drives - not enough to start the array.
> I KNOW that two brand new Western Digital HDDs did not go bad simultaneously, and really doubt that either of them went bad. I read that it's a known problem that they get busied out by the OS, so I'm trying thinking this is the issue.
> UNFORTUNATELY, I put off buying 1 tb drives for backup, and all our recipes, family pics, real estate, music, etc. is on there. I have just received and installed one on in my Win XP Pro box, so I'm ready to do a first backup IMMEDIATELY upon getting the RAID5 array back working.
> Any suggestions? Any thoughts? We're on a limited budget, but I'd be willing to pay someone who can make it work!
> David Labens
> San Antonio, TX
Oh yuck. You are on pins and needles! If there is important data on here
then the first thing that I would do is pray! Then spend the next hour
(or maybe 2) reading the manual page: http://man-wiki.net/index.php/8:mdadm
You are going to have to force it to assemble. Pretty much the thing as
Do not make the mistake like this guy and think that restarting the
machine is going to magically fix anything. In fact, I would not
restart the machine again until the array is fully rebuilt and synced.
So yes, step one, see if forcing will work:
mdadm --assemble --scan -f
Also always make sure that email alerts are set up with mdadm. To check
that email alerts are working do mdadm --monitor --scan --test. This
will send an email to the root account on the server. And on my server,
all of root's emails get sent to my main email account so I can keep an
eye on things...
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