Building Out XenServer 6.5 with USB Boot and Software RAID 10

Romo

We don't need to install mdadm, its there already

scottalanmiller

@Romo said:

I got the uuid using this:

madadm --detail /dev/md10 | grep UUID

Thanks.

scottalanmiller

@Romo said:

I got the uuid using this:

madadm --detail /dev/md10 | grep UUID

What is the raw output of that command? Did you need to clean it up? I want this scripted, not manual, if possible.

brianlittlejohn

i'm going to have to try this out, i have an old dell with FAKERAID.

Romo

This is the output @scottalanmiller just have to replace : with -

UUID : fba59a9c:7e6db5a2:d21e4034:3b415cfd

mlnews

i'm going to have to try this out, i have an old dell with FAKERAID.

You can do it anywhere. No FakeRAID needed since the whole point is to bypass it. Works equally well where there is no FakeRAID too.

Romo

echo "modprobe raid10" > /etc/sysconfig/modules/raid.modules
modprobe raid10
chmod a+x /etc/sysconfig/modules/raid.modules

mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[a-d]

Loading the modules to kernel need to go before creating the md device

scottalanmiller

@romo can you confirm if this command works?

madadm --detail /dev/md10 | grep UUID | cut -d' ' -f3

Romo

I got a blank output after fixing madadm to mdadm

scottalanmiller

It worked on the output that you gave to me.

scottalanmiller

See what -f2 does.

scottalanmiller

I refreshed the OP with the latest revisions.

Romo

DustinB3403

Romo can you confirm if SDA is the USB drive?

we need to confirm that it's not attempting to be added to the Array with

mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[a-d]

Romo

Yes in my setup sda simulates to be the usb, thats why the array starts with sdb

DustinB3403

OK so scott change the script to start at sd[b-e]

Romo

I believe it should be in this order:

modprobe raid10
chmod a+x /etc/sysconfig/modules/raid.modules
mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[a-d]
cat /proc/mdstat

DustinB3403

You mean

mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[b-e]

Need to be very certain we aren't attempting to overwrite the OS USB

Romo

We should also add that he needs to finish the array building before trying to add the filesystem

watch cat /proc/mdstat to see it build in real time

And also @scottalanmiller i only get mkfs.cramfs mkfs.ext2 and mkfs.ext3 as available fs by default

Romo

@Romo

You mean
mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[b-e]
Need to be very certain we aren't attempting to overwrite the OS USB

Yes, sorry I just copied the OP to show the order. The array needs to start with sdb, sda is the usb