I want to use two ssd's in a raid 0 configuration as a cache drive.

 

I created a RAID0 array in the bios of my unraid server, however unraid does not seem to see that - it still sees the individual disks.   Is this expected?

5 minutes ago, dvd.collector said:

it still sees the individual disks.   Is this expected?

Yes, Unraid doesn't support most RAID controllers, and definitely not "fake" RAID like Intel RST or similar, you can use a btrfs pool and change the profile to raid0:

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480421

 

Thanks for the quick reply.

 

I don't suppose I have much choice, but is a btrfs raid 0 pool as fast as I would expect (e.g nearly double the speed of a single ssd)?

 

Lee.

OK, I removed the raid 0 from the bios and added both ssd's as cache drives.  Now I see the attached error message.

 

Clicking format does nothing.

 

Yes, performs similar to other software/fakeraid raid implementations.

clear both devices with:

 

blkdiscard /dev/sdX

 

OK, so I stopped the array, ran the blkdiscard command on both disks, restarted array but see the same error message.

 

Should I have removed them as cache drives first?  I'll try that now anyway.

You'll still need to format them, if format fails after wiping post the diagnostics.

Attached Diagnostics.

tower-diagnostics-20181108-1929.zip

 

Can see this in the logs, is it trying to format one drive as XFS?

 

Nov 8 19:26:34 Tower emhttpd: shcmd (1000): /sbin/wipefs -a /dev/sde1

Nov 8 19:26:34 Tower emhttpd: shcmd (1001): mkfs.xfs -m crc=1,finobt=1 -f /dev/sde1

Edited November 8, 20187 yr by dvd.collector

4 minutes ago, dvd.collector said:

is it trying to format one drive as XFS?

Yep, don't know why, never seen this before but it looks like a bug.

 

With the array stopped click on cache and change filesytem to btrfs.

OK so when I click on Cache, I can change that to btrfs.   When I click on cache2, it says "unknown" in partition format.

 

Went ahead and changed Cache to btrfs anyway then clicked format.

 

It looks like this worked (see screenshot).

 

Now just need to change to raid 0 i guess.

Edited November 8, 20187 yr by dvd.collector

Conversion to raid0 appears to have worked:

 

Many thanks for your help!

Hello

 

How did you change it to raid0 please ?

6 minutes ago, RealIPSec said:

How did you change it to raid0 please ?

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480421