ZFS - Boot and special device on same SSD mirror

[Klug]

Hello.

I'm sure I read it but I can't find the thread anymore.

I'll be building a new PBS server soon.
Main storage will be 12 rotating disks in ZRAID3 and I've learnt the hard way (>48hours garbage collector) I need a special device for metadata.

I'd like to setup a ZRAID1 mirror of two datacenter SSD of 960 GB.
The idea is to cut this volume in half, 60 GB of boot and 900 GB of special device.

Will this work?
Can I do this during guided the setup of PBS?

 

[ph0x]

It runs the same way here. Just set the hdsize in the installer accordingly and the rest of your disks will stay free for further partitions which can then also be used as a special device, for example.

 

[Klug]

So you created the mirror zpool with the installer, then set a tiny partition for boot et voilà?

 

[ph0x]

In the installer you click on "options", there you can set hdsize which will be the size of your root partition.
Afterwards you can create more partitions with the tool of your choice.

 

[Klug]

Perfect, thank you.

 

[Klug]

I eventually did it on a server yesterday.
I created a RAID1 of two SSD in the PBS setup, then in "Advanced option" used only 30 GB for PBS.

Then once PBS was installed, using fdisk I created a new partition on each SSD.
Then added these partition as a special mirror to the existing pool (exported/imported from FreeNAS).

Seems to work.

 

[benoitc]

does it makes sense though to have the system disk shared with the special disk on the same SSDs? What is the possible issue?