[BBLISA] SunFire 4500: Linux + ZFS/FUSE ?

[John P. Rouillard]

In message <4FF7103C.8030004 at crystal.harvard.edu>,
Ian Stokes-Rees writes:
>I just had a conversation with a colleague about turning a 20+ disk IBM 
>GPFS system into a ZFS-based file server (GPFS no longer licensed), so 
>this comment:
>
>On 7/6/12 10:20 AM, Edward Ned Harvey wrote:
>> What are your purposes? Have you considered btrfs? Personally, I have 
>> found btrfs to be more buggy and riddled with landmines than zfs. I'm 
>> waiting another year before revisiting btrfs again. I like zfs, but 
>> only in a *fairly* supported configuration.
>made me wonder "what is a 'supported configuration'?" -- What other good 
>options are there for 20-40 disks on two shelves?  Put them into 
>separate RAID volumes in blocks of 4-8 disks?

At $WORK we have our 4500's configured with 4 11 disk raidz2 pools and
4 spares in the chassis. It takes a long time to resilver (a week or
more) and scrubbing takes a while as well.

Also we have an issue with the 4500's where a drive can die and the
hardware/software won't ignore it. This leads the to the box going
offline until you physically pull the offending drive. You can usually
tell what drive is toast from the errors on the console or
/var/adm/messages, but zpool status just hangs.

I don't know if that is a side effect of having so many disks in each
pool or not, but I have been told it is an issue with the 4500
hardware.

So I would choose smaller raid volumes if I was setting this up on new
hardware. You lose disk space (you lose 2 disks of capacity for every
raidz2 array), but I (from anecdotal evidence with smaller arrays)
expect the slowdowns we have seen due to scrubbing and resilver times
would be less if the arrays were smaller.

--
				-- rouilj
John Rouillard
===========================================================================
My employers don't acknowledge my existence much less my opinions.