[TriLUG] FreeNAS vs DIY

[Jimmy Dorff]

On 9/16/13 4:05 PM, Bill Farrow wrote:
> Any volunteers to run a hackday on setting up and maintaining a ZFS or
> BTRFS home file server ? Maybe a demo of FreeNAS ? This could
> culminate in a TriLUG talk ?

Don't know about a "hack day".. but I'll write about ZFS.

I run several ZFS file servers for my department. Most are using hybrid 
storage pools (SSDs as read and write cache). In general these aren't 
"home" systems, unless you want a 36 drive 4U rack system at home :)

One is running FreeBSD and the others are running OpenIndiana. Mostly 
these are NFSv4 servers and I've found the illumos NFS server to work 
very well. I use amanda for backup. NFS clients are all Linux.

Some other departments here are using the Nexenta commercial ZFS 
appliance as well.

Key points to look for:
* drive failure handling. I think this is a weak area in non-illumos 
based ZFS. I know FreeNAS/FreeBSD are improving this area. Things like 
turning on the correct drive failure light and handling hot swap. Even 
for a home system, taking out the wrong drive is never fun.

* for hybrid storage pools, simply acquiring enterprise SLC SSDs is 
difficult and very expensive. For a "home" box, a cheaper ssd is 
probably fine... but that would depend on what you are doing at home!

* (performance) I've found that illumos does a very good job of 
reporting device error statistics. I often find on a large array one 
drive is "working" but has more errors than the others and is slowing 
everything down. Replacing that one drive can greatly speed up the array.

* hardware selection is very important.. both for good drivers and a 
good layout / architecture. Experts say sata port multipliers are evil 
and sas is good. I've found people at pogolinux and ixsystems are very 
good storage systems vendors and they both support open source.


Cheers,
Jimmy