UFS2 with SAN

[Eric Anderson]

On 02/10/07 00:54, Chris Haulmark wrote:
> 
>> -----Original Message-----
>> From: Eric Anderson [mailto:anderson at freebsd.org]
>> Sent: Saturday, February 10, 2007 12:48 AM
>> To: Chris Haulmark
>> Cc: freebsd-fs at freebsd.org
>> Subject: Re: UFS2 with SAN
>>
>> On 02/09/07 19:30, Chris Haulmark wrote:
>>> Hello,
>>>
>>> I am looking into setting up a SAN with several web servers that
>>> will be clustered.  It would be a FC network using Qlogic cards
>>> in each of those FreeBSD web servers.  It would be about 5+
>>> of those web servers.
>>>
>>> I want to have the capability to share the same web data across
>>> those web servers.  I have scorched the entire mailing list and
>>> found that there were some work on GFS porting over to FreeBSD.
>>> It seems like that it is just all talk and if I am wrong, could
>>> you have my head turned over to where I can find out how to enable
>>> GFS on those FreeBSD systems.
>> GFS on FreeBSD is indeed dead.  Not enough people stepped up to help
>> port it.
> 
> I really feared to hear that!
> 
>>> If GFS is out of question, which file system am I recommendeded
>>> to attempt to use for this SAN setup?
>> NFS.
>>
>>> My first thought to use UFS2 and attempt is to allow only one web
>>> server to have a write/read access while the reminder would be
>>> read only access. That should prevent from lockings that is similar
>>> on NFS/NAS.
>> This will result it the read/write system seeing the data ok, and the
>> rest getting corrupt data without knowing it, and probably crashing.
>> UFS2 is not cluster aware.  You could mount all the hosts read only,
>> and
>> then update the mount point on one to rw, makes changes, then back to
>> ro, then unmount/remount on the other boxes.
> 
> That's my original idea if I do not have anything else better to go
> with.
> 
>> That's all still a kludge to simulate what NFS will do for you.  Why
>> won't NFS work for you?
> 
> I have a client who wants to go from NAS to a true SAN solution with
> full
> fibre channel network.  I would hate to lose the opportunity for this
> client
> to continue using FreeBSD as the choice of OS for his web servers.
> Currently,
> his set up is using NAS with NFS.  He complains of locking files that
> occurs
> too often.
> 
> I had hoped to find more better solution and make this client much more
> happier
> with all the FreeBSD support that can be provided.


Well, I'm not sure what issues they had, but have had fantastic success 
with NFS and FreeBSD.  FreeBSD with the right hardware and tweaks can 
make some NetApp boxes look weak. *cough* WAFL *cough*


>> I agree that it would be fantastic to have a clustered file system for
>> FreeBSD, and I've done lot's of hunting and nagging vendors to support
>> it - but it's just not there.
> 
> We should get few bandwagons and get in circle.  It could be likely that
> I could
> provide access for the developers to test and get whatever file system
> and other
> necessaries needed to be working. :)


The problem isn't the environment or hardware, it's developers skilled 
to do the work.  They're all either in NDA's, off writing something 
else, or just too busy to provide any amount of input.

Eric