High Availability NFS server configuration....

jason andrade jason at rtfmconsult.com
Thu Mar 6 14:06:00 CST 2003

On Thu, 6 Mar 2003, Mansell, Gary wrote:

> I have a Dell PE2650 with two internal Qlogic qla2300 HBA's that attach via two seperate fibre cables directly into an EMC FC4500 disk storage array configured with 1TB of RAID 5 storage. The machine is an NFS /SMB server to the whole company. The storage array has two SP controlers installed, currently I am only using one of the HBA's to communicate to one of the FC4500 SP's. The other controller and SP is there so that I can manually reconfigure it into action should the other channel fail. Obviously this will involve downtime to reconfigure the system.

quite a nice config.  and you must be glad you have the 4500 instead of the 4700 :-)

> I would like to make this solution more slick so that it does not require any / as much operator error in time of failure. I was originally intending to purchase the Linux Powerpath software just released by EMC to Load balance the data to and from the FC4500 across the two HBA cards and also to provide a dynamic failover capability should one of the HBA's or fibre cables fail. I have heard that this may not work with my FC4500 because it is not intelligent like the FC4700?

if you can go back through the list archives i think (might be wrong) that powerpath
(3.0.2?) for linux should support the 4500/4700/cx200/cx400 etc boxes, i.e everything
that is currently sold by dell.   it doesn't seem to support the older 650/660F stuff.

> Another solution that has been suggested to me is to use Linux's LVM and it's md multipathing capability that comes with the O/S coupled with the Qlogic v6.04 (failover capable) driver for my FCAL cards. This should (for no extra cost :-) ) give me the resilience that I desire.
> Does anyone have any experience of the above configuration?

i don't have personal experience but anecdotal evidence from other people indicates
that this would be "bleeding edge" in terms of a tested/well deployed solution.

in particular, LVM1 is shortly to be superseded by LVM2 which is apparently a much
better piece of software and i know a lot of people are waiting for that (myself
included :-)

> Where can I find out more about LVM and multipathing, I have tried googling for it but have not found any Howto's etc?

search inside the LDP, e.g http://ldp.planetmirror.com (or your nearest mirror) and
it should come up with the LVM/software raid HOWTO.

> How robust is this solution (is it bleeding edge or well tested) - my server is critical to the company?

are you asking us if it is critical or not ? :-)

if you want support and a tested config then possibly the vendor solution is going to be
better for you as from the above it appears you have a pretty standard deployment.

there are a couple of EMC/dellEMC guys/gals on this list who could answer this question
if you go back through the list though.



More information about the Linux-PowerEdge mailing list