[wplug] NFS Server Tuning

[Michael Skowvron]

Matthew T. Engel wrote:
> My question: How can I tune the server to all clients can mount share,
> or any suggestions to other problems I might have?

Matt,

As far as I know, there is no software limitation imposed by NFS that 
would prevent you from serving your 40 clients. Your system could easily 
allow 400 clients to mount your share, because keeping track of a 
client's mount is very trivial. I would have to suspect that there is 
something else going on.

Is the server on the same subnet as the clients, or are there any 
routers in your configuration? If so, is anything doing NAT translation? 
Are there any iptables rules configured on the server?

What kind of an error do you get when reach the mount limit? Does both 
the client and the server report some type of error, or just one of them?

In your research you came across recommendataions on the number of nfsd 
processes to run. This has nothing to do with your current problem. The 
recommendations are based upon how individual NFS transactions are 
handled and how many cpu cycles they consume. Without going into too 
much detail, the goal is to have enough daemons so that requests aren't 
dropped, but don't have so many that some are always idle. The idle 
daemons actually waste cpu cycles.

Once you get past this mount problem, your biggest issue may be 
performance. I don't know what kind of disks or I/O system you have on 
your server, but they are going to have a huge impact on the performance 
and even the stability of your lab. Do you have any idea how much data 
the clients are expected to be accessing?

Michael