FreeBSD NFS server not responding to TCP SYN packets from Linux/SunOS clients

[Eric Anderson]

rick at snowhite.cis.uoguelph.ca wrote:
[..snip..]
> rick
> ps: It would be nice if someone with the right expertise could explore
>     other things in TCP specifically for NFS. For example, I don't see
>     why a retransmit timeout should go above about 100msec, since net
>     delays are well below that level, even half way around the world
>     these days. Having said that, I don't know enough about TCP retransmit
>     to say that one second retry intervals aren't correct?

Wouldn't this be a problem for a server under high disk load?  If the 
disks are very very busy, and clients are requesting stat's on files, 
etc, then the server would be waiting on disk, and the time could be way 
more than 100ms, even more than 1s.  Of course, this would be a slow 
server because of the load, however it does occur, and so lowering it to 
100msec might be too aggresive.  If you have many many clients, all 
attempting lots of NFS activity, during times of load you could make the 
server even more overloaded with all the retransmits, right?

Eric



-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
Anything that works is better than anything that doesn't.
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