NFS (and NIS) client causes server to semi-hang

NFS (and NIS) client causes server to semi-hang

[Seb James]

Hello,

I've come across a rather worrying problem.

I have a small network of computers, sitting behind a adsl modem/router.
The internal ip domain is hypercube, I have also called the yp domain
hypercube as it is the identical set of machines.

The server is:

circle.hypercube 

nis server, nfs fileserver, dhcp server, firewall. 

I know it shouldn't be a firewall at the same time as all those other
functions, but it is for now as I want to use it as a stand alone
machine if nothing else is running. It's running redhat 7.2, fully
updated with security patches. Kernel version is 2.4.20-18.7 (a redhat
precompiled kernel).

The two clients are:

darius:    desktop machine running fully updated redhat 9.0 installation
herodotus: a laptop also with updated redhat 9.0.

Herodotus is set up to mount /home and a directory called /data from
circle, with the following lines in /etc/fstab:

circle:/data            /data                   nfs     defaults        0 0
circle:/home		/home			nfs	defaults	0 0

It is also set up as an nis client, with the following in /etc/yp.conf

domain hypercube server circle.hypercube

And it works just fine, so I believe the server is correctly set up.

Darius has the same set-up as herodotus, but......

Neither nfs nor ypbind function.

Trying to mount a volume:

[root@darius /]# mount /data/
pmap_getmaps rpc problem: RPC: Timed out
mount: RPC: Port mapper failure - RPC: Timed out
[root@darius /]#

NB: a portmapper is running on both darius and circle (and herodotus,
too).

Trying to start ypbind:

[root@darius /]# service ypbind start
Setting NIS domain name hypercube:             [  OK  ]
Binding to the NIS domain:                     [  OK  ]
Listening for and NIS domain server........    [FAILED]
[root@darius /]#


Now, when I try to do *either* of these, the server starts to play up.
It begins to timeout on almost anything network or authentication
related. For example, to bring up a new terminal window in X takes at
least a minute and to then access a website using, say lynx, takes a
similar time. I'm confused as to why both ypbind and mounting a volume
on the server should be able to cause this denial of service.

Does anyone have any ideas?

Also, is there a suitable NIS related list to post this message to, as I
think it's relevant for that, too.

best regards,

Seb James.

-- 
Seb James <seb@peak.uklinux.net>



-------------------------------------------------------
This SF.NET email is sponsored by: eBay
Great deals on office technology -- on eBay now! Click here:
http://adfarm.mediaplex.com/ad/ck/711-11697-6916-5
_______________________________________________
NFS maillist  -  NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs

Re: NFS (and NIS) client causes server to semi-hang

[Seb James]

On Thu, 2003-06-12 at 11:17, Seb James wrote:
> Hello,
> 
> I've come across a rather worrying problem.

[ snip ]

> Does anyone have any ideas?
> 
> Also, is there a suitable NIS related list to post this message to, as I
> think it's relevant for that, too.


Fixed: darius was not listed in the /etc/hosts.allow file. However, it
doesn't seem right that such a problem should lead to the server
freezing up in the way that it did.

Cheers,

Seb.

-- 
Seb James <seb@peak.uklinux.net>



-------------------------------------------------------
This SF.NET email is sponsored by: eBay
Great deals on office technology -- on eBay now! Click here:
http://adfarm.mediaplex.com/ad/ck/711-11697-6916-5
_______________________________________________
NFS maillist  -  NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs