[K12OSN] OT: still have sluggish system

[Les Mikesell]

On Wed, 2006-09-13 at 01:28, dahopkins at comcast.net wrote:

> > Then reboot the machine(s) and go to the closet and unplug the client
> >connection to the switch. See if the load spikes on the server. If it's
> >OK, start plugging in segments to see if the switch is bogging down and
> >if so, on what segment. Keep an eye on the server load.
> 
> It is some form of broadcast traffic on the system.  Since I have cups running, and also 2 Windows TS, and samba, I guess this might be expected, just seems somewhat more than typical.  

There are about 40,000 windows viruses that can do this.  Or
someone plugging a loop into your switches in a way that
spanning tree doesn't catch.  I'd suspect something like
that first and start pulling wires out of the problem switch
until it stops, then follow the wire.  A good diagnostic
tool is a laptop running ethereal (windows or linux). If
your switch isn't manged so you can monitor traffic by
plugging into another port and bridging it, you can
pull each wire showing activity and plug it into a small
hub with the laptop. 

> I have noticed with ntop that a alot of thin clients show up as multihomed.  Not sure why since they only have one entry in the dhcp-k12ltsp.conf file.   Also, some of them have rather high values for NFS(???),  but this is not specified anywhere in the lts.conf file.  The only other change was using glx, I have disabled that as well.

Ntop can get confused if it can't keep up.  Don't trust it too
much.  And it keeps historical data so it may have seen the
same terminal with different dhcp addresses.   If you
restart ntop you should get a better view of current activity
but you may not see the problem from that connection
anyway.

What happens if you disconnect the 'outside' interface
of the k12 server?  Does the client side work OK then?

> So ... I am left with no idea what is going on. 

If you are doing LDAP authentication and/or NFS home dirs, those
are probably having trouble with lost packets on your
main net and it isn't going to work until you fix the
network issue or at least isolate your boxes from it.

-- 
  Les Mikesell
   les at futuresource.com