Limited connectivity on some machines- DNS?

[marsdenprimary]

Hi,

 

For some bizarre reason I have suddenly started receiving 'limited or no connectivity' issues on a number of machines in our ICT suite. We use software called 'AB Tutor' which is classroom management software and I have noticed that some of the machines aren't being picked up and other are displaying the wrong 'name' (e.g. IT001 is actually IT004) etc...

 

If I login and renew the ip- all is well again.

 

I have also noticed that all the ports on our switch are periodically flashing at the same time, all together intermittently. Could this be connected?

[djm968]

Sounds like a loop somewhere.

[marsdenprimary]

Hmmm...would that only affect machines in our ICT suite though? The other pc's on the network seem to be ok...

[djm968]

That would depend on how the ICT switch and the other switches in your network infrastructure are configured. When STP (Spanning Tree Protocol) is configured correctly, the loop should be isolated just to the affected switch. I have also seen a dodgy network card create network loop type symptoms also.

[marsdenprimary]

Interesting. It appears to have started when I installed our new Brother network printer. Think that could affect it?

[djm968]

Sounds like it may well be the culprit. Have a look at the menu on the device and check that its not trying to do any broadcasts (network discovery type stuff). I had a MF printing device try and do a similar thing.

[djm968]

Did you install the Brother web BRAdmin server software? a quick google suggests this does some network device discovery stuff also.

 

http://welcome.solutions.brother.com/bsc/public_s/id/webbradmin/en/web_bradmin_agent.html

Edited July 19, 2010 by djm968
URL Added

[laserblazer]

Unplug the printer and see if that fixes it.