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Posted

Hi All,

 

Before I have to make some calls, does anybody have any insight into what has happened here?

 

A teacher came to me and said that his students couldn't save to their home drive, I looked at the PC and there were no network drives, but also there was no school desktop wallpaper so I knew it had not picked up all of the profile. No biggie, it happens occaisionaly, the students couldn't save their work, but neither could I as it appears it had picked up enough of the profile to lock it all down... :confused:

 

Anyway, I shut it down and thought no more of it. However, in the ICT room the other day the teacher said that this particular PC still did not pick up the wallpaper (which is what I said he should check for). That set alarm bells ringing, so I sat down and tried to log on as admin and I couldn't. So I logged on to the local machine as admin and found all sorts of strange things going on (in the attached screenshot).

 

DHCP is being controlled by CISCO router/switch that are externally managed and DNS is managed from our two DC servers.

 

I have flicked through the DNS records and cannot find any record of this PC.

The IP address and DEFAULT GATEWAY come from a VLAN given to a neighbouring school who we share a connection with and the IP given for the DNS server in the screenshot, comes from a page that says "The intranet site is not set up yet".... WTF! The PC's are set to obtain both automatically. I cannot remote into it and now I cannot join to a domain (as I thought dropping off and reconnecting would help).

 

I do not even know where to start fixing this, I hope EDUGEEK has someone that can give me some simple step-by-step instructions on what to look for?!

 

Kol.

 

DNS_ERROR_CENSORED.jpg

Posted
Are your DC servers externally managed? The DNS addresses being given out by DHCP should be that of your DC's. If it's not then that's where the problem is. The DNS address in the screenshot certainly looks outside the scope of your IP range. Is there a reason why DHCP is being run from the Cisco router intstead of one of the DC's? Have you checked the settings other PC's are getting, are they getting the same DNS server from DHCP? If so you need to contact whoever externally manages the Cisco box and get them to correct the DNS settings it's reporting with DHCP.
Posted (edited)
Try changing the port in the switch the PC is patched into, the way I'm reading the post is that the PC is in the wrong VLAN. Worth a shot. Edited by HallX
Posted

Ok can't get physical access to the PC at the moment. DHCP is managed by the CISCO router\switch set-up and is not configured by our DC server but as far as I know DNS is run from our DC server. I'm not sure why, I inherited this set-up and the CISCO side is managed.

 

I can't get into to the room to plug the PC into a different port either, but I will give it a shot once I can. All 29 other PC's get the correct IP and DNS and they are all plugged into the same switch/patch panel. Yup totally in the wrong VLAN, but I honestly don't know how that could have happened.

 

Kol.

Posted

I'd agree with HallX, this does sound like a VLAN issue. This would explain why it doesn't show up in DNS or why it cannot obtain an IP address from DHCP.

 

I'd bet even if you configured a static IP, it still wouldn't work which would back up the VLAN theory!

 

Edit: A quick fix would be to re-patch it at switch level into a port you know works.

Posted
Is there a reason why DHCP is being run from the Cisco router intstead of one of the DC's?

 

I can only think that DHCP is run from the CISCO router/switch rather than DC is because of the various VLAN's we have set-up and that we share a connection with a neighbouring school. I'm quite glad I didn't have to set all that up with scopes and exclusions!

 

There is no manual IP set, it is configured to obatain via DHCP.

 

I still cannot understand why this port on the switch would randomly lose its configuration. However over the half-term the power was apparently shut off...

 

Kol.

Posted
Is there a reason why DHCP is being run from the Cisco router intstead of one of the DC's?

 

I can only think that DHCP is run from the CISCO router/switch rather than DC is because of the various VLAN's we have set-up and that we share a connection with a neighbouring school. I'm quite glad I didn't have to set all that up with scopes and exclusions!

 

There is no manual IP set, it is configured to obatain via DHCP.

 

I still cannot understand why this port on the switch would randomly lose its configuration. However over the half-term the power was apparently shut off...

 

Kol.

 

If you do configure a static IP (temporarily), this would prove if it's a VLAN issue or not. It is quite easy to mis-configure VLANs, especially if it's done remotely.

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