HUGE NETWORK PROBLEM

[RichB]

Right where in some serious trouble here!!! Yesterday I came in at dinner time after been in a car crash to this:

Full network down - Reason loop back BUT NOW

*no access to my documents
* no access to sims
* cannot save
*when opening my documents a list from AD comes down to them in folders of different year groups? when they click on them the pc crashes
*No mapped drives....

This is me out of my confort zone.... ALOT any help would be great!

[jamesreedersmith]

Have "ALL" the servers and switches had a reboot yet?

[DAZZD88]

Rebooting the switches should give you pklenty of time to have a look at event logs on them and determine roughly where your loopback is.

[ICT_GUY]

Check that DHCP is working. Shut-down servers, restart switches bring it all back up on-line and see where you are.

[djm968]

After the reboot, I would try and isolate each network segment, by pulling all the fibre and Cat5 links to the edge cab and switches and just leave your servers connected. Then start reconnecting the edge until you are sure you are stable.

[RichB]

Sorry no ive found the loopback and now have all these problems? there is 100% no switches/loop back problem now!

[RichB]

And no shared areas.....

[strawberry]

Check your fileservers and domain controllers, Prehaps reboot them?

[laserblazer]

If you ping the server from a workstation, how long does the reply take? I had a similar problem and it was a duff D-Link 5 port switch.

[djm968]

Check event logs for DHCP and DNS errors on the Server(s) and the test Workstation. Also (I know you have probably already done) but ensure you reboot the workstation you are using to test with.

[RichB]

pings from work stations are instant!

[dwhyte85]

Hi RichB,

Have you rebooted/restarted the servers/services sequentially? E.g, firstly reboot PDC, DHCP, DNS, Exchange, FS?

If you've got no shares is the server service started?


We had something similar to this, and I was absolutely certain there was no loopback, it turned out that one cabinet had 1 switch that had not been rebooted and this was causing the issue.

We also had an issue with a netgear 5 port that had just died and caused masses of problems.


EDIT: But our pings were not instant, sounds like services on the servers - best to check eventlog

[djm968]

Can you ping the Server(s) NetBios and DNS names?

[strawberry]

pings from work stations are instant!

So its not likely a network problem, Check the event logs on the servers, check the services, check the resources being used. Disconnect the servers from the network, reboot them, then reconnect.

[robk]

If needed turn EVERYTHING off, turn on Switch attached to servers, and then servers. Do they ping ok etc. then add machines back in block at a time. Sounds like a crashed switch or server with crashed network stack from the loop back.