IT Experts - Help needed!

[Keydogg]

Hi everyone,

We had a lightening strike down the road from us the other day and the surge has hurt a few bits and pieces, such as an alarm panel, network switch (cheap one), wireless AP (again, cheap), printer.

Now, it's royally fucked with our network. Although we've had a switch and AP go down, everything else seems ok. Our Cisco router works fine, HP managed switch, zyxel firewall and other stuff also.

The thing I'm having trouble with is certain network ports in the walls, and by this I mean the main router is hooked up to a 6-gang network faceplate when then feeds through the building to various locations, which come out at single network face-plates.

Now, the trouble is that I seem to not be able to gain network access from 2 out of 5 of these locations, but this just seems odd. (One of these says it's connected but then I can't ping anything, and DHCP won't assign). Surely the network cable in the walls can't be fried as the switches at either end are fine, and I can't see how a surge would go through a switch down a cable and fry the cable.

If anyone has any experience please give me your opinion as I'm pulling my hair out!

 

[ThomasBrentnall]

Try a cable tester on the structured cable to ensure all pairs are fine.
Also try restarting the switch

 

[Don]

Restart media converter (if you have one) and then restart switch etc (make sure you do it in order they come into building so first in is first to restart...then when you restart the final piece, everything else should find the piece before it.

 

[Keydogg]

Thanks lads. Don, I will try that specific restarting method and see what happens, never tried it in that order yet but it's a good idea!

I'm also off to get a LAN tester today as I could do with one to help me out.

 

[ThomasBrentnall]

Thanks lads. Don, I will try that specific restarting method and see what happens, never tried it in that order yet but it's a good idea!

I'm also off to get a LAN tester today as I could do with one to help me out.

Keep us posted!

 

[Darren S]

Technically (though unlikely) it could fry one or more of the wires in the structured cabling. Don't forget, the wires are really quite thin and would have made a perfect transport medium for lightening to travel through, if accessible to the storm itself.

If you're running 10/100 speeds over CAT5 however, it's unlikely to be this (unless you're really unlucky) as those speeds only require 4 of the 8 wires in the cable. If you were running full gigabit, they need all 8 and would arguably be far more susceptible to a single wire failure.

I'd definitely recommend what Thomas said - cable testers are literally a few quid these days anyway.

D.

 

[paddyyyyy]

I have to agree, pick up a cable tester for a few quid. No point testing hardware if your cables are fried.

 

[Keydogg]

Technically (though unlikely) it could fry one or more of the wires in the structured cabling. Don't forget, the wires are really quite thin and would have made a perfect transport medium for lightening to travel through, if accessible to the storm itself.

If you're running 10/100 speeds over CAT5 however, it's unlikely to be this (unless you're really unlucky) as those speeds only require 4 of the 8 wires in the cable. If you were running full gigabit, they need all 8 and would arguably be far more susceptible to a single wire failure.

I'd definitely recommend what Thomas said - cable testers are literally a few quid these days anyway.

D.

Never thought of this actually. I'll try 10/100 mode and see if that changes anything!

 

[The Fatty]

It could just be that these ports were active at the time of strike and the switch is damaged on these ports.

 

[KDF]

It could just be that these ports were active at the time of strike and the switch is damaged on these ports.

More likely than the cables that a few of your switch ports got fried.. seen this happen before. But as suggested a cable test should be carried out anyway.

 

[Keydogg]

Looks like you were right guys, cabling all tested fine. Now I'm just struggling with VLANs, had it set up fine on the Cisco Router > HP Switch but I can't get it to work with TP Link Router > HP Switch.

On my Cisco I just created a 2nd VLAN, tagged it to a port 2. Tried this on TP Link below:

Then, on the HP Switch add a second VLAN for port 1 (coming from router) and port 2 (going to VLAN 2 machines), and have VLAN one on that switch on Port 1 and all other ports apart from 2:

Can anyone see where I'm going wrong? Ports 3-8 on the HP switch all have access to VLAN 1 (as they should) but port 2 doesn't have access to anything, including the internet (but it should have the internet!).

 

[Keydogg]

Got it sorted in the end. I needed to create a VLAN that encompassed the three separate VLANs that I needed, then viola!

 

[BruceTea]

Isn't that a trunk?