DrayTek UK Users' Community Forum

Help, Advice and Solutions from DrayTek Users

Network problem

More
05 Nov 2019 18:19 #1 by haywardi
Network problem was created by haywardi
Ok, I will start by saying I am not sure this is the right place for this, but I have a really odd network problem I have not seen before so hoping someone can help me.

First a quick overview of my network.

1. 2860 acting as internet router, DHCP server and set up with 4VLANS
2. 2 Managed switches (lets call them SW-A and SW-B).
3. Three Win 10 Pc's (lets call them PC-A, PC-B, PC-C) All PC's on the same subnet and Vlan (internally 192.168.1.x)
4. Each of the PC's are getting the correct DHCP assigned IP address.
5. PC-A & PC-C are on switch SW-A
6. PC-B is on switch SW-B

My problem is this

PC-A can Ping PC-C
PC-B can ping PC-C
PC-A CANNOT Ping PC-B
PC-B CANNOT ping PC-A

For the life of me, I can't see how the switches are making any difference, BUT I can't rule it out!

Has anyone got any ideas?
I

Iain

Please Log in or Create an account to join the conversation.

  • hornbyp
  • User
  • User
More
05 Nov 2019 18:38 #2 by hornbyp
Replied by hornbyp on topic Re: Network problem
If you plug PC-B into SW-A, can it ping PC-A?
If you leave PC-B plugged into SW-B, but directly connect SW-A and SW-B (removing SW-B's link to the Vigor), does it work?

Please Log in or Create an account to join the conversation.

More
05 Nov 2019 18:52 #3 by haywardi
Replied by haywardi on topic Re: Network problem
Unfortunately the distance between PC-B and SW-A is to great to just plug PC-B it into SW-A; but I may just pick it up and move it, so not impossible.

I should have added:
SW-A & SW-B are trunked with tagged data between them.
SW-B has not direct connection to the vigor, it routes through SW-A

Iain

Iain

Please Log in or Create an account to join the conversation.

  • hornbyp
  • User
  • User
More
05 Nov 2019 19:59 #4 by hornbyp
Replied by hornbyp on topic Re: Network problem

haywardi wrote: SW-B has not direct connection to the vigor, it routes through SW-A



So - other than to issue an IP address, the Vigor 2860 isn't actually involved...probably more of a 'tagging' issue on either Switch or PC ?

Assuming this the configuration:-
Code:
+-------------+ | | | Vigor2860 | | | +-------------+ | | | +-------------+ | | | SW-A | | | +-------------+ | | | +----+ | +----+ |PC-A| | |PC-C| +----+ | +----+ | | +-------------+ | | | SW-B | | | +-------------+ | +----+ |PC-B| +----+

Please Log in or Create an account to join the conversation.

More
05 Nov 2019 20:09 #5 by haywardi
Replied by haywardi on topic Re: Network problem
Yep your chart is right and yes the 2860 isn't involved in routing as this is handled by the switches.

If it's a tagging issues then the PC's wouldn't be getting the right IP addess (each Vlan has a different IP address) AND crucially, if it were a tagging issue why can eveything see PC-C? This is my dilemma!

Iain

Iain

Please Log in or Create an account to join the conversation.

More
05 Nov 2019 21:45 #6 by x64
Replied by x64 on topic Re: Network problem
Windows firewall????

Please Log in or Create an account to join the conversation.