Unanswered Question
Jul 26th, 2007

I'm using a 3560 switch. The switch is set up with 10 vlans. Devices on vlan 3,4 and 5 are talking to each other through intervaln routing (done by the swtich itself). I'm able to ping devices on vlan 5 from my unit on vlan 4 and data are being routed without any problem.

What i'm not able to do is telneting those devices from my unit which is again on vlan 4.

i know that enabling DHCP between vlans needs the command ip helper-address, wondering if i need to do something similar to enable telnet between vlans.

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
purohit_810 Thu, 07/26/2007 - 12:01

You can assign access list permit on 23 port.

assign that on vlan.

Please try it.



Jon Marshall Thu, 07/26/2007 - 12:06


As previous poster suggested do you have any access-lists on your vlan interfaces ?.

If not there should be nothing stopping you telnetting to the devices. You certainly don't have to do anything on the switch. The devices youa re trying to telnet to - what are they.

Can you telnet from one device to another within the same vlan ?


valides007 Thu, 07/26/2007 - 12:22

i didn't set up any access-lists on the switch. I'm able to telnet the device to another withing the same vlan.

Jon Marshall Thu, 07/26/2007 - 13:34


What actually happens when you try to telnet.

Does it just hang or do you get a "connection refused" message ?


Tony.henry Thu, 07/26/2007 - 13:10


There is no need to setup helper addresses to get telnet working.

Indeed it sounds like routing is working correctly, as your able to ping from vlan4 to vlan5 without issue. I'd suggest that it's time to break out the ethereal or equivalent packagage and look at the devices to ensure that not only are they listening for telnet connections, but they are responding appropriately.


Danilo Dy Thu, 07/26/2007 - 19:40


You mentioned that devices in vlan3, vlan4, and vlan5 are talking to each other. From vlan4 you can ping devices in vlan5 and data being routed without problem. On top of that, there is no ACL.

What are those devices you are trying to connect via TELNET?

If those devices are Servers(2003)/Workstations(XP/Vista), check if TELNET service is running, if they have built-in firewalls, you need to permit incoming connection to TELNET service.

If those devices are Routers/Switches, you need to configure local authentication in VTY as you cannot TELNET to them with default VTY config out of the box.



EPHRAIM MANI Sat, 07/28/2007 - 02:24


as suggested jon.marshall you are able to telnet with in the lan/VLAN.

My query

1. Is this a new setup with 3560 swith with 10 VLANS

2. Was this working earlier in the current setup with 10 VLANS and intervlan routing.

4 What are those devices to which u r telneting.

5 I suspect somet type of access restriction is at place on those device/application which alows telnetting from its own network but not from the remote network i;e VLAN3,VLAN5 etc except for VLAN4 which is in same network.

kindly check the device/application running telnet service

Kindly rate all the post if its helpful.


This Discussion