3Com 3300 1

[RobWB]

Hi All,

I am using a 3Com 3300 (software v2.7) switch with 802.1q connection to a Cisco router. Everything is working fine, but I cannot telnet to the switch for management purposes because the workstations are not members of VLAN 1 (they are members of the relevant 802.1q'd VLAN). Is there a way around this or do machines that require telnet access to the switch have to be VLAN 1 members ?

Thanks,
Rob.

 

[ADB100]

You need to create a sub-interface on the Cisco router in VLAN #1, make sure you can route packets to the VLAN (relevent gateways, static or dynamic routes etc), and that should be it.

Andy

 

[RobWB]

Thanks for your help Andy.

I did think about a new sub interface for supporting VLAN 1 on the switch but wasn't sure if Cisco had some internal use for it.

When the sub interface is created to support VLAN 1, will it need an ip address of its own so that any attempt to telnet to the switch from a machine on the switch will go via the router and locate VLAN 1. ?

Also will the switch IP address need to be within the subnet allocated to VLAN 1 for management to work ?

Thanks for any help.

Cheers,
Rob.

 

[ADB100]

Yes. You will need to create a new subnet/network for VLAN-1 and place the IP addresses for the 3300 and the Cisco sub-interface in this network/subnet (3300 default gateway to the Cisco address).
How have you configured the 802.1q trunk with regards to VLAN-1? Is VLAN-1 tagged or is it the 'UnTagged VLAN'? If its untagged then either configure the IP address for the Cisco Router on the Major Interface (Interface FastEthernet0/0) OR create a sub-interface and set the encapsulation as the Native VLAN:

Interface FastEthernet0/0.1
encapsulation dot1q 1 native

Either way will work.

If VLAN-1 is tagged use:

Interface FastEthernet0/0.1
encapsulation dot1q 1

Good luck

Andy

 

[RobWB]

Andy,

Thanks for the help.

At the moment, I have five sub interfaces on the router 192 - 196 which correspond to existing 802.1q vlan names on the switch. At present, VLAN 1 only exists on ports 23 and 24 (which I considered as spare, and for management).

From what I now understand, by adding a tagged VLAN 1 to port 1 on the switch (where the router connects). Then creating another sub interface (FastEthernet0/0.1) on the router with a new subnet and the switch IP within that subnet. This will then mean that all requests to telnet to the switch (from wherever they are located), will arrive at the switch via the router interface onto a port that has VLAN 1 presence and therefore managability.

Hope I have that right ?

Thanks,
Rob.

 

[ADB100]

Rob you are correct, config would look like:

interface fastethernet0/0
!
interface fastethernet0/0.1
description VLAN #1
ip address 192.168.1.254 255.255.255.0
encapsulation dot1q 1
!
interface fastethernet0/0.10
description VLAN #10
ip address 192.168.10.254 255.255.255.0
encapsulation dot1q 10
!
interface fastethernet0/0.20
description VLAN #20
ip address 192.168.20.254 255.255.255.0
encapsulation dot1q 20
!

etc


Andy

 

[RobWB]

Andy,

Thanks very much for your time and help.

Regards,
Rob.