VLAN & Connecting 3560 to 2950

[phillips_eei]

This is a first time try for me.

I'm trying to connect the main switch here (3560) to two 2950s via fiber on SFP ports. The connection lights are green at both ends (3560 and 2950 ends) but I can't ping.

The 3560 switch has 3 VLANS configured: 10, 12 and 15. I'm only dealing with VLAN 10 which has a subnet of 172.16.1.* and an IP of 172.16.1.1.

I tried to assign SFP ports on the 3560 49 and 50 to be considered part of VLAN 10 but when I look at the port status page it says they are "trunk".

The one 2950 I want to communicate to is IP address 172.16.1.20. The 2950 does not have VLAN configured - but I thought I wouldn't need to do that. There's a device connected to the 2950 with an IP address of 172.16.1.21 which we need to communicate with.

Thanks.

[mohammedmahmoud]

Hi,

When connecting 2 cisco switches, they need to be connected via a trunk connection, and all the VLANs should be defined on both switches.

HTH, please do rate all helpful replies,

Mohammed Mahmoud.

[phillips_eei]

Thanks for the response.

So, on the 2950 end I need to define a VLAN. Does it have to have a VLAN ID of 10 to match my 3560? Or can I just leave VLAN ID at 1?

I will be trying possible solutions in the morning.

Thanks.

[phillips_eei]

Also - can trunk connections be considered part of a VLAN?

Thanks.

[mohammedmahmoud]

Hi,

No, when i said that when connecting 2 cisco switches, they need to be connected via a trunk connection, and all the VLANs should be defined on both switches.

I meant that if you are using for example VLAN 10 and 13, you need to define both VLANs on both switches.

As for the trunk connection (between 2 trunk ports between to cisco switches) - the trunk is a link that can move traffic from all VLANs between 2 Cisco switches, meaning that if a frame from VLAN 10 needs to go from switch 1 to switch 2, it can go over the trunk, and also if another frame belonging to VLAN 13 it can also use the trunk to go from switch1 to switch2, the trunk port is not bind to a VLAN, it can have all VLANs flowing over it to go from a switch to another.

NOTE: Any switch port can be configured as a trunk port (having all VLANs flowing over it - Used to connect 2 switches) or as an ordinary access port in only 1 VLAN (used to connect to client workstations).

HTH, i hope that i've been informative, please do rate all helpful replies,

Mohammed Mahmoud.

[chris.lepa]

Hi,

If you are only dealing with VLAN 10 on the 2950, that link doesn't have to be configured as a trunk. You can configure the uplink port and all other ports on the 2950 as a VLAN 10 access port (as well as the port it's connected to on the 3560).

That's just an option, but should you need more than VLAN 10 on that 2950, trunking is required.

-Chris