Solved: Question on 802.1q and PIX

jamey · ‎11-24-2003

I was looking at this document about PIX and 802.1q VLAN trunking:

http://www.cisco.com/univercd/cc/td/doc/product/iaabu/pix/pix_sw/v_63/config/bafwcfg.htm#1140519

In this example there is a server in VLAN1. The physical interface of the pix is put in VLAN2 and a virtual interface is created for VLAN3. How would the server in VLAN1 get to the devices in the other VLANs in this case? Am I missing something?

-TIA

scoclayton · ‎11-24-2003

Hi,

I think I understand your confusion. It looks to me like there is an error in Figure 2-9. The hosts above the distribution layer switch should be in VLAN 2 and VLAN 3 rather than VLAN 1 and VLAN 2. As you know, the default VLAN on any Cisco switch is VLAN 1 and we suggest that you not use this VLAN for anything in a production network. If you change the hosts in the figure to VLAN 2 and VLAN 3, does this example make more sense? In other words, look at the info and think about it as two seperate interfaces. Let me know if this is still not clear.

Scott

PS - I will open a bug to fix this example.

View solution in original post

scoclayton · ‎11-24-2003

Hi,

I think I understand your confusion. It looks to me like there is an error in Figure 2-9. The hosts above the distribution layer switch should be in VLAN 2 and VLAN 3 rather than VLAN 1 and VLAN 2. As you know, the default VLAN on any Cisco switch is VLAN 1 and we suggest that you not use this VLAN for anything in a production network. If you change the hosts in the figure to VLAN 2 and VLAN 3, does this example make more sense? In other words, look at the info and think about it as two seperate interfaces. Let me know if this is still not clear.

Scott

PS - I will open a bug to fix this example.

jamey · ‎11-25-2003

Makes sense to me...Thanks!

d-g-c · ‎11-25-2003

On a similar subject what is the correct command line syntax for creating an 802.1q virtual interface on a PIX physical interface?

I'm struggling with the syntax show in the manual.

Peter.

scoclayton · ‎11-25-2003

Are you asking for something other than:

[no] interface hardware_id vlan_id [logical | physical] [shutdown]

Example:

interface ethernet0 vlan3 logical

Let me know if this is not what you are looking for.

Scott

d-g-c · ‎11-26-2003

thanks, my mistake I was trying to use

interface ethernet0 vlan 3 logical

vmolinaro · ‎11-26-2003

Good job Scott. I had the same problem understanding this figure and the VLAN config. Clears it up for me too.

Vito