UNSOLVED

Bubbagump210

updated

14 years ago

0

4599

October 10th, 2012 12:00

VLAN confusion with LAGs

I currently have 3 5548s in 3 separate closets. As we established in an earlier post, I need to run a LAG between Closet 1 and 2 and then a separate LAG between closet 2 and 3.

Now comes the difficulty. I need to have 2 VLANs. VLAN 1 will handle our internal LAN traffic. VLAN 2 will handle traffic for a guest wifi network and will haul back to the internet demarc. Each switch will have one port that goes to a wifi AP. The wifi AP tags packets so that SSID 1 can be on VLAN 1 and SSID 2 can be on VLAN 2. These VLANs need to span switches and travel across the LAGs. So what I have set up and is apparently wrong...

Switch 1 (I eliminated the QoS cruft from the top):

!
interface vlan 1
ip address 192.168.15.23 255.255.255.0
!
interface vlan 2
name "Wifi - Public"
!
interface gigabitethernet1/0/45 -----> Access to untagged devices on VLAN2
switchport general allowed vlan add 2 tagged
switchport access vlan 2
switchport general pvid 2
!
interface gigabitethernet1/0/4 -----> Access to untagged devices on VLAN2 which would go to a router for public wifi access.
 switchport general allowed vlan add 2 tagged
 switchport access vlan 2
 switchport general pvid 2
!
interface gigabitethernet1/0/47 ---> LAG1 port 1
channel-group 1 mode auto
!
interface gigabitethernet1/0/48 ----> LAG1 port 2
channel-group 1 mode auto
!
interface Port-channel1
description LAG1
switchport mode trunk
!
ip route 0.0.0.0 0.0.0.0 192.168.15.1
 
Switch 2
 
!
interface vlan 1
ip address 192.168.15.24 255.255.255.0
!
interface vlan 2
name "Wifi - Public"
!
interface gigabitethernet1/0/1 -----> Port receiving the tagged packets from the wifi AP
switchport mode general
switchport general allowed vlan add 1-2 tagged
switchport general acceptable-frame-type tagged-only
switchport general pvid 4095
!
interface gigabitethernet1/0/45 -----> Access to untagged devices on VLAN2

switchport general allowed vlan add 2 tagged
switchport general pvid 2
!
interface gigabitethernet1/0/46 -----> Access to untagged devices on VLAN2
                
switchport general allowed vlan add 2 tagged
switchport general pvid 2
!
interface gigabitethernet1/0/47
channel-group 1 mode auto
!
interface gigabitethernet1/0/48
channel-group 1 mode auto
!
interface Port-channel1
description LAG1
switchport mode trunk
!
ip route 0.0.0.0 0.0.0.0 192.168.15.1
 
 
I would expect SSID2 to be able to ping any device on ports 45 and 46 on either switch. Then SSID1 should be able to ping ports 2-44 on either switch (I figure switch 3 will be easy enough to rope in once I get this figure out on the first two). Hopefully this makes sense and someone call tell me where I have run amuck.

Thanks!




  • 279

    0

    Posted October 12th, 2012 14:00

    The wifi device sends all tagged traffic.

    !

    Right now I have (just showing relevant ports)

    interface gigabitethernet1/0/1

    switchport mode general

    switchport general allowed vlan add 1-2 tagged

    switchport general pvid 4095 ---> I only want to allow tagged traffic thereby preventing rogue devices

    !

    interface gigabitethernet1/0/45
    switchport access vlan 2

    !

    So in trying to ping from 1/0/1 (SSID2 tagged with VLAN 2)   to a device on port 1/0/45 which is just a dumb PC with no VLAN awareness, pings  fails

    However, when I ping from 1/0/1 from the SSID tagged with VLAN 1, I can ping no problem to other devices on VLAN1.

    I am forgetting about the LAG for the time being until I can get the VLANs working on a single switch.