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I'm having trouble configuring a VLAN across two switches (switch A is Cisco 3750G and switch be is a HP Procurve 2824) with Win2k8 R2 servers set up with teamed NIC ports and Gb1 landing on switch A and Gb2 landing on switch B.

VLAN 101 is configured on switch A like this:

interface Vlan101
 ip address
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 load-interval 30

and on switch B like this:

vlan 101 
   name "VLAN101" 
   ip address 
   tagged 1,3,5,7,21 

Is this the correct way to set up the same VLAN on 2 switches?

I then configured a trunking port that connects both switches:

interface GigabitEthernet1/0/21
 description "sw1-sw2"
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 2,100-103
 switchport mode trunk
 switchport nonegotiate
 spanning-tree bpdufilter enable
 spanning-tree bpduguard enable

on switch B I think the trunking is simply configured by putting the trunk port into the VLAN config like I did above.

Now, one server's Gb1 NIC port is connect to switch A and Gb2 NIC port is connected to switch B. I'm using the BACS3 manager to configure SLB teaming of those 2 ports.

A router is connected to switch A (IP: which I set as the gateway address on the servers.

From switch A I can ping (the switch B VLAN 101 address). From switch B I can ping and just fine.

From the server I can ping all addresses just fine as long as Gb1 is up. However, when I shut down Gb1, Gb2 does not take over. Even when I set the gateway address to, I'm not able to ping it.

Am I'm kind of clueless as to what I might be doing wrong here, so any help is greatly appreciated.


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Ok, I guess I just figured it out. On the HP switch the ports connecting to the server NICs need to be Untagged rather than Tagged. Now failover works great between NIC ports

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If that's the case, you didn't configure the second NIC on the server to accept the tagged packets. – womble Nov 28 '09 at 18:21
Yes. Seems like you don't understand the difference between VLAN tagging and just assigning a port to a VLAN. VLAN tagging allows a port to be assigned to multiple VLANs. It does this using the 802.1Q protocol which inserts an additional field in to the ethernet frame between the MAC and EtherType fields. The catch is that your device needs to be configured to looks for this field. Usually this means creating a special VLAN interface on your server which is a child of the physical interface connected to that port. – Kamil Kisiel Nov 28 '09 at 18:52

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