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Shailender_1542's avatar
Shailender_1542
Icon for Nimbostratus rankNimbostratus
Jan 30, 2016

Cross Connectivity with Switch for Access and Trunk Port ?

Hi Champs ,

 

I have below questions , please help to resolve issue..

 

I have 2 LB (LB-1 and Lb-2 ) and 2 Switches ( Sw-1 and Sw-2)

 

1st Case.:

 

LB1-eth1.1 connected to Sw1-port1 LB1-eth1.2 connected to Sw2-port2 LB2-eth1.1 Connected to Sw2-Port1 LB2-eth1.2 Connected to Sw1-Port2

 

Above all interfaces part of VLAN-10 ( LB-1 IP : 1.1.1.1/29 LB-2 IP : 1.1.1.2/29 VIP : 1.1.1.3/29 Sw-1 IP : 1.1.1.4/29 Sw-2 IP : 1.1.1.5/29 Vrrp : 1.1.1.6/29

 

Case 2:

 

LB1-eth1.3 connected to Sw1-port3 LB1-eth1.4 connected to Sw2-port4 LB2-eth1.3 Connected to Sw2-Port3 LB2-eth1.4 Connected to Sw1-Port4

 

These are configured as Trunk to carry 2 VLANs VLAN-20 and Vlan 30 vlan20 LB-1 IP : 2.1.1.1/29 Vlan20 LB-2 IP : 2.1.1.2/29 Vlan20 VIP : 2.1.1.3/29 Vlan20 Sw-1 IP : 2.1.1.4/29 Vlan20 Sw-2 IP : 2.1.1.5/29 Vlan20 Vrrp : 2.1.1.6/29

 

vlan30 LB-1 IP : 3.1.1.1/29 Vlan30 LB-2 IP : 3.1.1.2/29 Vlan30 VIP : 3.1.1.3/29 Vlan30 Sw-1 IP : 3.1.1.4/29 Vlan30 Sw-2 IP : 3.1.1.5/29 Vlan30 Vrrp : 3.1.1.6/29

 

Please suggest if above all scenarios will work or not. would be great help for me..

 

application delivery
BIG-IP
LTM

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  • IanB's avatar
    IanB
    Icon for Employee rankEmployee
    Feb 04, 2016
    LB1 1.1  -  SW1-1
LB1 1.2  -  SW2-2

LB2 1.1  -  SW2-1
LB2 1.2  -  SW1-2

    If you connect it up as above, with no other config, then you'll be putting a loop in your network, and spanning tree on your switch will block one of the ports.

    But you can achieve this by using an aggregate link (port-channel in Cisco terminology) across both switches, as long as the switches are also set up to act as a single switch using (VSS or vPC)[http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-6500-series-switches/white_paper_c11_589890.html])

    Note that there is some ambiguity around the word 'trunk', which Cisco uses to refer to a link that contains more than one VLAN, and most other vendors (F5 included) use trunk to refer to an aggregate link containing multiple physical links, and which optionally uses LACP as a control protocol. Cisco calls this a port-channel.

    We have some more information on using Cisco VPC with F5 devices in SOL13142