Description:

Virtual Port Channel (VPC) is a virtualization technology that makes two interconnected switches appear as a single layer 2 logical node for devices at the underlying access level. This is ensured by the virtual port channel network established via VPC, called the "VPC-Peer-Link". The connected devices can be a switch, server or other network device that supports the link aggregation technology.

This article describes, how VPC can be configured on LANCOM Switches with LCOS SX 5.20 / 5.30.

Either stacking or VPC can be used, but not both.

The VPC implementation in LANCOM switches is not compatible with the implementation of other manufacturers.

VPC must be configured via the serial interface, otherwise the connection to the switch will be lost by changing the management VLAN.

Requirements:

Scenario:

Procedure:

1) Configuring VPC on the VPC-Node-1:

1.1) Changing the stacking ports to the "Ethernet" mode: 

1.1.1) Connect to the first switch (VPC-Node-1) via the serial interface and enter the command enable to gain extended rights.

1.1.2) Enter the command show stack-port to check, which ports are configured in "Stack" mode. In this example the ports 1/0/29 and 1/0/30 are configured in this way.

1.1.3) Modify the following parameters:

1.1.4) Modify the following parameters:

The restart of the switch is mandatory to change the port mode from Stack to Ethernet


1.2) Check the port change and activate VPC:

1.2.1) Modify the following parameters:

1.2.2) Modify the following parameters:

1.2.3) Activate the routing functionality with the command ip routing.


1.3) Configure the Layer 3 interface for the VPC keepalive:

For the VPC keepalive (split-brain detection), both switches require a dedicated layer 3 interface. Either an outband interface (service port / OOB) or an in-band interface (VLAN interface) can be used for this task.

On switches with a service port, LANCOM Systems recommends to use this for the VPC keepalive. Only the XS-6128QF does not have a service port, so a VLAN interface must be configured on it for keepalive.

1.3.1) Configure the Layer 3 interface for the VPC keepalive on the service port (XS-4530YUP, XS-4554YUP, YS-7154CF, CS-8132F):

1.3.1.1) Modify the following parameters:

1.3.1.2) Modify the following parameters:

If the VPC nodes also should be able to communicate with the Internet, a gateway must be specified on the service port as well. Use the command serviceport ip <IP address> <subnetmask> <default gateway> to do this.

In this example, the command is as follows:

serviceport ip 10.10.10.1 255.255.255.0 10.10.10.100


1.3.2) Configure the Layer 3 interface for the VPC keepalive on a VLAN interface (XS-6128QF only):

1.3.2.1) Modify the following parameters:

1.3.2.2) Modify the following parameters:

1.3.2.3) Modify the following parameters:


1.4) Create the VPC domain and configure the VPC keepalive:

1.4.1) Modify the following parameters:

1.4.2) Modify the following parameters:


1.5) Modify the System MAC:

In order for both VPC nodes to represent themselves to downlink switches without VPC support as one device, a virtual MAC address has to be entered on both VPC nodes. 

Modify the following parameters:

To prevent conflicts with other systems, it is recommended to use Locally Administered MAC Address (LAA). If a MAC address generator is used, the U/L Flag = 1 (LAA) should be set.

If additional VPC nodes are operated in the same scenario, it is mandatory to use a different System MAC on these. Otherwiese, this would lead to communication problems!


1.6) Create the VPC-Peer-Link:

The Management VLAN must not pass through the VPC-Peer-Link. In the default settings the VLAN 1 is used as the Management VLAN. If this VLAN should pass through the VPC-Peer-Link, the Management VLAN must be replaced by a dummy VLAN and the routing functionality has be activated.

1.6.1) Modify the following parameters:

1.6.2) Modify the following parameters:

1.6.3) Modify the following parameters:

1.6.4) Modify the following parameters:

1.6.5) Modify the following parameters:

1.6.6) Modify the following parameters:

1.6.7) Modify the following parameters:

1.6.8) Modify the following parameters:

1.6.9) Modify the following parameters:

If the Layer 3 interface for the VPC keepalive was configured in step 1.3.2 on an XS-6128QF, additionally the VLAN specified in this step has to be allowed (vlan participate include 999). Activate the VLAN tagging for the VLAN ID specified in step 1.3.2 (vlan tagging 999). 


1.7) Prepare the Downlink port to the downlink switch:

1.7.1) Modify the following parameters:

1.7.2) Modify the following parameters:

1.7.3) This concludes the VPC configuration on the VPC-Node-1.



2) Configuring VPC on the VPC-Node-2:

2.1) Changing the stacking ports to the "Ethernet" mode: 

2.1.1) Connect to the first switch (VPC-Node-2) via the serial interface and enter the command enable to gain extended rights.

2.1.2) Enter the command show stack-port to check, which ports are configured in "Stack" mode. In this example the ports 1/0/29 and 1/0/30 are configured in this way.

2.1.3) Modify the following parameters:

2.1.4) Modify the following parameters:

The restart of the switch is mandatory to change the port mode from Stack to Ethernet


2.2) Check the port change and activate VPC:

2.2.1) Modify the following parameters:

2.2.2) Modify the following parameters:

2.2.3) Activate the routing functionality with the command ip routing.


2.3) Configure the Layer 3 interface for the VPC keepalive:

For the VPC keepalive (split-brain detection), both switches require a dedicated layer 3 interface. Either an outband interface (service port / OOB) or an in-band interface (VLAN interface) can be used for this task.

On switches with a service port, LANCOM Systems recommends to use this for the VPC keepalive. Only the XS-6128QF does not have a service port, so a VLAN interface must be configured on it for keepalive.

2.3.1) Configure the Layer 3 interface for the VPC keepalive on the service port (XS-4530YUP, XS-4554YUP, YS-7154CF, CS-8132F):

2.3.1.1) Modify the following parameters:

2.3.1.2) Modify the following parameters:

If the VPC nodes also should be able to communicate with the Internet, a gateway must be specified on the service port as well. Use the command serviceport ip <IP address> <subnetmask> <default gateway> to do this.

In this example, the command is as follows:

serviceport ip 10.10.10.2 255.255.255.0 10.10.10.100


2.3.2) Configure the Layer 3 interface for the VPC keepalive on a VLAN interface (XS-6128QF only):

2.3.2.1) Modify the following parameters:

2.3.2.2) Modify the following parameters:

2.3.2.3) Modify the following parameters:


2.4) Create the VPC domain and configure the VPC keepalive:

2.4.1) Modify the following parameters:

2.4.2) Modify the following parameters:


2.5) Modify the System MAC:

In order for both VPC nodes to represent themselves to downlink switches without VPC support as one device, a virtual MAC address has to be entered on both VPC nodes. 

Modify the following parameters:

To prevent conflicts with other systems, it is recommended to use Locally Administered MAC Address (LAA). If a MAC address generator is used, the U/L Flag = 1 (LAA) should be set.

If additional VPC nodes are operated in the same scenario, it is mandatory to use a different System MAC on these. Otherwiese, this would lead to communication problems!


2.6) Create the VPC-Peer-Link:

The Management VLAN must not pass through the VPC-Peer-Link. In the default settings the VLAN 1 is used as the Management VLAN. If this VLAN should pass through the VPC-Peer-Link, the Management VLAN must be replaced by a dummy VLAN and the routing functionality has be activated.

2.6.1) Modify the following parameters:

2.6.2) Modify the following parameters:

2.6.3) Modify the following parameters:

2.6.4) Modify the following parameters:

2.6.5) Modify the following parameters:

2.6.6) Modify the following parameters:

2.6.7) Modify the following parameters:

2.6.8) Modify the following parameters:

2.6.9) Modify the following parameters:

If the Layer 3 interface for the VPC keepalive was configured in step 1.3.2 on an XS-6128QF, additionally the VLAN specified in this step has to be allowed (vlan participate include 999). Activate the VLAN tagging for the VLAN ID specified in step 1.3.2 (vlan tagging 999). 


2.7) Prepare the Downlink port to the downlink switch:

2.7.1) Modify the following parameters:

2.7.2) Modify the following parameters:

2.7.3) This concludes the VPC configuration on the VPC-Node-2.



3) Further steps:

Configure LACP on the downlink switch as described in one of the following Knowledge Base articles:



4) Reading out the VPC status on the VPC nodes:

You can read out the VPC status on the VPC nodes via the CLI command show vpc brief.



 


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