In my home network/lab, I was previously using a 24 ports Cisco 2960 as the breakout switch from my LAB into my LAN. It was later replaced to a 24 ports Cisco 3550 L3 switch. Problem was, believe it or not, I started running short on ports.

Besides, I was also missing Juniper switches in my lab so it was just a matter of time before getting one. I just had to decide between getting the one 48 ports switch, or two 24 ports switch.

There are benefits in having two and being able to configure a virtual chassis, was just one of those.

So here is how my Lab/Home network switching physical topology looks like now.


In this diagram, my two Juniper EX 2200 switches are depicted at the bottom. You can see that I’m using the first two ports, ge-0/0/0 and ge-0/0/1 as the VCP ports.

Here is how my configuration looks like:


  • preprovisioned – this keyword is mandatory when configuring VC in pre-provisioned mode
  • no-split-detection – this is optional in the sense that JunOS will not “complain” if you omit it. However, this is recommendable in this case, as explained in Part I
  • we are then tying each member switch to a specific role, based on the serial number

You can see below the actual set commands:


You can get the serial-numbers for each swich using the following command:


Notice you are seeing here the SNs for both switches since they are already clustered.

Also notice that both switches are set to be routing-engines – so which one is the primary and which one is the backup routing engine? The answer to this question is given in the Part I – see the Election Process

To configure the actual VCP ports, I used the following commands:

run request virtual-chassis vc-port set pic-slot 0 port 0
run request virtual-chassis vc-port set pic-slot 0 port 1 

Next, let’s take a look at some verification commands…

show virtual-chassis – an brief overview of the current virtual-chassis status


show virtual-chassis protocol (…) – I mentioned in part I that VCCP cannot be configured; we can however use this command tho check adjacencies, stats, etc.


show virtual-chassis vc-path (…) – this can be very useful in specific troubleshooting scenarios. You specify a source and destination interface and the output shows you the how many and which hops are used when switching the frame.


show virtual-chassis vc-port – to display the VCP ports. Below you can see that one of the VC-Ports is down; this is because I have only connected ports g-0/0/1 on each switch.


Interesting to see is also the output of the show interface terse command:


Notice how ge-0/0/0 & ge-0/0/1 have disappeared; they have been now replaced by the VCP ports.


Thank you,
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