Switching

I am planning to add an EX4500 to an existing stack with two EX4200s. To be sure this all works, I am trying to take a single EX4200 as member 0 and the master and add to it a single EX4500. It is not working as smoothly as I thought it would.

First, I made sure the JUNOS versions matched. Then I thought it would simply be a matter of booting the EX4500 after connecting it to the running EX4200 with a single VC cable. Oh, how wrong I was.

Everything I've read about membership election says the EX4200 should be the master, but there is just confusion. I've been trying lots of different things, but both come up as linecards or the EX4500 claims mastership or just gets stuck as a linecard.

What is the right procedure to add a EX4500 to an EX4200 stack. Is there some way to clear off the previous VC information? The EX4500 I'm trying to add seems to remember things between reboots that are not in the configuration despite my efforts to clear them.

I'm also wondering if there is some problem with only using one VCP cable. I only have one long enough to connect the devices for where they are currently situated in the lab.

Answering my own question after doing more research. From,

http://www.juniper.net/techpubs/en_US/release-independent/junos/topics/concept/ex4200-virtual-chassis-hardware-understanding.html

"Junos OS Release 11.1—A mixed Virtual Chassis supports up to two EX4500 switches and up to eight EX4200 switches. EX4500 switches must always be configured in the master and backup roles."

I'm running 11.1R3.5. Guess it may be time to upgrade to the JTAC recommended JUNOS first.

Yeah, the master/backup requirements have changed over time.  In 12.1, and possibly 11.4, can have a mix of 4200 and 4500 in master, backup, and line card roles in any combination up to 10 devices.

I did this on 12.1 using 3x 4200s and 1x 4500.  However, I set up the VC in pre-provisioned mode rather than letting it automatically set itself up.  Also, there was a little quirk due to the mixture of devices types.  I had to explicitly set all of the members to mixed mode (request virtual-chassis mode mixed) to get the full VC to form.

-Chad