Juniper Networks EX4200 Muli-Layer Switch


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Juniper Networks EX4200 multi-layer Ethernet switches are fast, secure and reliable platforms providing compact standards based connectivity for branch office, enterprise networks and data centers. Yes, if you haven’t guessed by now, we really like these switches.

Designed for the access and distribution layers, the EX4200 and EX3200 series switches allows Juniper to enter markets primarily dominated by the Cisco Catalyst line of switches.

The EX4200 series switches combine the high reliability of traditional chassis based systems with the economics and flexibility of stackable systems.  Available in both 24 port and 48 port configurations, these switches provide standards base 10/100/1000 Mb/s copper connectivity.  Also available is a 24 port fiber configuration for distribution and core deployments.

Why pay for a full PoE switch when you only have a hand full of PoE devices?

Full or partial configurations of Power over Ethernet (PoE) are available to deliver 15.4 watts of  class 3 power per port.  Why pay for a full PoE switch when you only have a handle full of PoE devices? This flexibility allows Juniper to stand out from the crowd and save you money.  The ex4200 standards based P0E configurations allow you to support converged networks for separate data, voice and video networks.

Optional front panel fiber uplink ports are available to provide connectivity to distribution layer switches or upstream routers.  These hot swappable modules come in either a 2 TenGigabit module or a 4 One Gigabit module configuration.

Juniper’s Virtual Chassis Technology means you only have to worry about one software image, one config file and one IP address

The Juniper virtual chassis technology is another feature that makes the EX4200 very unique.  This unique feature allows up to ten switches to be connected into a single logical device.  This also means a single JunOS software image, a single config, and a single IP address for management.

Inter-connectivity is provided by a high speed non-blocking connection on the back of each switch.  This 128Gb/s back plane connection is cabled in a daisy chain fashion very similar to a Cisco catalyst 3750.

The virtual chassis technology also works over the front panel up-link ports allowing switches to be deployed on separate floors or in separate building across a campus.

In a virtual chassis configuration, the switches automatically elect master and backup routing engines to maintain the hardware forwarding table and routing protocol states. In the event of a master routing engine failure, a graceful fail-over to the backup routing engine occurs immediately to ensure continued operations.

The Chassis like features of the ex4200 continue with redundant hot swapable power supplies and redundant hot swappable fan assemblies too.

Check this video introduction on Juniper Networks Virtual Chassis technology.

The EX4200 hardware easily competes with any of Cisco’s multi-layer switching platforms and does so for a whole lot less money.  Coupled with the JunOS operation system, which allows for configuration revision control, and simultaneous config administration, the EX4200 switch is a must have replacement for all aging Cisco gear or new deployments.

Do you have any EX4200’s in your network?  What is your experience with Juniper’s enterprise class switching series? Leave a comment below and let know what your experience has been.


5/5 - (1 vote)



Senior Network Engineer, technology enthusiast, guitar and bass player. Joe Wilson is the creator of as well as other niche websites that can be found around on the Internets.

What do you think about this article?


  1. We have a 5 unit chassi as our core switch and it has been nothing but good. We replaced an old HP Procurve 4108 with the chassi.

    A few weeks back we found out the hard way that one port had died in one of the chassi switches. Reported to Juniper, the sent an RMA and I had a new switch in a couple of days. Upgraded the new switch to the right Junos release that we had in the other four switches in the chassi, put it in, stuck in the chassi cables, when into the conf and replaced the old switch serial with the new switch serial and it got the old switch config, with vlans, comments on each port etc. in a few sec.

    This is good shit … keep up the good work Juniper.

    We are now in the process of implementing 2 Juniper SRX650 firewalls, 2 Juniper IC and 2 Juniper SA SSL VPN boxes together with a Juniper NSM to get central administration of all our Juniper equipment.

    Just a lot of Thumbs up from Sweden.

  2. We had 2 "stacks" (3 in one virtual-chassis, and 2 in another) of EX4200 switches where I work and have had our fair share of JunOS bugs and problems. We used them as our SAN switch and although they performed well, they just weren't as reliable as the Cisco gear we have. They were in service for 2 years and we had 2 RMAs because of hardware problems… of which took our storage network to its knees. We also had to upgrade the JunOS software every 3-6 months because we were hitting software bugs. What really concerned me was the fact that the last bug we hit was actually in the FreeBSD Unix kernel. This was very surprising since the Juniper salespeople play the "Unix-stability" card. We were using these as simple Layer2 switches and it was surprising how many weird issues we were having.

    JTAC was also a struggle because of the language barrier….most of JTAC was Indian.

    The CLI was a struggle to learn as well for someone like me that's very strong in IOS CLI. However, after a few months on it I started to like it more than IOS CLI…….the rollback and being able to commit configs with rollback timers were really nice features to have.

    In the end, it was not a good solution for our environment and they were replaced when we consolidated our old Cisco 6509's (Sup2) into Cisco 6509's in VSS.

    They are great bang-for-the-buck, but they don't live up to the hype IMO.

    • I hear what you're saying about JTAC. I tried transferring my case several times, but nobody spoke good enough English to understand. The new Juniper stuff kicks ass on paper. I just wish they had some more QA and testing before releasing something full of bugs.

      I am still waiting to deploy some SRX firewalls, but it's been over a year and while the code has gotten better, there are still significant bugs that prevent me from putting them into production.

      • We also looked into the SRX line of Juniper Firewalls and quickly went another direction……Check Point. We had old NetScreens and tried Fortinets (what a big mistake that was) so naturally we were going to go back to NetScreens but Juniper is making them so darn expensive to lure people into the SRX line of Firewalls. The SRX needs a few more months/years to mature before it is a contender in my opinion.

        We've been really happy with the Check Points though……their advanced routing engine on SPLAT appliances can be a little difficult, but their logging capabilities make up for it. The support we have been getting from them has also been fantastic…..usually we are getting good-ol-boys from Texas helping us out.

  3. I think the term "review" for this article is misleading as this reads like a sale brochure. A review typically tells you the reviewers experiences using the box and their opinion of it's capabilities. This just parrots whatever Juniper said.

    I just discovered RouterFreak recently and as this was the first review I read on the site I was really disappointed. You could have posted the exact same article with the same title but drop the word "review" and it would have been fine.


    • Point taken Dave and you are right. I changed the article title and removed the word review. I had originally wanted to do a full review however the demo unit had to be returned before I could get the review started.

      Thanks for the visit and the comment!

  4. Say goodbye to Cisco catalyst 3750 switches. Juniper EX4200 are far superior.

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