Unlocking Third Party Transceivers on Older Arista Switches

 Like many switch vendors, Arista switches running EOS only accept Arista branded optics by default. They accept any brand of passive direct attach copper cables, but since third party optics tend to cause a prohibitive number of support cases, it's needed to force the user to make a deliberate decision to enable third party optics so they can appreciate that they're venturing out into unsupported territory. 

The thing is, if you're out buying an older generation of Arista switch on eBay to try and learn EOS, you're probably also not able to directly buy Arista branded optics, so the unlock procedure on older switches would be of interest to you. 

EOS has two different methods for unlocking third party transceivers, depending on what hardware you're trying to unlock. It's not dependent on what version of EOS you're running on the switch, so all switches which originally supported the old "magic file" unlock method always supported the old method, and newer switches have always required the customer unlock code. 

  1. The "magic file" method is used on the earlier switches, and depends on EOS checking for a file named "enable3px" in the flash: partition. There doesn't need to be anything in this file; it just needs to exist, so an easy way to create this file from the EOS command line is "bash touch /mnt/flash/enable3px"
  2. The newer "customer unlock code" method instead relies on each customer having a conversation with their account team to get a cryptographic key for their specific account, which is then visible in their running-config as a "service unsupported-transceiver CUSTOMERNAME LICENSEKEY" line
Once you apply one of these two unlock methods, save your running config and reload the switch to have it unlock all your transceivers and accept all future optics you install. 

So if you're looking at a switch on the second hand market and trying to figure out if you can unlock it using the old magic file method, here is a list of the switches which predate the newer customer license key method and work with the empty "enable3px" file:
  • DCS-7120T-4S
    • 20x 10GbaseT
    • 4x SFP+
    • Last EOS version 4.13.16M
  • DCS-7140T-8S
    • 40x 10GbaseT
    • 8x SFP+
    • Last EOS version 4.13.16M
  • DCS-7048T-4S
    • 48x 1GbaseT
    • 4x SFP+
    • Last EOS version 4.13.16M
  • DCS-7048T-A
    • 48x 1GbaseT
    • 4x SFP+
    • Last EOS version 4.15.10M
  • DCS-7124S
    • 24x SFP+
    • Last EOS version 4.13.16M
  • DCS-7124SX
    • 24x SFP+
    • Last EOS version 4.13.16M
  • DCS-7124FX
    • 24x SFP+
    • Last EOS version 4.13.16M
  • DCS-7148S
    • 48x SFP+
    • Last EOS version 4.13.16M
  • DCS-7148SX
    • 48x SFP+
    • Last EOS version 4.13.16M
  • DCS-7050T-36
    • 32x 10GbaseT
    • 4x SFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7050T-52
    • 48x 10GbaseT
    • 4x SFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7050T-64
    • 48x 10GbaseT
    • 4x QSFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7050S-52
    • 52x SFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7050S-64
    • 48x SFP+
    • 4x QSFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7050Q-16
    • 8x SFP+
    • 16x QSFP+
    • Last EOS version 4.18.11M-2G
  • DCS-7150S-24
    • 24x SFP+
    • Last EOS version 4.23.x-2G (still an active train)
  • DCS-7150S-52
    • 52x SFP+
    • Last EOS version 4.23.x-2G (still an active train)
  • DCS-7150S-64
    • 48x SFP+
    • 4x QSFP+
    • Last EOS version 4.23.x-2G (still an active train)
  • 7548S-LC line cards on an original 7504/7508
    • 48x SFP+ line cards
    • Last EOS version 4.15.10M
    • None of the E series or R series line cards support the magic file method
So hopefully you find that list helpful.

If you're looking to unlock transceivers on newer switches, I'm afraid I'm not able to help there. You may try filling out the "contact sales" form on the Arista website and have a conversation with your account rep about what you're trying to do. Don't contact TAC or support; they're never authorized to hand out unlock keys and will only refer you to your account team. 

Popular Posts