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 Fiber Module Compatibility with Firebox M5600 devices

If you have a 2 port 40Gb QSFP+ fiber module for your Firebox M5600, that fiber module might not be compatible with slot D in your Firebox.
To confirm compatibility, look for a RevB sticker in the lower-right corner of the top side of the fiber module. If there is no sticker, your fiber module will not work correctly in slot D of the Firebox M5600. The module will work correctly in any other slot, and you can use other modules in slot D.
Example of RevA and RevB modules