Serial console connection Foundry Bigiron <-> Sun Fire Vxxx

At a remote location I have a Foundry Bigiron 4000 router. I put up a cheap Sun Fire V100 sparc-based server to which I wanted to connect the serial console of the BigIron.
The Sun Fire v100 has a RJ45 serial connector, and the Bigiron a DB9 (male) serial connector. So the first thing I tried is to use a standard Cisco console cable which fits right in between the two devices.

Unfortunately this didn’t work.. As a reference I tried to connect to a HP Procurve switch which also has a DB9 male connector. This did work!
Now the difference between de DB9 ports on the HP and the Foundry is that the Foundry is a DCE based port, and the HP a DTE.
This means you should setup the connection to the HP (from a PC) as straight cable, and to the Foundry as a null-modem.
As the cisco cable was a straight-cable, I needed to fix my own DB9 to RJ45 foundry cable. I had a few DB9-to-RJ45 adapters lying around, with which you can make your own adapter.

I couldn’t find the right layout on the internet.. so I figured it out myself using the pinouts of both connectors. See below. The colors mentioned are from the RJ45->DB9 adapter you can buy at any radio shack.


    Sun Fire serial RJ45              Foundry BigIron console DB9  
     S/GND  5 (green)  ---------------------  5  S/GND
     TXD    3 (black)  ---------------------  3  RXD
     RXD    6 (yellow) ---------------------  2  TXD
     CTS    8 (white)  ---------------------  8  RTS
     RTS    1 (blue)   ---------------------  7  CTS

For reference.. here the Foundry DB9 pinout:

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