Tag Archives: het-3012

Get rid of your fiber converter (tranciever)

Background
I live in a so called “Telia house” (internet, tele and tv are supplied by telia). These services are provided via fiber at my house, and its actually fiber all the way to the patch panel in my apartment. The connection is then coverted from 1000Base-X to 1000Base-T using a media converter from CTS (HET-3012). Maybe a year ago the media converter failed and my connection was down for almost two weeks. It was at that time I got the idea to get rid of the media converter and have the incoming fiber directly connected to my router.  This way I could get rid of one possible cause of failure and also save som space in my already packed patch cupboard.

Prerequisites
First of all I needed a network card that could fit into my router (a Soekris 6501-50). The soekris have a regular PCI Express 1x interface so it was pretty easy to get a card from ebay. I got a LR-Link LREC6230PF-SFP which used the Intel I210 chip which is well supported in FreeBSD by the igb driver.

Then I needed to find the correct SFP for my application. My first problem was that my incoming fiber uses a single fiber and not a pair, I had never seen something like this. But after some reading on the internet and a quick look at the CTS documentation i found that it uses 1310nm for TX and 1550nm for RX and SC contact. After that is was a simple task to just get a SFP with the correct specs from https://www.direktronik.se

Installation and configuration
When I had the hardware I needed there was no problem installing it. The network card fitted quite nicely in the pretty small case of my Soekris and the SFP worked out of the box.

Soekris
bidi SFP

In order to load the driver for this specific card at boot I added this line to /boot/loader.conf

if_igb_load="YES"

Since I wanted to keep my “old” IP adress I configured the same mac-adress on the new card as on the old card. (And yes, I also changed the mac of the old card to avoid conflicts).
rc.conf:

ifconfig_igb0="DHCP ether 00:00:24:d0:XX:XX description 'Internet uplink'"

And this is how the final result looks like inside the patch cupboard. The three black cables are antenna cables for the wifi. You can read more about the general setup of my router here.
Connected fiber