I'm hoping I'm not the first to run into this issue.
I've recently purchased 2 EWDM MUX's to use with 10Gig Xenpak interfaces stuck into ws-6704-10ge blades on 6509-E chassis'.
There are three different frequency transceivers in each of the 6509-Es. I have single mode LC-SC patches connecting the transceiver with their partner inputs in the EWDM MUX.
I have both EWDM MUXs connected to each other via the 'Network' input using LC-LC single mode cable (this is a test bed). The cables are 2 meters long and I am using 5dB attenuators connected to the 'Network' input of one of the MUXs.
Porblem: I am not getting any link from my transceivers to each other, and I don't know why.
I was wondering if the attenuators weren't working, but I don't have any idea how to test those...
I am pretty sure I've got the setup correct (well as far as the installation guide that came with the mux tells me), but it won't be the first time I've missed something.
Can anyone here give me a clue or an idea of what to do to troubleshoot this?
Any help will be very much appreciated.
Do you have the LC-LC singlemode jumper cable between the AMP IN and AMP OUT ports on the MUXes. This is required to get signal from the DWDM input ports and the NETWORK ports.
If you test the two 6509s with a 2 meter patch cord (without the MUXes), you will need the 5dB attenuator. Once the MUXes are installed, no attenuation should be necessary.
Your 17km of singlemode fiber should have approx 4.25dB of loss (17km x .25dB loss per km) plus any splice losses (which can be significant if old mechanical connectors are used at in intermediate sites in the link). The link loss can be verified by using a simple optical power meter (fairly inexpensive these days to buy). An OTDR trace would allow you better visibility of any other fiber abnormalities and individual splice losses, again, to provide a baseline for future troubleshooting.
It is recommended that the fiber links be documented before final turn-up of the system. This allows a baseline for future issues that may arise and makes troubleshooting easier.