How to connect 2 Cisco MDS9k switches over dark fiber (20 km / 12.5 miles)

I was just checking the MDS9222i and also found no SFP's to support distances over 10km. So why buy a 9222i at all ?

RRR

Try this cisco part number: DS-SFP-FC-2G-LW

That part still has a 10k limit.

Even the DS-SFP-FC-4G-LW can only reach 10km. So the -SFP- one isn't good enough. We need the CWDM's.

I found it out: DS-CWDM-1470 is enough for 30km (4Gb) and 60km (2Gb) in the MDS9124.
Furthermore I need attenuators for reducing the laser strength to prevent the Tx from burning in too fast.

I don't need a MUX/DEMUX for CWDM, since it's a point to point connection. However: a MUX/DEMUX is not that expensive and pays itself back within 2 years in our case.

Rob,
Thanks for sharing the solution with us. I was curious what the end solution would be. Can you describe briefly the overall solution and the components required to make it work. I have never had to connect fabrics over a distance that great.

Thanks,
Aran

- Cisco MDS9124 on both sides
- dark fiber (2 fibers per channel, 1 for Rx and 1 for Tx)
- distance about 12.5 miles
- 1 Cisco DS-CWDM-1470 in each switch
- one 15216-ATT-LC-10= attenuator per receiving end (per SFP) to weaken the signal, so the signal doesn't burn in the Tx

There's no need to a mux/demux, since we're attaching point to point, so just like ANY other SFP.




So in our case:
2 x 2 MDS9124 (2 on each side)
4 of those long wave SFP's, each in every switch
2 dark fibers (1 switch on each end)
4 attenuators

Thanks for sharing Rob

You're welcome