Problem With Port QSFP+ 40G to 4x10G


I have the following situation:

I have a Switch summit x670. I have configured 2-port QSFP + as 4x10G each, in which I am connecting a cable with MPO connector to 6 lc connectors.
The problem is that when I connect the cable, I have no link nor in the QSFP + port, nor in SFP + ports.
I have configured the ports to 10000 speed, full duplex, auto off. I have also assigned four vlans tag and untag one in each port 10g.
I appreciate the support.
Sorry for my bad English.

5 replies

Userlevel 5
Hi Nahum,

I assume that you have a SummitX-670V with a 40 gig VIM module.
I don't know your exact cable assembly but we only support a QSFP+ break-out cable with 4 lc connectors.

Please clarify your environment.


hi Ron

My cable is 6 lc connectors. I suppose that's the problem. You think I can run with this cable?
Because already purchased.

Thanks for the answer.

Userlevel 5
Hi Nahum,

Unfortunately it is not possible to use this type of cable. The QSFP in 4 x 10gig mode will only support a breakout cable with 4 lc connectors.

Hi Ron
Thanks for responding

You could confirm if it works with the following breakout?

40 Gigabit Ethernet QSFP 40GBase-SR4 to MTP(MPO)/LC (4 Duplex LC) 1/2 Meter Breakout Cable, OM3, 50/125, 3 meter.
  • Connector A) MTP/MPOfemale
  • Connector 😎 LC/UPC
  • 40Gb pin-out configuration
  • Jacket Type: Plenum Rated (OFNP)
  • Jacket Color: Aqua (blue)
  • Fiber Mode: Multimode 50 Laser Optimized OM3
  • Breakout Length: 1/2 Meter (~24 Inches)
  • Cable type: Corning 3mm round to 2mm on the breakout side
  • Fiber Count: 8 Fibers

Thanks for the support

Userlevel 5
Hi Nahum,

I think that is the right cable. It does look similar to the one I have.
All connectors seems the right type as well as the fiber type.

For proper clarification, you can contact your local SE.