V400 Stacking with two X690 and 3rd party optic

[Andreas_Prott]

does someone ever try to build a V400 Stack with two X690 and 3rd party optics? I use OEM QSFP28 Transceiver - Extreme 10403 Kompatibel 100GBASE-LR4 QSFP28 1310nm 10km.
In a native 100G Port we got a link at any time, but on the V400 stacking ports 61 and 69 the optic stay dark, no link. Does someone have any experience with OEM optics and V400 stacking?

Best regards
Andreas

[Stephane_Grosj1]

Just listing here, for future reference, the below CLI command, available with 22.6p1-1 and p2-1.

configure stacking-support stack-ports all selection native V400 alternative-configuration

Slot-1 Stack.2 # conf stacking-support stack-ports all selection native V400 alternative-configuration
This setting will take effect at the next reboot of this switch.

Slot-1 Stack.1 # conf stacking-support stack-ports all selection native V400 help
V400 is the default mode which sets the stack ports to 106G
V400 alternative-configuration is required when using specific fiber cables.
This mode sets the stack ports to 100G, enables pre-emphasis and FEC (clause_91).
Cables requiring alternative-configuration include:
QSFP28 SR4
QSFP28 LR4
QSFP28 CWDM4
QSFP28 PSM4
QxQ AOC cable - 5m
QxQ AOC cable - 7m
QxQ AOC cable - 10m
QxQ AOC cable - 20m
See the EXOS Hardware Installation Guide for a complete list of supported cables

[Axel_Reusch]

Unfortunately, I can't provide any further technical input, as my end customer decided to use the original extreme networks DAC cable instead of QSFP28.

Any further information on the use of QSFP28 (including the exact type) when using the EXOS 22.5 and higher is very welcome.

BR,
Axel

[ReneD_]

Hi,
are there any update to this topic? Is the "100Gbit Stacking via Fiber problem" solved? Does the stacking function probably via LR4 QSFP28?

BR,
Rene

[Axel_Reusch]

Hi Rene,

according to 22.6.1 Release Notes Nov. 2018 open issues in section "Optics":
xos0072483 - ExtremeSwitching X690, X870 and X590 series switches do not support 100G Optic/AOC cables on stacking ports.

Additionally Q&A last modified on 11/22/2018:
"Do X690, X870, X590 switches support AOC cable on stacking ports?
Answer:
"Currently, X690, X870, and X590 switches don't support AOC cable on stacking ports and the maximum supported length for DAC is 5 meter which is not sufficient for customers who prefer to keep stack nodes at a longer distance.
The feature is documented and will be implemented via CR xos0072483 in an upcoming EXOS releases."

I would also like to know if there is a patch/fix available for this. May be in 30.1.1? Release Notes of 30.1 do not answer this unfortunately.

BR,
Axel