DAD link c9407 VSS

[jordon.eadington]

Hi 

I have configured 2 x 9407 as VSS running IOS Gibraltar-16.12.4

When i fail the VSLs (currently running 2 x 40g) between the SUPs, the active switch shuts down as its suppose to. When i replace the VSLs, the switches recover as they should do, but one of the DAD interfaces shows up and the other shows down (as below)?? I have the DAD links connected together via cat6a, both switches have C9400-LC-48UX line cards installed. 

When i fail the switches for a 2nd time, the active shuts down again, so the DAD link is working ok, but the one interface is still showing down? is this a known bug?

I have tried with 10g fibre connection and works ok, but I would like to use copper. 

Switch#sh stackwise-virtual dual-active-detection
In dual-active recovery mode: No
Recovery Reload: Enabled

Dual-Active-Detection Configuration:
-------------------------------------
Switch Dad port Status
------ ------------ ---------
1 TenGigabitEthernet1/5/0/48 up
2 TenGigabitEthernet2/5/0/48 down

Thanks

Jordon

[balaji.bandi]

You looking 2 ports to in DAD link ? are they part of Port-channel

if not i would suggest to be part of the port-channel

[jordon.eadington]

Hi BB,

No port channel. Just 1 physical connection (cat6a) between the two switches. Config below. 

int t1/5/0/48
stackwise-virtual dual-active-detection
!
int t2/5/0/48
stackwise-virtual dual-active-detection

Thanks

Jordon
!

[Reza Sharifi]

Hi,

Are you using the sup port for DAD?

• Dual-active detection (DAD) and StackWise Virtual (SVL) link configuration must be performed manually and the device should be rebooted for the configuration changes to take effect.

• Fast Hello dual-active detection is supported only on supervisor module ports. Enhanced PAgP dual-active detection is supported on supervisor module ports and line cards.

• https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9400/software/release/16-9/configuration_guide/ha/b_169_ha_9400_cg/configuring_cisco_stackwise_virtual.html
• HTH

[jordon.eadington]

Hi Reza,

Thanks for your reply.

I am running 16.12.4 sw. In 16.12.2 release notes, states that i can use line cards for DAD.

I am using 40g x 2 links for SVLs, which disables the other ports on the SUP card. I think this is due to 80g max on the SUP. 

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9400/software/release/16-12/release_notes/ol-16-12-9400.html#concept_kp2_1ps_pjb

Thanks

Jordon

[Reza Sharifi]

Hi Jordan,

I am running 16.12.4 sw. In 16.12.2 release notes, states that i can use line cards for DAD.

I see. I am wondering if it is supported by all 10Gig modules (copper or fiber) as the release does not mention that.

I am using 40g x 2 links for SVLs, which disables the other ports on the SUP card. I think this is due to 80g max on the SUP. 

That is correct. If you use both 40Gig than you can't use the 10Gig. 

Can you do this just for testing:

Use one 40 Gig for SVL and than using a 10Gig for DAD? 

or

Use 2 10Gig for SVL (BTW, 2 10Gig for SVL is more than enough) and use one 10Gig for DAD.

HTH

[jordon.eadington]

Hi All,

Thanks for your replies, I can successfully get it working using any ports (copper or fibre), apart from the Mgig ports that still give the up/down scenario after reload.

Cheers

Jordon

[DavidHutton0858]

Hi Jordan,

Did you get this resolved?  Did you get it working with the 40G for VSS and 10G for DAD?

Rgds,

Dave