Hi

I dont have enough 10 gig port on lind card,so am thinking to use 5 gig  port(Copper) as EtherChanel in order to create the IP BFD to protect against VSL Failure,what do y think?

Thanks

Hi
I dont have enough 10
gig port on lind card,so am thinking to use 5 gig  port(Copper) as
EtherChanel in order to create the IP BFD to protect against VSL
Failure,what do y think?
Thanks

Hi,

Check out the below link for more info

http://www.cisco.com/en/US/products/ps9336/products_tech_note09186a0080a7c837.shtml

Hope to help !!

Ganesh.H

Hello Alsayed,

this should be possible configuration guide requires a dedicated direct link but it does not say that it must be a tengiga.

To be noted it would be a waste of bandwidth to simply exchange IP BFD messages over a tengiga (it is alread over a GE to be honest)

And configuration example uses GE ports:

Router (config)# interface gigabitethernet 1/9/48

Router (config-if)# no switchport

Router (config-if)# ip address 200.230.230.231 255.255.255.0

Router (config-if)# bfd interval 100 min_rx 100 multiplier 3

Router (config-if)# no shutdown

Router (config-if)# interface gigabitethernet 2/1/48

Router (config-if)# no switchport

Router (config-if)# ip address 201.230.230.231 255.255.255.0

Router (config-if)# bfd interval 100 min_rx 100 multiplier 3

Router (config-if)# no shutdown

see
http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/configuration/guide/vss.html#wp1090844

Hope to help
Giuseppe

Guys

so these ports takes over when the VSL goes down and the VSS uses PFD in order re-form the VSS?is that right?

Thanks

Guys
so these ports takes over when the VSL goes down and the VSS uses PFD in order re-form the VSS?is that right?
Thanks

Hi,

If for some rare reason all VSL connections are lost between the virtual switch members leaving both the virtual switch members up, the VSS will transition to thedual active recovery mode.

In the dual active recovery mode, all interfaces except the VSL interfaces are in an operationally shut down state in the formerly active virtual switch member. The new active virtual switch continues to forward traffic on all links.

Hope to Help !!

Ganesh.H

Hello Alsayed,

actually no:  IP BFD and the other possible methods are used to avoid the worst case that is when both supervisors want to be active because they think the other one is dead.

the result would be two devices pretending to be the same device using the same ip addresses in the same vlans (the SVIs) and creating confusion in all network.

So special care is needed to provide "out of band" heartbeat between the two supervisors and IP BFD, fast hellos and Enhanced PAGP have this objective.

Deployment of more then one method of dual active detection is recommended:

so one GE link can be used for IP BFD

one GE link for fast hellos

Enhanced PAGP is different because the out of band heartbeat channel is not built with a direct connection between the two chassis, but by adding informations to PAGP frames that travel over etherchannel bundles:

an access layer switch can use a bundle of  two links one to chassis 1 and one to chassis 2 of VSS

if the access layer switch supports E PAGP some information flow from chassis1 to chassis 2 and viceversa via this third party device.

so IP BFD and the others cannot be an alternate path for VSL but are safety measures to allow the two supervisors to be aware of each other also by  other means.

Hope to help

Giuseppe

Thanks guys