core switch redundancy

[Manish Manwal]

hi all, i want to know something about core switch redundancy, when we connect two core switch with stack cable and want to both switch as active active, is it possible? if one switch goes down then what happen? and if both are working then, are they working with by distribute work load with each other.

[Damien Miller]

Since you mention using a stack cable I will assume that you are levering catalyst 2000 or 3000 series switches. When two or more switches are stacked, the work is split up between members. The primary (master) as identified in the "show switch" command output. The master can also be identified from the front panel lights.

The switches in a stack can all be used to forward traffic, every port is available to configure and use as a normal switch. If the master switch fails then the next member based on priority takes over the role of master. The new master will have the same configuration and management address.

Where the processing for some functions and features takes place depends on the catalyst model, there have been many revisions of stackwise over the years. Think of it as a distributed workload, you won't have 24/48 ports of a second switch sitting idle unless the network is configured that way.

[balaji.bandi]

adding to other post.

what is the requirement for Active/Active ? what kind of environment is this ?.

if your end device connected to 1 leg of connection, there is no requirement for Active /Active here design point of view.

but this suggestion based on your input, if you can share your topology and requirement, best can be suggested in this forum

[Manish Manwal]

please see the attachment. how we can add redundancy switch. what is the best practice.

[balaji.bandi]

As per your diagram, you do not have redundancy links from Core to Distribution and distribution to Access layer.

Are you looking to re-design your campus design ? I have just added rough connection between cores and also suggested design between distribution to core also.

I have also seen the information you have ditribution different location, how are you terminating those connection back to core ? Over VPN ?

more information can be find here :

https://www.cisco.com/c/dam/en/us/td/docs/solutions/CVD/Campus/CVD-Campus-LAN-WLAN-Design-Guide-2018JAN.pdf

[Manish Manwal]

Are you looking to re-design your campus design ?
ans:- no
I have also seen the information you have ditribution different location, how are you terminating those connection back to core
ans :- over fiber links.
for redundant link from distribution to core we can use another core of fiber link.
actually, i want to know how we can what is the best way to connect or create redundancy. between core's.
forget about our network, assume that we are going to create a new network structure, then??

[balaji.bandi]

I have provided the best option for the cisco best practice, and i have also given CVD, you need to understand the CVD and design as per your requirement.

if you looking all resilence end to end, you need to have all dual links, each level of redundancy, so services will be available all the time.

forget about our network, assume that we are going to create a new network structure, then??

Follow the cisco Design.