Solved: Cisco 6504E : two core switches - need redundancy

ITexpert · ‎09-04-2018

Hello Guys,

My 6504E does not have the SUP cards which support VSS.

Please provide me the alternative ways to configure redudancy for intervlan routing.

Right now SVI's are configured on both switches but SW-1 is default gateway for all vlans and doing the routing to firewall.

I want that if Sw-1 fails SW-2 takeover.

both switches are connected to firewall with STP for now.

Thanks

Reza Sharifi · ‎09-04-2018

Hi,

according to my knowledge, I have to make root bridge switch as active and other switch as the standby switch.

That is correct. Make sure whichever switch you pick to be the primary for VRRP, is the root bridge and the other switch is back up.

I am bit nervous because i never did on SVI interfaces, please provide all the cautions ? I also have local dhcp service for some vlans on coreSW-1, how that will work in case of failure ?

I am sure you have SVI interfaces on the core right now. So, what you have to do is to create an SVI for each vlan on both switches and configure them with VRRP. You would need to give the primary switch a higher VRRP priority, so it is the master and leave the backup switch as default (100).

For example, you can use one vlan for testing and if everything goes ok, configure the rest of the vlans. You would need to do this in a maintenance window in case of any issues and downtime.

see this doc for vrrp config example:

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipapp_fhrp/configuration/xe-3s/fhp-xe-3s-book/fhp-vrrp.html

HTH

View solution in original post

Reza Sharifi · ‎09-04-2018

Hi,

If you have a layer-2 link (trunked) between the 2 switches, you can use VRRP or HSRP to provide redundancy for user vlans. This way, if one switch fails, you have a second one to forward traffic.

HTH

ITexpert · ‎09-04-2018

Hello Reza,

I am planning to go with VRRP because our firewall is not cisco.

according to my knowledge, I have to make root bridge switch as active and other switch as the standby switch.

I am bit nervous because i never did on SVI interfaces, please provide all the cautions ? I also have local dhcp service for some vlans on coreSW-1, how that will work in case of failure ?

Thanks

Reza Sharifi · ‎09-04-2018

Hi,

according to my knowledge, I have to make root bridge switch as active and other switch as the standby switch.

That is correct. Make sure whichever switch you pick to be the primary for VRRP, is the root bridge and the other switch is back up.

I am bit nervous because i never did on SVI interfaces, please provide all the cautions ? I also have local dhcp service for some vlans on coreSW-1, how that will work in case of failure ?

I am sure you have SVI interfaces on the core right now. So, what you have to do is to create an SVI for each vlan on both switches and configure them with VRRP. You would need to give the primary switch a higher VRRP priority, so it is the master and leave the backup switch as default (100).

For example, you can use one vlan for testing and if everything goes ok, configure the rest of the vlans. You would need to do this in a maintenance window in case of any issues and downtime.

see this doc for vrrp config example:

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipapp_fhrp/configuration/xe-3s/fhp-xe-3s-book/fhp-vrrp.html

HTH

ITexpert · ‎09-04-2018

Thanks alot, Reza .. Really appreciated/