HSRP on VPC

[haitham.jneid]

Hi experts,

kindly check the attached file.

let's say that port-channel 50 and 60 are in trunk mode and they are carrying vlan 20,30,40. is it possible to create back to back HSRP for vlan 20??

on nexus and access switches.

also is it possible to create HSRP on the access switches on vlan 20 so when nexus is forwarding toward access, its gateway will be the VIP for vlan 20 configured on both access switches. how is the returning traffic will be forwarded from access switches to nexus??

thanks,

Haitham Jneid

[ahmedshoaib]

Hi;

HSRP provides first-hop routing redundancy for hosts with a group of L3 Devices (Router/L3 switches). You can create & run HSRP between Core/Distribution/Access switches. But in this scenario you feel issue or traffic slowness in case of primary (high end device) fail and traffic shifte to Secondary (access switch). 

It's always recommend to run HSRP on your core/distribution switches. In case of Nexus there is a feature peer-gateway which will allowed both Nexus switches will act as a gateway and forward the traffic to next L3 hop instead of sending traffic to HSRP active Router/Switch.

Lets take your topology, access switch connected to both Nexus 7000 in vPC environment with trunk & allowed vlan 20(i.e 20.20.20.1 is HSRP VIP, .2 primary & .3 secondary Nexus). User (IP-20.20.20.100) connected to access switch want to access Server. It's traffic forward to access switch, due to port-channel configured on access switch it will do load-balancing, to reach the gateway (20.20.20.1) might be your traffic forward to secondary Nexus 7000 (20.20.20.3). With the help of peer-gateway the traffic will forward toward next L3 hop.

Thanks & Best regards;

[haitham.jneid]

Hi Ahmed,

appreciate your support. I got your point but I need to know if it is applicable to have vlan 30 on both access switches and configure HSRP for this VLAN so nexus is sending traffic to the VIP of VLAN 30.

is it applicable in such design?

thanks,

Haitham Jneid

[ahmedshoaib]

Hi;

It's always recommend to configure the SVI on either Core/Distribution switch not on access switches. Access switches will be used user/server connectivity.

Thanks & Best regards; 

[haitham.jneid]

Hi Ahmed,

what if we replace the access switches with 2 routers carrying VLAN30 through the nexus switches and configure HSRP between these 2 routers over vlan 30. signaling for hsrp will be via nexus. and now nexus can send traffic to the VIP of HSRP 30.

is it applicable like this, because I have same scenario and need to know.

thanks,

Haitham Jneid

[ahmedshoaib · Accepted solution]

Hi Haitham;

Yes you can. It's total depend on scenario and it's requirement.

Thanks & Best regards;