Tuesday, February 14, 2006

 

HSRP and GLBP work fine together.

HSRP and GLBP are similar protocols used for redundancy and load-sharing of routers on a subnet. (VRRP is the non-proprietary version of HSRP; HSRP is a Cisco-specific protocol.) HSRP requires a little more configuration and multiple groups to achieve load balancing while GLBP does the same thing with less configuration. Also, the load balancing that GLBP can achieve can better than with HSRP because with HSRP the load balancing is done manually and not related to actual traffic at any point in time.

The reason I am even thinking about HSRP and GLBP right now is because there was a question on one of the Cisco newsgroups if running both HSRP and GLBP on the same routers would work fine. I thought about it a bit and could not see why anyone would want to do that. In any case, I was curious about this and so I decided to try it on my routers and did just that. I found that the two protocols do work fine when configured simultaneously on the same routers!

Here are the configs I used on the two HSRP routers

Router 1


interface Ethernet1
ip address 192.169.0.2 255.255.255.0
no keepalive
standby 2 ip 192.169.0.254
glbp 10 ip 192.169.0.253



Router 2


interface Ethernet1
ip address 192.169.0.3 255.255.255.0
no keepalive
standby 2 ip 192.169.0.254
standby 2 priority 150
standby 2 preempt
glbp 10 ip 192.169.0.253


 

Route maps with static NAT. (Question #10)

The command to configure a static NAT entry also allows you to specify a route map. For instance, you could have

ip nat inside source static 10.10.10.1 177.23.2.1 route-map TEST

The need for a route map for dynamic NAT is obvious. But when would a route map be useful for static NAT entries where the source address to be translated has already been explicitly specified?

This page is powered by Blogger. Isn't yours?