CCNP Certification / BCMSN Examination Tutorial: Getting Started With HSRP
Defined in RFC 2281, HSRP is often a Cisco-proprietary protocol wherein routers are put into an HSRP router group. As well as dynamic routing protocols and STP, HSRP is taken into account a superior-availability network service, considering that all 3 have an Practically speedy cutover to the secondary path when the main path is unavailable.
On the list of routers will probably be selected as the key (“Active”, in HSRP terminology), and that Key will tackle the routing even though one other routers are in standby, Prepared to deal with the load if the key router turns into unavailable. During this fashion, HSRP guarantees a substantial community uptime, because it routes IP site visitors with no counting on just one router.
The hosts using HSRP like a gateway don’t know the actual IP or MAC addresses from the routers in the group. They’re communicating with a pseudorouter, a “virtual router” created via the HSRP configuration. This virtual router will have a virtual MAC and IP adddress too.
The standby routers aren’t just gonna be sitting there, although! By configuring various HSRP teams on an individual interface, HSRP load balancing might be attained.
Prior to we get 토토검증 to the greater State-of-the-art HSRP configuration, we far better have a essential just one started out! We’ll be utilizing a two-router topology in this article, and Take into account that just one or both of those routers can be multilayer switches too. For simplicity of studying, I’m going to confer with them only as routers.
R2 and R3 will the two be configured being in standby team five. The virtual router will have an IP address of 172.12.23.ten /24. All hosts in VLAN a hundred need to use this deal with as their default gateway.
R2(config)#interface ethernet0
R2(config-if)#standby five ip 172.twelve.23.ten
R3(config)#interface ethernet0
R3(config-if)#standby 5 ip 172.twelve.23.ten
The present command for HSRP is demonstrate standby, and it’s the initial command you ought to operate whilst configuring and troubleshooting HSRP. Enable’s operate it on both equally routers and Assess outcomes.
R2#present standby
Ethernet0 – Group 5
Regional point out is Standby, precedence one hundred
Hellotime three sec, holdtime ten sec
Subsequent hi despatched in 0.776
Digital IP tackle is 172.twelve.23.10 configured
Active router is 172.twelve.23.3, precedence one hundred expires in nine.568
Standby router is regional
one condition changes, last state transform 00:00:22
R3#clearly show standby
Regional condition is Energetic, precedence 100
Future howdy despatched in 2.592
Lively router is nearby
Standby router is 172.twelve.23.two expires in eight.020
Digital mac handle is 0000.0c07.ac05
two point out changes, last condition transform 00:02:08
We will see that R3 has actually been picked since the Energetic router (“neighborhood state is Lively”), the Digital router’s IP is 172.12.23.ten, and R2 is the standby router.
There are numerous HSRP values that you simply’ll need to alter every now and then. Imagine if we wish R2 to become the Lively router rather? Can we alter the MAC deal with from the Digital router? I’ll answer Individuals concerns in the next part of the HSRP tutorial!