CCNP Certification / BCMSN Test Tutorial: Getting Started With HSRP
Described in RFC 2281, HSRP is often a Cisco-proprietary protocol through which routers are place into an HSRP router team. In conjunction with dynamic routing protocols and STP, HSRP is considered a superior-availability community support, since all 3 have an Pretty much speedy cutover into a secondary route when the primary path is unavailable.
On the list of routers will probably be picked as the first (“Lively”, in HSRP terminology), and that primary will deal with the routing even though the other routers are in standby, ready to manage the load if the principal router will become unavailable. On this fashion, HSRP makes certain a large network uptime, as it routes IP website traffic without relying on an individual router.
The hosts making use of HSRP for a gateway don’t know the particular IP or MAC addresses of the routers in the group. They’re communicating that has a pseudorouter, a “Digital router” created from the HSRP configuration. This Digital router will have a virtual MAC and IP adddress in addition.
The standby routers aren’t just destined to be sitting down there, however! By configuring numerous HSRP groups on one interface, HSRP load balancing may be obtained.
Prior to we get to the greater Sophisticated HSRP configuration, we better get yourself a fundamental one particular started off! We’ll be using a two-router topology listed here, and Understand that one or each of such routers might be multilayer switches also. For relieve of reading through, I’m about to consult with them only as routers.
R2 and R3 will the two be configured being in standby group five. The Digital router should have an IP deal with of 172.12.23.ten /24. All hosts in VLAN 100 really should use this address as their default gateway.
R2(config)#interface ethernet0
R2(config-if)#standby five ip 172.12.23.ten
R3(config)#interface ethernet0
R3(config-if)#standby 5 ip 172.12.23.10
The present command for HSRP is demonstrate standby, and it’s the initial command you ought to operate even though configuring and troubleshooting HSRP. Permit’s operate it on the two routers and Assess final results.
R2#clearly show standby
Ethernet0 – Group 5
Neighborhood condition 먹튀사이트 is Standby, precedence one hundred
Hellotime three sec, holdtime ten sec
Following howdy sent in 0.776
Virtual IP handle is 172.12.23.ten configured
Active router is 172.12.23.three, priority a hundred expires in 9.568
Standby router is regional
1 state variations, past state modify 00:00:22
R3#clearly show standby
Community condition is Energetic, precedence a hundred
Upcoming howdy despatched in 2.592
Energetic router is neighborhood
Standby router is 172.12.23.2 expires in eight.020
Digital mac deal with is 0000.0c07.ac05
2 condition alterations, past condition adjust 00:02:08
We could see that R3 has become chosen as being the Lively router (“nearby state is Energetic”), the virtual router’s IP is 172.12.23.10, and R2 could be the standby router.
There are numerous HSRP values that you choose to’ll want to alter occasionally. What if we want R2 to get the Lively router instead? Can we alter the MAC tackle with the Digital router? I’ll solution All those thoughts in the following portion of the HSRP tutorial!