CCNP Certification / BCMSN Examination Tutorial: Getting Started With HSRP
Described in RFC 2281, HSRP is a Cisco-proprietary protocol wherein routers are put into an HSRP router team. Together with dynamic routing protocols and STP, HSRP is considered a large-availability network support, since all 3 have an Pretty much rapid cutover to the secondary route when the principal path is unavailable.
Among the list of routers might be selected as the key (“Active”, in HSRP terminology), Which Main will take care of the routing when one other routers are in standby, Completely ready to handle the load if the principal router will become unavailable. In this particular style, HSRP guarantees a higher community uptime, because it routes IP website traffic without having counting on only one router.
The hosts utilizing HSRP as being a gateway don’t know the particular IP or MAC addresses of the routers from the team. They’re communicating using a pseudorouter, a “Digital router” produced with the HSRP configuration. This Digital router should have a virtual MAC and IP adddress likewise.
The standby routers aren’t just gonna be sitting there, even though! By configuring several HSRP groups on an individual interface, HSRP load balancing may be obtained.
Prior to we reach the greater Sophisticated HSRP configuration, we superior get a basic a single began! We’ll be using a two-router topology right here, and Understand that one or each of these routers can be multilayer switches also. For simplicity of reading through, I’m going to refer to them only as routers.
R2 and R3 will each be configured being in standby group 5. The virtual router should have an IP deal with of 172.12.23.ten /24. All hosts in VLAN a hundred must use this handle as their default gateway.
R2(config)#interface ethernet0
R2(config-if)#standby 5 ip 172.12.23.10
R3(config)#interface ethernet0
R3(config-if)#standby five ip 172.12.23.ten
The display command for HSRP is clearly show standby, and it’s the main command you need to operate when configuring and troubleshooting HSRP. Permit’s operate it on both equally routers and Look at benefits.
R2#display standby
Ethernet0 – Group 5
Local point out is Standby, priority 100
Hellotime 3 sec, holdtime 10 sec
Up coming hello despatched in 0.776
Digital IP deal with is 172.12.23.ten configured
Energetic router is 172.twelve.23.three, priority a hundred expires in 9.568
Standby router is community
1 state changes, past state adjust 00:00:22
R3#present standby
Community state is Energetic, precedence a hundred
Future hi there despatched in two.592
Active router is area
Standby router is 172.twelve.23.two expires in 8.020
Virtual mac address is 0000.0c07.ac05
2 state modifications, past state change 00:02:08
We can see that R3 has long been picked because the Energetic router (“local point out is Energetic”), the virtual router’s IP is 172.12.23.ten, and R2 is definitely the standby 먹튀사이트 router.
There are numerous HSRP values that you’ll want to change on occasion. Let's say we would like R2 being the Lively router as an alternative? Can we change the MAC deal with of the virtual router? I’ll respond to Those people questions in another section of the HSRP tutorial!
