CCNP Certification / BCMSN Test Tutorial: Starting out With HSRP
Defined in RFC 2281, HSRP is actually a Cisco-proprietary protocol through which routers are put into an HSRP router group. Along with dynamic routing protocols and STP, HSRP is considered a significant-availability network support, due to the fact all 3 have an Pretty much instant cutover to a secondary route when the main route is unavailable.
One of several routers will likely be chosen as the main (“Energetic”, in HSRP terminology), and that Main will deal with the routing although one other routers are in standby, Completely ready to handle the load if the key router will become unavailable. During this manner, HSRP guarantees a higher community uptime, since it routes IP traffic with no counting on one router.
The hosts using HSRP to be a gateway don’t know the particular IP or MAC addresses with the routers within the team. They’re communicating using a pseudorouter, a “Digital router” produced because of the HSRP configuration. This Digital router will likely have a virtual MAC and IP adddress as well.
The standby routers aren’t just going to be sitting there, nevertheless! By configuring many HSRP groups on only one interface, HSRP load balancing is usually obtained.
Before we reach the greater Highly developed HSRP configuration, we improved receive a basic one particular begun! We’ll be employing a two-router topology in this article, and keep in mind that one particular or both of those of those routers could be multilayer switches too. For relieve of looking through, I’m gonna consult with them only as routers.
R2 and R3 will both of those be configured for being in standby group 5. The virtual router will likely have an IP address of 172.12.23.ten /24. All hosts in VLAN 100 should really use this address 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 5 ip 172.12.23.10
The demonstrate command for HSRP is demonstrate standby, and it’s the 1st command you'll want to operate when configuring and troubleshooting HSRP. Enable’s run it on each routers and Assess success.
R2#display standby
Ethernet0 – Team 5
Neighborhood condition is 먹튀검증업체 Standby, priority one hundred
Hellotime three sec, holdtime ten sec
Following hello despatched in 0.776
Virtual IP handle is 172.twelve.23.10 configured
Lively router is 172.12.23.3, priority a hundred expires in 9.568
Standby router is community
one state alterations, last point out modify 00:00:22
R3#present standby
Community condition is Energetic, priority a hundred
Up coming hi despatched in two.592
Active router is regional
Standby router is 172.twelve.23.two expires in 8.020
Virtual mac tackle is 0000.0c07.ac05
2 point out improvements, previous point out change 00:02:08
We could see that R3 continues to be selected given that the Lively router (“neighborhood condition is Lively”), the virtual router’s IP is 172.twelve.23.10, and R2 is the standby router.
Usually there are some HSRP values that you just’ll require to vary every so often. Let's say we would like R2 to become the Lively router instead? Can we alter the MAC address with the virtual router? I’ll reply Individuals concerns in the following section of the HSRP tutorial!