CCNP Certification / BCMSN Examination Tutorial: Starting out With HSRP
Defined in RFC 2281, HSRP is often a Cisco-proprietary protocol during which routers are place into an HSRP router group. Coupled with dynamic routing protocols and STP, HSRP is taken into account a superior-availability community service, because all 3 have an Virtually instant cutover to your secondary route when the primary route is unavailable.
One of many routers are going to be chosen as the key (“Active”, 안전놀이터 in HSRP terminology), and that Major will cope with the routing when the other routers are in standby, ready to take care of the load if the primary router results in being unavailable. On this manner, HSRP ensures a large network uptime, as it routes IP website traffic without counting on only one router.
The hosts employing HSRP for a gateway don’t know the particular IP or MAC addresses with the routers in the team. They’re communicating having a pseudorouter, a “virtual router” established via the HSRP configuration. This virtual router will have a virtual MAC and IP adddress at the same time.
The standby routers aren’t just going to be sitting there, while! By configuring numerous HSRP teams on only one interface, HSRP load balancing can be achieved.
Prior to we get to the more advanced HSRP configuration, we far better obtain a fundamental a person started out! We’ll be using a two-router topology listed here, and keep in mind that one particular or equally of those routers may be multilayer switches in addition. For relieve of examining, I’m planning to make reference to them only as routers.
R2 and R3 will both of those be configured to generally be in standby team five. The Digital router may have an IP tackle of 172.twelve.23.ten /24. All hosts in VLAN a hundred should use this tackle as their default gateway.
R2(config)#interface ethernet0
R2(config-if)#standby five ip 172.12.23.10
R3(config)#interface ethernet0
R3(config-if)#standby five ip 172.twelve.23.ten
The clearly show command for HSRP is show standby, and it’s the first command you must run even though configuring and troubleshooting HSRP. Allow’s run it on equally routers and Examine outcomes.
R2#display standby
Ethernet0 – Group 5
Regional point out is Standby, priority one hundred
Hellotime 3 sec, holdtime 10 sec
Following hello despatched in 0.776
Digital IP tackle is 172.twelve.23.10 configured
Energetic router is 172.twelve.23.3, priority a hundred expires in 9.568
Standby router is area
one state modifications, final point out modify 00:00:22
R3#display standby
Community point out is Active, precedence one hundred
Upcoming hello despatched in two.592
Active router is local
Standby router is 172.12.23.2 expires in 8.020
Digital mac tackle is 0000.0c07.ac05
2 state alterations, last point out change 00:02:08
We are able to see that R3 continues to be chosen given that the Active router (“local state is Lively”), the Digital router’s IP is 172.twelve.23.ten, and R2 is the standby router.
There are numerous HSRP values that you simply’ll require to change from time to time. Imagine if we would like R2 to get the Active router rather? Can we change the MAC deal with of the Digital router? I’ll respond to All those questions in the following part of this HSRP tutorial!