Hsrp

Hot Standby Router Protocol Hot Standby Router Protocol (HSRP) is a Cisco-proprietary First Hop Redundancy Protocol (FHRP). HSRP allows two physical gateways that are configured as part of the same HSRP group to share the same virtual gateway address. Network hosts residing on the same subnet as the gateways are configured with the virtual gateway IP address as their default gateway. You learn HSRP in our Related posts: You can learn We also have many CCNP level labs our in book 101 Labs – Cisco CCNP. While operational, the primary gateway forwards packets destined to the virtual gateway IP address of the HSRP group. In the event that the primary gateway fails, the secondary gateway assumes the role of primary and forwards all packets sent to the virtual gateway IP address. Figure 1 below illustrates the operation of HSRP in a network: Fig. 1. Hot Standby Router Protocol (HSRP) Operation Referencing Figure 1, HSRP is configured between the Layer 3 (Distribution Layer) switches, providing gateway redundancy for VLAN 10. The IP address assigned to the Switch Virtual Interface (SVI) on Layer 3 Switch 1 is 10.10.10.2/24, and the IP address assigned to the SVI on Layer 3 Switch 2 is 10.10.10.3/24. Both switches are configured as part of the same HSRP group and share the IP address of the virtual gateway, which is 10.10.10.1. Switch 1 has been configured with a priority of 105, while Switch 2 is using the default priority of 100. Because of the higher priority, Layer 3 Switch 1 ...

• Share on Twitter Share on Twitter • Share on Facebook Share on Facebook • Share on LinkedIn Share on LinkedIn • Share on Reddit Share on Reddit • Share via Email Share via Email Back in the day, the Cisco Press books only covered the Hot Standby Router Protocol (HSRP) topic in the professional-level track. When I did a quick search on CCNA books, I found out that they covered it in CCNA R&S ICND2 200-105 OCG* and the new CCNA 200-301 OCG, Vol 2*books. Both books, however, didn’t cover the security vulnerability of such minimal configuration. Thus, attacking HSRP is possible. This post contains affiliate links. If you use these links to buy something I may earn a commission. Full disclosure here. The books only discussed the theory behind it, the reason for using it, and implementation steps. While it’s all right to cover only the essentials, it is no longer sufficient to run HSRP without security because of how easy it is to attack it. In this article, I’m going to demonstrate how to perform an attack HSRP and protect it from such attacks. Related: VMware ESXi Home Lab – Intel NUC 10 (Frost Canyon) In this demo, I used EVE-NG and Kali Linux on my VMware ESXi home lab environment. If you’re looking for a small form factor server, you may want to consider Intel NUC. This NUC is my second one, and I am a fan of it! What is HSRP? HSRP is a Cisco proprietary protocol released around 1998, at least the RFC. It is one of the First Hop Redundancy Protocol (FHRP) supported in Cis...

Bias-Free Language The documentation set for this product strives to use bias-free language. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. Introduction This document describes how the Hot Standby Router Protocol (HSRP) functions and reviews its features. Prerequisites Requirements There are no specific requirements for this document. Components Used This document is not restricted to specific software and hardware versions. The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, ensure that you understand the potential impact of any command./p> Conventions For more information on document conventions, refer to HSRP Background and Operations One way to achieve near-100 percent network uptime is to use HSRP, which provides network redundancy for IP networks, and ensures that user traffic immediately and transparently recovers from first hop failures in network edge devices or access circuits. When two o...

• • • • • • Introduction Hot Standby Router Protocol (HSRP) provides redundancy for IP networks, ensuring that user traffic immediately and transparently recovers from first hop router failures. HSRP allows multiple routers on a single LAN to share a virtual IP and MAC address which is configured as the default gateway on the hosts. From the group of routers configured in an HSRP group, there is one router elected as the active router and another as a standby router. The active router assumes the role of forwarding packets sent to the virtual IP address. If the active router fails, the standby router takes over as the new active router. HSRP Configuration Overview: 1) Decide a virtual address to use for the HSRP address. This address must be in the same subnet that is assigned to the LAN interface where you want to run HSRP.This address is also referred to as the standby IP address. Each router in this group must define with the same virtual IP address using the standby [group-number] ip [Virtual ip-address] command. The standby group number= The default is 0. The group number range is from 0 to 255 for HSRP version 1 and from 0 to 4095 for HSRP version 2. If you are configuring HSRP on VLAN trunks, each VLAN or Ethernet sub interface must be in a different standby group. 2) Decide which router is to be the primary router. This can be accomplished with the standby [group-number] priority [priority] commands. Priority=this range is from 1 to 255, where 1 denotes the lowest ...

What is the HSRP? A default gateway router connects a network's local subnet to a remote subnet of the same network or another network. For backup, if an administrator wants to configure more than one default gateway router, the administrator needs to configure an FHRP protocol. FHRP is a family of protocols that provide a default gateway router redundancy. To learn more about FHRP, you can check the following tutorial. HSRP (Hot Standby Router Protocol) is a member of the FHRP family. It is a Cisco proprietary protocol. It works only on Cisco routers. It allows one router to automatically takes over if another fails. In other words, it provides a gateway router redundancy by automatically replacing a failed gateway router with a functional gateway router. Basic concepts of HSRP HSRP uses a simple and straightforward concept. This concept is known as an active/passive (standby) concept. The following steps describe this concept. • Form a group of all available devices. • Select a device as the main device. • Keep only the main device in the active state. • Put all other devices in the passive state or standby state. • If the main device fails, select a passive device from the available passive devices and make it an active device by changing its state to active. Before we explore this concept in more detail, let's briefly discuss HSRP terminology. HSRP Terminology HSRP uses the following terminology. HSRP group / Standby group HSRP is a group of all gateway routers. It inc...

This is the second of a two-part series on First Hop Redundancy Protocols (FHRP). In This article (Part 2) will compare HSRP to Virtual Router Redundancy Protocol (VRRP) and look at optional features in both. Similarities and Differences between HSRP and VRRP In Figure 1 below, you can see a comparison between the most common FHRPs. HSRP was created by Cisco, and VRRP is a standard (RFC). However, they both work in a similar way. HSRP v2 and VRRP support IPv4 and IPv6 but, for the purpose of simplicity, this article will focus on IPv4 and the Cisco IOS. Figure 1: Comparisons between HSRP v1, HSRP v2 and VRRP Let’s Begin with a Recap of FHRPs In order to understand the differences between HSRP and VRRP, let’s first recap the terminology and basic configuration of FHRPs A brief recap of FHRP: Endpoints (PCs, laptops, etc.) typically connect to the Access layer and the Servers are typically located in another subnet in the data center, reachable via the Distribution and Core network. FHRPs Create Redundant Paths from Endpoints to all other Subnets FHRPs are configured on the Layer 3 interface that connects down toward the endpoints at the access layer. Because a Multi-Layer Switch (MLS) is most typically used at the enterprise distribution layer, the Layer 3 interface that connects toward the endpoints is a Switch Virtual Interface (SVI). In figure 2, the SVI is “interface VLAN 2.” The only command required to enable HSRP: (config-if)# standby # ip x.x.x.x where # = group num...

Hot Standby Routing Protocol or HSRP, is a Cisco proprietary protocol that allows two or more routers to work together to represent a single IP address for a particular network. HSRP, as well as Virtual Route Redundancy Protocol (VRRP) are considered high-availability network services that allow for almost immediate fail over to a secondary interface when the primary interface becomes unavailable. The HSRP configuration can be tricky at times, so this article will cover the fundamental points also presenting a GNS3 lab. HSRP is one of the so called FHRP or “First Hop Redundancy Protocols”. You can read more about FHRP HSRP is a fairly simple concept that works by having one router within an HSRP group be selected as the primary, or active router. That primary will handle all routing requests while the other routers within the HSRP group simply wait in a standby state. These standby routers remain ready to take on all of the traffic load if the primary router becomes unavailable. In this scenario, HSRP provides high network availability since it routes IP traffic without depending on a single router. To really dig into the Nitty Gritty of HSRP, check out The hosts that use the HSRP address as a gateway never know the actual physical IP or MAC address of the routers in the group. Only the virtual IP address that was created within the HSRP configuration along with a virtual MAC address is known to other hosts on the network. Basic HSRP Configuration Before we discuss more ad...