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23

Besides VRRP not being proprietary, there are a few minor differences between the protocols as well: With HSRP, each interface must have an IP address that is separate from the HSRP group address. VRRP lets you share the Master's interface IP address. On Cisco devices, VRRP is configured to preempt by default, whereas HSRP is not configured to preempt by ...


9

HSRP 1) Cisco propriteray 2) 1 Active & 1 standby router & 1 or more listening routers 3) use virtual ip add as gateway 4) hello 3 sec & holddown timer 10 sec 5) we can enable preempt manually (standby 1 preempt) 6) multicast at:224.0.0.2 (ver1), multicast at:224.0.0.102 (ver2). Both versions use udp port 1985 VRRP 1) open standard (ietf) ...


9

GLBP doesn't use gratuituous ARP. When someone asks which MAC does the virtual IP have, the AVG will reply saying "This IP is at this MAC", using the field "Sender MAC Address", which is invisible to the switch's CAM table. The source address is still the AVG MAC. EDIT: I said it wrong. The IP address requested is actually the Sender, the Target address is ...


6

You forgot to use the standby 5 preempt command. It is also a good idea to set a preempt delay. Hot Standby Router Protocol (HSRP): Frequently Asked Questions: Q. Which HSRP router requires that I configure preempt? A. An HSRP-enabled router with preempt configured attempts to assume control as the active router when its Hot Standby priority is ...


6

What the ISP means is that as they make changes, you may lose connectivity for a time because the ARP table entries your router has with them will not match the changes it is making. If you reduce the ARP timeout, you reduce the time you may have lost connectivity. You really only need to change arp timeout on the interface used to connect to the ISP. ...


5

Cisco has many documents to explain such things. For example, Hot Standby Router Protocol (HSRP): Frequently Asked Questions: Q. If there is no priority configured for a standby group, what determines which router is active? A. The priority field is used to elect the active router and the standby router for the specific group. In the case of an equal ...


4

These are two completely independent protocols. VRRP doesn't interact with OSPF, or vice versa. VRRP will create a virtual gateway, and one router (layer-3 switch?) will be the primary and the other router will be the secondary which takes over if the primary router fails. This has nothing to do with the routing protocol. The real concern with an FHRP is ...


3

An HSRP group on an interface is an instance. Each layer-3 interface could have an HSRP group 1, but each is a different instance, and, indeed, are actually different HSRP groups, despite having the same number. The HSRP group is local to the interface, so HSRP group 1 on one interface is not the same HSRP group 1 on a different interface.. For example, you ...


3

FHRPs, like VRRP, and HSRP, don't load balance anything; that is not their purpose. The purpose of an FHRP is to give a virtual gateway, which can fail to a different physical router in the case of a primary router failure. The gateway is either statically configured on hosts, or assigned to the hosts by DHCP. Some people will also use the assigned gateway ...


3

VRRP is used to create a virtual router that can be made redundant by using two routers in a cluster. One router is active, the other is in standby. When the active router fails, the virtual router's IP and MAC addresses are taken over by the standby router. That way, you can create a failover scenario with next to no connectivity loss. Using NAT with ...


3

VRRP, and other FHRPs such as HSRP, allow you to have a default gateway configured on your hosts that does not really exist. One router will take over the virtual router IP and MAC addresses, and if that router fails, then another router that was in standby can take over the virtual addresses. This lets you have backup routers in case one router fails. Some ...


3

The individual routers' physical interfaces do not share the master router's IP address. Each router must have different addresses configured on the physical interface. What that statement means is that the virtual interface may be assigned to the IP address of one of the physical interfaces. The physical interface which shares its address with the virtual ...


3

HSRP is Cisco-proprietary. VRRP is not (RFC 5798). There are probably other nitty gritty technical differences, but that is the major one. And IIRC VRRP doesn't have the ability to do interface tracking, while HSRP does - might be wrong on this though. edit: RFC 5798 gives v6 support to VRRP. The original RFC was 2338.


3

The HSRP behavior is normal; that's how HSRP works. You don't say what kind of switch you are using, but most Cisco switches can change the CAM aging interval. They have something like: mac address-table aging-time <time> Some Cisco switches with different IOS versions may have the dashes different from this.


2

It's hard to say exactly what the question is. Maybe you should rephrase it, with something like : "Is fortinet implementation of VRRP RFC-Compliant?" The fact is the RFC3768 is obsoleted by RFC5798, where it is stated in section 3 : VRRP specifies an election protocol to provide the virtual router function described earlier. All protocol ...


2

I’ve never heard the term switch-back-delay, nor can I find anything referencing it on the internet or in RFC 5798. The you’re really looking for is Preemption Hold Time. This is the time a higher priority VRRP speaker will wait until preemption of the mastership role happens. There isn't a hold timer reference in the RFC, so that’s a vendor specific ...


2

The answer is actually on Wikipedia: Sender hardware address (SHA) Media address of the sender. In an ARP request this field is used to indicate the address of the host sending the request. In an ARP reply this field is used to indicate the address of the host that the request was looking for. (Not necessarily address of the host replying as ...


2

HSRP : 1) CISCO Proprietary 2) RFC 2281 3) Multicast group Ip: 224.0.0.2 V1 224.0.0.102 V2 4) Port No. UDP 1985 5) PREEMPT: By default disabled 6) Virtual Mac address: 0000.0c07.acxx xx = HSRP group id 7) Ipv6 Support 8) Router roll: 1 Active 1 Standby VRRP: 1) IEEE STANDARD 2) RFC 3768 3) Multicast group Ip 224.0.0.18 4) ...


2

Edited to reflect new information in the question: Based on your multiple edits which finally give the whole picture (I hope), you can try something like this, but using the switch stacking capability in the alternative configuration will give you a better solution. Your connection to the ISP will need to be on the same subnet as the ISP. SW1: track 3 ...


2

Yes, of course that is not only possible, but it is usually the case. Each VLAN will have at least one (possibly more) HSRP groups, even on the same interface. It used to be a common practice to set up an HSRP group for odd addresses to one primary router, and a different HSRP group on the same interface for the even addresses that uses the other router as ...


2

One thing I noticed is that you are not tracking the links to the firewall, and you have no way configured for VRRP to fail over to the other switch if a link goes down. You will fail over if the entire switch fails. You probably want the priority on the primary VRRP switch to be set at 105, and the backup as 100, then decrement by 10 if the link to the ...


2

in this topology, i should configure a HSRP group on interface 0/0/1(192.168.1.0 network) of router7 and router8, and configure another HSRP group on interface 0/0/0(172.24.0.0 network) of router7 and router8 to allow the connectivity between server2 and server3? HSRP is configured per interface, and the interface must be able to connect to the ...


2

An FRHP (First Hop Redundancy Protocol), like HSRP and VRRP, will present virtual IP and MAC addresses to the LAN, and the LAN hosts can be configured to use the virtual IP address for the LAN gateway. One real router will respond to the virtual addressing, and using preempt, the other real router can take over in the event of the failure of the first router....


1

Well I found an exact answer with documentation to match. The answer is 32. HSRP can be configured on 32 interfaces. (Documentation to provide an exact answer was what I had asked for, not various interpretations of the documentation I had already provided.) From here, page 34-4: HSRP Configuration Guidelines Follow these guidelines when configuring HSRP: ...


1

With a single group, they only provide resilience, the active router will service all traffic for the group, you are correct that you would need multiple groups to achieve crude load-balancing (although this is not a good solution), each group would have its own virtual IP to provide load-balancing, one router would be active for one group, and the other ...


1

Yes, Cisco supports VRRP. Cisco maintains many documents regarding this, e.g. First Hop Redundancy Protocols Configuration Guide, Cisco IOS Release 15M&T: Enabling VRRP SUMMARY STEPS enable configure terminal interface type number ip address ip-address mask vrrp group ip ip-address [secondary] end show vrrp [brief] | ...


1

Having both HSRP and VRRP on a router is fine, as long as they are configured on different interfaces, which seems to be the case. There are probably several things wrong with the way this is configured. For example, preempt in not used consistently (see interface GigabitEthernet0/0.4, ip address 1.1.4.3 255.255.255.0), and I would actually put a delay on ...


1

Your two devices cannot communicate over that VLAN, so they cannot exchange HSRP messages on that VLAN. Each comes up thinking it is the active router. One will remain the active router, and one will become the standby router when they fight it out with the messages between them on the VLAN. Make sure that you can get from one to the other over Vlan111. You ...


1

You can use VRRP, assuming your routers support it, but it requires at least two or three IP addresses in the same network. You need an address for each of the routers, and one address for the virtual address (some implementations of VRRP allow the virtual address to be the real address of one of the routers). The routers also need to be able to communicate ...


1

HSRP can provide first hop redundancy on your LAN. There are options to change the active router for things like router or link failure. Each outside interface needs its own IP address from the ISP. Each inside interface needs its own IP address plus one more for the virtual IP address.


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