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25

EIGRP is now an IETF draft so it's no longer proprietary. See http://tools.ietf.org/html/draft-savage-eigrp-01 If we look at EIGRP with default settings and OSPF with default settings and there are multiple loop free paths to a destination then EIGRP will converge much faster because it keeps what are called feasible successors in it's topology database. ...


17

I really don't like how Cisco crippled EIGRP in the ipbase image... at a minimum, you should get some kind of warning that your configuration won't work, but they haven't done that either. As you discovered, eigrp stub prevents EIGRP from advertising downstream routes from the switches connected to your distribution. You can trick EIGRP into advertising ...


14

You can read about the finer workings of these protocols for yourself, they are thoroughly documented on the Internet and it's a doddle to find information on them. From a practicle perspective I would say that in the case of EIGRP vs OSPF, OSPF always wins for the following reasons: Convergence Speed: Everyone always mentioned that EIGRP is faster than ...


12

You can inject static routes into EIGRP two ways: The 'network' command 'redistribute static' You only need one or the other; here you've used both. It seems that the redistribution command takes precedence over the network command so the route is appearing as static routes. Remove 'redistribute static' and the route should appear as internal.


12

Pete said: I can't think of a situation where you would need this. I just wanted to know what the logic was that makes this an explicit check in these routing protocols. Short answer Routing protocols are some of the most fundamental building blocks on the internet; we need them to be very reliable in every possible case. It does no good to bring up an ...


10

All routing protocols try to avoid a loop topology. If there is a routing loop, data is not getting to the destination. If the path from source to destination is A -> B -> C -> D, but there is a loop between B and C, data will never reach D.


9

The "network" command is not responsible for summarizing routes. In EIGRP, this command merely enables the EIGRP process on all matched interfaces. You should use the ip summary-address command on all interfaces on which you wish to advertise a summary. What the "network" command does is define a range of addresses that enables EIGRP on all interfaces ...


9

Your 4507 comes with an evaluation license that will let you run enterprise services for 60 days. You can activate the eval with the "license boot level entservices" command. Note this requires a reload of the switch. This will buy you some time while you purchase a permanent license.


9

Yes, that works fine. R1#sh run | s eigrp router eigrp 100 network 123.123.123.0 0.0.0.255 no auto-summary neighbor 123.123.123.3 FastEthernet0/0 neighbor 123.123.123.2 FastEthernet0/0 R1#sh ip eigrp nei IP-EIGRP neighbors for process 100 H Address Interface Hold Uptime SRTT RTO Q Seq ...


9

Since the summarized route means that a router advertising it has knowledge of the individual routes within the summarized prefix, it is more trustworthy than the same (summarized) prefix being advertised as an individual route without the knowledge of the individual routes which make up the summary. This doesn't mean that the summarized route is more ...


7

Any metric manipulation I've ever seen has been via offset-lists. This allows very fine-grained control over the metric, and removes the need to calculate metric differences based on different interface delays. Note that offset-lists have the added benefit of being applied (optionally) per-interface. So you can essentially do everything that a delay ...


7

I emailed Russ White (ex-Cisco employee / EIGRP specialist from the routing protocols deployment team), and this was his answer: If you think about the way a TCP stack works, you have some sort of switching process that accepts packets, and stuffs them onto a "forme" queue. That queue is processed by IP -- but how does IP know what process to hand ...


6

Your AS numbers need to match. Change either switch2 to router eigrp 1 or change switch1 to router eigrp 2 and reimplement the routing configuration on the device that is changed.


6

ip summary-address eigrp 172.16.0.0 255.255.252.0 Configure this on the intefaces facing the neighbor(s) you want to advertise the summary route.


6

You sound like you are looking for distribute-list. Have a look here for the command reference http://www.cisco.com/c/en/us/td/docs/ios/12_2/iproute/command/reference/fiprrp_r/1rfeigrp.html#wp1030208 Here is what you want, i think (not tested): access-list 1 deny 10.80.1.12 access-list 1 permit any router eigrp 1 network 10.0.0.0 distribute-list 1 out ...


6

By default EIGRP uses a classful network, meaning that it assumes that an address in the class A range with have an 8-bit subnet mask. There is no automatic process of checking other than the assumption that if you do not specify the subnet mask in wildcard mask format ( host mask ) then you want to use the default subnet mask for the IP range you've ...


6

You have the 10.0.0.0/8 and 172.16.0.0/16 networks defined on both the middle and right routers. Using auto-summary on both makes each think they own those whole summarized networks, so they will not send any traffic in those networks toward the other router. Using no auto-summary will allow each router to understand the more specific routes of each router.


6

The AD of the EIGRP summary route is 5 only on the router that has the summary route configured. When the summary is advertised to other routers it has an AD of 90. The reason for the low AD is to insure that the summary route (to nul0) is preferred to prevent routing loops.


5

In practice what is more commonly used out of those two options (delay/Offset-lists) Use whatever suits your requirements. delay is an interface-level command and gives you control over the delay on a specific interface offset-list is a protocol-level command that could change metrics for the whole EIGRP process. Thus, if it's me and I want to change ...


5

Creating a static route for "10.100.00.0/23" and redistributing it to EIGRP should do the trick. The static route would lift it into the routing table and the redistribution of static routs will announce the route to the EIGRP neighbors.


5

Create network statements with subnet masks for each interface you do want to advertise and exclude the interface you don't want to advertise. For example, if you have int gi 1/1 ip address 10.1.1.1 255.255.255.0 ! int gi 1/2 ip address 10.1.2.1 255.255.255.0 ! int gi 1/3 ip address 10.1.3.1 255.255.255.0 if you don't want to advertise 10.1.2.0 router ...


5

Since Cisco controls the EIGRP spec, they automatically provide additional information to BGP when EIGRP is advertised/redistributed into an MPLS VPN. This excerpt from Cisco's MPLS VPN support for EIGRP page gives the following details (emphasis mine): EIGRP Connectivity Between VPN Client Sites over a Service Provider Backbone In Figure 1, the EIGRP ...


5

According to the OSPF RFC 2328 (10.6): If the Interface MTU field in the Database Description packet indicates an IP datagram size that is larger than the router can accept on the receiving interface without fragmentation, the Database Description packet is rejected. The simple answer is that the standard was designed to just drop datagrams which ...


5

It's a little complex, and also platform specific in some cases. The most general answer is that the bandwidth statement is used as an input to the EIGRP routing protocol. There are also cases where the bandwidth command can be applied on a main or subinterface and impact QoS calculations. In general, unless you're running EIGRP and specifically need it, ...


5

There are philosophical differences in the design of OSPF and EIGRP and they are reflected in the protocol operation. For example, OSPF relies on a strict hierarchy/star topology to prevent loops. EIGRP uses the concept of successors for loop prevention, and this allows for more flexible topologies (not always a good thing). EDIT: OSPF and EIGRP stubs ...


5

Will ospf and eigrp share the 10 network on the right to their neighbors? As per my understanding link state protocols like ospf do so while eigrp being a distance vector protocol will share only one of the routes, but this case let's say both the routes are exactly same, how will this be handled then? By default, the router will install the ...


5

There is a command made for such checking. Use: show ip eigrp events


5

You have to put your interfaces into vrf 4. interface fa 2/0 ip vrf forwarding 4 An interface can only be in one vrf. Otherwise, how would the router know which interface to use? If you don't specify a vrf, the interface is put into the global table. But your EIGRP process is configured to use vrf 4.


5

That is because Cisco determines the AD used by its devices, and EIGRP is a Cisco protocol, so Cisco decided to make EIGRP have a lower AD than other protocols. Each vendor determines the relative reliability of protocols for its equipment; there is no outside standard for this. Some vendors may not even have an AD equivalent. According to Cisco default ...


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