Questions tagged [eigrp]
Use this tag for questions about Cisco's EIGRP - Enhanced Interior Gateway Routing Protocol.
104
questions
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2answers
53 views
EIGRP advertising of routes for other networks behind us
Continuing my expedition in to trying to learn EIGRP and other routing techniques in GNS3, I now have another theoretical network, depicted below:
Everything in the red area is a mystery. We do not ...
0
votes
2answers
47 views
EIGRP route redundancy in a ring topology
Within GNS3, I am attempting to configure five Cisco 3660 routers in a ring topology with EIGRP, as an early exercise to try and learn how to use EIGRP:
These routers and virtual PCs are configured ...
0
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1answer
142 views
EIGRP to BGP to EIGRP
I would like to ask if it is possible to implement eigrp routing sent through bgp?
I wanted to route from PC-1 to PC-2 using EIGRP. The connection between all of the three routers are through BGP ...
0
votes
2answers
224 views
If EIGRP is designed to work within same autonomous system, why it has concept of multiple ASN?
EIGRP is a CISCO proprietary protocol and a type of Interior Gateway Protocol, which replaced now obsolete Interior Gateway Routing Protocol. This protocol like every other interior routing protocol, ...
1
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1answer
51 views
Filter tagged route to downstream routers
I'd like to filter a redistributed route from EIGRP into OSPF to all routers in AREA2 and AREA34. I have tagged the route 10.90.100.0/24 with tag 90 at the Tampa router where its redistributed into ...
2
votes
1answer
49 views
How to check the route table on a neighboring router?
I have a router in a network, which use to show list of routes in the route table.
Using the command-
show ip eigrp topology
I see some of the routes are removed after sometime, which were advertised ...
0
votes
1answer
133 views
EIGRP Holding Time Expire on VLAN Interfaces
I configure 2 Layer 3 Switches with VLANs and EIGRP route.
But it always return a message like this :
%DUAL-5-NBRCHANGE: IP-EIGRP 2019: Neighbor 192.168.20.253 (Vlan20) is down: holding time expired
...
0
votes
0answers
16 views
RTO timer in EIGRP
Does EIGRP function like this - A packet is sent and the sender waits for acknowledgement. If it gets an acknowledgment, then it updates SRTT timer along with Sequence Number. If it doesn’t get any ...
1
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1answer
30 views
Why do we need EIGRP AS numbers when we have EIGRP RID?
I understand that the EIGRP routers need to have the same AS number to peer with each other. But why can't we just use EIGRP Router ID?
2
votes
2answers
130 views
How to ping from PC on EIGRP area to PC on OSPF area without middle router?
This is my topology.
And I can send a package to every router and PC within the colored area, how can I ping from a PC on EIGRP area to a PC on the OSPF area? I heard about default route but I saw it ...
2
votes
0answers
45 views
EIGRP Adjacency Table
From Cisco IP Routing by Alex Zinin
According to this figure Adjacency Table gets messages from DUAL module also.As far as I know, Adjacency Table is populated only because of Hello packets exchanged ...
0
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1answer
54 views
Packet Tracer 7.2.1 does not support eigrp for ipv6
I'm trying to enable eigrp for ipv6 in packet tracer but is seems to only have ospf and rip for ipv6.
Is this a recent limitation?
3
votes
1answer
197 views
EIGRP unequal load balancing, variance command
Is correct to say that the value inserted in the variance command, lets say the value of "2" on a route that has a cost of, lets say "100", will unequally load balance all routes up to a cost of 200 ?
...
3
votes
1answer
98 views
EIGRP Auto-summary
One more question about EIGRP,
EIGRP auto-summary what is the impact on the network ? i was reading about but it was not clear for me.
And why is it a good Cisco practice to be disabled ?
I am ...
1
vote
1answer
73 views
EIGRP metric claculation
I have a question regarding the EIGRP metric system.
so if K1 is the Bandwidth and formula is :
(K1 * BW + ((K2 * BW) / (256 - LOAD)) + K3 * DELAY ) * (K5 / (RELIABILITY + K4)
Whats is BW and ...
4
votes
2answers
387 views
Why does EIGRP aim to be loop free?
As far as I understand:
EIGRP is a routing protocol and handles IP packets. IP packets are outfitted with the TTL field and thus, do not loop indefinitely like layer 2 frames do.
Why does EIGRP try ...
1
vote
1answer
91 views
Cisco numeric EIGRP routing IP summarizing and routing
I have 2 routers connected via Serial 0/0/0 both running EIGRP with an ASN of 65000, and i want to advertise and summarize the interfaces, being just my loopbacks, and set the loopbacks as passive. ...
1
vote
1answer
1k views
Is it possible to remove/block a EIGRP neighbors connection via Switch?
I have a 4 routers that connected each other via an multilayer switch. Is it possible to remove/block an EIGRP neighbors via Switch?
For example, I have a topology like this :
I wanted to remove ...
1
vote
2answers
398 views
EIGRP Routing Issues
I had an issues about EIGRP. But first, here's the topology :
I've done EIGRP Routing, but it's kinda strange. PC0 -> PC1 is able to ping, PC3 -> PC2 is able to ping. But, I can't ping PC0 -> PC2, ...
2
votes
1answer
72 views
Why Static route (AD=150) and EIGRP route coexist under “show ip route”?
pic1 is topology
pic2 is routing table. EIGRP is enabled with auto summary, why there is a static router (AD=150)?
2
votes
1answer
428 views
EIGRP authentication on GRE tunnel interface?
I want to implement authentication on EIGRP updates.
Can I enable EIGRP authentication on a GRE tunnel interface instead of physical interface?
4
votes
1answer
972 views
Why does EIGRP have lower Administrative distance than OSPF?
I have given the following network diagram and been told that,
Since EIGRP has a better (lower) administrative distance than OSPF, the router on the far left will use the EIGRP path and publish ...
4
votes
1answer
61 views
Filter routes based on interface
In EIGRP is there a way to filter routes entering from a specific interface?
The intent is to protect the network core's routing table from receiving misconfigured or maliciously-inserted routes from ...
3
votes
2answers
333 views
Cannot see the differende between distance-vector and link-state
At link-state routing protocols each router advertises every link he knows about to the next router, which again advertises his links and so on until every router knows all links in his area. So every ...
1
vote
2answers
804 views
Will an EIGRP route be chosen over an OSPF route regardless of metrics?
I am sure this has been asked SOMEWHERE but I can't find it anywhere.
Question is simple: Will R1 chose the EIGRP route to R4 over the OSPF route, even though the OSPF route is clearly the better ...
1
vote
1answer
59 views
EIGRP manual summarization prevent dual query
In EIGRP, manual summarization will prevent/ limit dual query. Is it true ?
How can we limit the dual query by introducing manual summary ?
1
vote
2answers
1k views
BGP update source basics
I have the following test lab:
The configuration of 'King' is:
King#sho ip int bri
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 192....
3
votes
2answers
735 views
No passive-interface error
I'm trying to nest some EIGRP configurations on a router in GNS3.
I'm trying to connect the EIGRP 2801 in SW01 to RTR-01 and EIGRP 2864 to RTR-02 when I do.
When I put no passive-interface ...
3
votes
2answers
103 views
EIGRP neighbors discovering process
Quick question regarding EIGRP, as far I know, EIGRP has two tables: neighbors, and topology, and the router has its routing table obtained with DUAL algorithm applied to the topology table.
...
3
votes
2answers
416 views
EIGRP failover - how do i verify it happened?
I have 2 links to a destination and EIGRP was setup. The faster link is the successor and the slower link is the feasible successor.
Switch1#show ip eigrp topology 192.168.1.0
EIGRP-IPv4 Topology ...
0
votes
1answer
190 views
How does Cisco router know the sum of delays in eigrp?
I know one can use sh ip route command example below,
(r1) s2/0 -- s2/0 (r3) -- lo0 (r3)
so the delay from r1 to r3 lo0 would be sum of delay on s2/0 and delay on lo0 on r3.
it's easy for a ...
1
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1answer
391 views
c5915 DMVPN Spoke ISP Failover- Single Hub
I have a mobile application that utilizes cellular and satcom services to form a VPN connection to our hub. In the current configuration, failover works based on the ip hello-interval eigrp 1 15, ip ...
1
vote
1answer
45 views
Why does EIGRP not use Feasible Distance to determine the feasible successor
For EIGRP to determine a successor (best route), it uses the route with the lowest number of Feasible Distance(FD).
And to determine the feasible successor (which is the backup route or the next best ...
1
vote
1answer
2k views
When do we need metric calculations when redistribute EIGRP to OSPF and vice versa?
I am a newbie, and I'm curious. When do we need to calculate metrics on redistributing EIGRP to OSPF and vice versa. My practice use Cisco, type a command redistribute EIGRP 1 metric ... I'm confused. ...
2
votes
3answers
3k views
How do OSPF and EIGRP deal with 2 exactly same routes?
If you refer this diagram,
Will ospf and eigrp share the 10 network on the right to their neighbors?
I am asking the question in two separate scenarios using a single protocol at a time and not ...
1
vote
2answers
882 views
Preventing Load balancing in EIGRP
In a recent project, I have been told to consider four Hubs (two in HQ, and two in DR), where each branch will have EIGRP neighborships with all four, as part of a DMVPN based WAN. I have tested this ...
1
vote
2answers
2k views
BGP problems, cannot ping
I'm beginner, and I have problems with BGP. I don't really understand why it doesn't work correctly.
This is my topology:
I need to ping from R8 to R10.
This is the configuration of R8:
!
!
...
1
vote
1answer
507 views
A question about the router ID for EIGRP
If I configure a loopback interface and then set a router id by typing, eigrp router-id 10.0.0.1, for example, and the router protocol is EIGRP, what will be the accurate id for this router if the ID ...
1
vote
1answer
279 views
Handling multiple redundant Metro Ethernet circuits in one location
We have recently signed up for Metro Ethernet for our main campus and 8 branches. It's a "mesh" with the carrier providing a virtual layer-2 switch in the cloud. I have a Cisco router at each site ...
1
vote
1answer
116 views
EIGRP protocol convergence
When EIGRP loses Successor route and transfers to Feasible Successor route does it calculate another Feasible Successor right away? So the first Feasible Successor becomes the Successor and new FS is ...
2
votes
1answer
90 views
Adding 2nd EIGRP route to Data Center
I am adding a 2nd layer 3 link between data centers using EIGRP. I want the remote sites to continue to use the 100 Mb to routes that are in Data Center 2 (unless the link is down).
If I'm correct ...
2
votes
1answer
174 views
Difference in convergence time IPv4 vs IPv6
Using protocols like RIP, OSPF and EIGRP, would IPv6 converge faster in smaller network like 4 routers?
Would it differ in bigger networks?
1
vote
2answers
1k views
EIGRP neighbor problem
Why is R1 giving these error messages?
IP-EIGRP(Default-IP-Routing-Table:400): Neighbor 192.168.2.1 not on common subnet for FastEthernet1/0
IP-EIGRP(Default-IP-Routing-Table:400): Neighbor 192.168....
3
votes
4answers
1k views
Choosing a routing protocol
I have always wondered what causes an network engineer to pick EIGRP or OSPF over the other. Obviously OSPF is opened standard so can be used in a multi-vendor environment. If all equipment was cisco, ...
1
vote
2answers
5k views
How to connect different networks based on vlans using layer 3 switches and router?
This is a simplified version of my network diagram. How do I make both network speak to each other?
I'm confused because earlier I used routers and switches, and I connected them using OSPF or EIGRP....
2
votes
1answer
56 views
How to use network correctly on router protocols?
I was watching a video talking about EIGRP protocol and got confused in the network part.
The part of the topology was:
R1 e0/1, with IP of 10.1.12.1/24
connected on
R2 e0/0, with IP of 10.1.12.2/24
...
0
votes
1answer
856 views
Discontiguous Addresses in IP Subnets
What are the reasons for using only contiguous addresses in subnets? Will something malfunction if we use dis contiguous IP addresses?
I am aware that RIP and IGRP will auto-summarize which results ...
4
votes
0answers
443 views
Dual-Hub DMVPN Outage
Our backup links have always utilized a GRE tunnel based VPN to a hub. Recently we installed a second hub and migrated the primary links to GRE tunnel based VPN with EIGRP to handle routing between ...
1
vote
1answer
65 views
EIGRP delay summarization?
Could you please explain why when sending EIGR updates only delay of incomig interfaces are summarized and delay of outgoing interfaces is not considered. Please see picture below:
1
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1answer
266 views
Apparently variance is not working for EIGRP ..what am I missing?
Here is what my router is reporting. I set the variance to 100 just to see what is going on. This is using classic configuration and the RD for the two alternate links is 537600. If I multiply the FS (...
