New Year Sale 2026! Hurry Up, Grab the Special Discount - Save 25% - Ends In 00:00:00 Coupon code: SAVE25
Welcome to Pass4Success

- Free Preparation Discussions
Mail Us support@pass4success.com
Location US
Mob_nav_barsMENU

Ericsson ECP-206 Exam - Topic 4 Question 25 Discussion

Actual exam question for Ericsson's ECP-206 exam
Question #: 25
Topic #: 4
[All ECP-206 Questions]

Which mismatched field would cause an IS-IS adjacency between two routers to fail?

Show Suggested Answer Hide Answer
Suggested Answer: A

MTU mismatch would cause an IS-IS adjacency between two routers to fail. MTU stands for maximum transmission unit, which is the maximum size of a packet that can be transmitted on a link. IS-IS hellos are padded to the full MTU size, partly to allow a router to implicitly communicate its MTU to its neighbors.If two routers have different MTUs on their interfaces, they will not be able to exchange hellos properly, and their adjacency will not form or will be dropped34. To solve this problem, the MTUs on both interfaces must be configured to match.

SEL, context, and SysID are not fields that would cause an IS-IS adjacency failure. SEL stands for selector, which is a one-octet field that identifies the network layer service to which a packet should be sent.For IS-IS routers, the SEL must always be 005.Context is not a field in IS-IS packets, but rather a term used to describe the scope of routing information in different levels or areas6. SysID stands for system identifier, which is a six-octet field that uniquely identifies a router within an area.SysID does not have to match between two routers for them to form an adjacency7.


by Tarra at Aug 28, 2024, 04:09 AM

Limited Time Offer

25%

Off

Get Premium ECP-206 Questions as Interactive Web-Based Practice Test or PDF

Contribute your Thoughts:

0/2000 characters
Submit Cancel
Gearldine
3 months ago
100% agree, MTU is the usual suspect here.
upvoted 0 times
...
Eveline
3 months ago
Wait, really? I didn't know MTU was that critical.
upvoted 0 times
...
Suzi
3 months ago
SEL mismatch can also mess things up!
upvoted 0 times
...
Elly
4 months ago
I thought it was SysID that caused problems?
upvoted 0 times
...
Deane
4 months ago
Definitely MTU, it's a common issue.
upvoted 0 times
...
Shanice
4 months ago
Context seems less likely to affect adjacency, but I could be wrong. I need to double-check my notes on that.
upvoted 0 times
...
Leonora
4 months ago
I practiced a similar question where SysID was mentioned, and I feel like that one is crucial for establishing adjacency.
upvoted 0 times
...
Mary
4 months ago
I think SEL might be important too, but I can't recall if it's a critical factor for adjacency.
upvoted 0 times
...
Remedios
5 months ago
I remember studying that MTU mismatches can definitely cause issues, but I'm not sure about the others.
upvoted 0 times
...
Karan
5 months ago
The context field seems like an interesting option, but I'm not as familiar with how that impacts IS-IS adjacency. I'll have to research that a bit more.
upvoted 0 times
...
Nancey
5 months ago
I'm pretty confident this has to do with the System ID (SysID) field. That's a key parameter for establishing IS-IS adjacency, right?
upvoted 0 times
...
Krystal
5 months ago
Hmm, this seems like a tricky one. I'll need to think through the different IS-IS adjacency requirements carefully.
upvoted 0 times
...
Tenesha
5 months ago
I'm a bit unsure on this one. Could it also be something like the MTU or SEL field? I'll have to review my notes to be sure.
upvoted 0 times
...
Dana
5 months ago
This seems like a classic high availability scenario. I'd go with option D and use an Auto Scaling group across two AZs, setting the minimum capacity to 4 to ensure the 60% availability is maintained. That way, the system can automatically scale up and down as needed.
upvoted 0 times
...
Markus
5 months ago
Okay, I've got this. The slope-policy and the WRED-policy are the two that will allow dynamic queue rate allocation when combined.
upvoted 0 times
...
Stephen
1 year ago
I think SysID is also important for identifying the router, so that could be a potential mismatch causing the adjacency to fail.
upvoted 0 times
...
Benedict
1 year ago
MTU all the way! I once had a colleague who thought changing the MTU would make the network 'go faster'. Needless to say, we had to roll back that change pretty quickly.
upvoted 0 times
Mose
1 year ago
B) SEL
upvoted 0 times
...
Emogene
1 year ago
Oh no, changing the MTU can definitely cause issues with IS-IS adjacencies.
upvoted 0 times
...
Casie
1 year ago
A) MTU
upvoted 0 times
...
...
Laurene
1 year ago
Gotta be the Context field. I mean, who even uses that anyway? Sounds like something straight out of a networking trivia game.
upvoted 0 times
Flo
1 year ago
Definitely, it's not a common field to come across in networking.
upvoted 0 times
...
Nana
1 year ago
Yeah, I agree. Context seems like the odd one out here.
upvoted 0 times
...
Wendell
1 year ago
D) SysID
upvoted 0 times
...
Ernie
1 year ago
C) Context
upvoted 0 times
...
Blair
1 year ago
B) SEL
upvoted 0 times
...
Annmarie
1 year ago
A) MTU
upvoted 0 times
...
...
Lenna
1 year ago
But MTU affects the maximum size of packets that can be transmitted, so it seems like a critical field to match.
upvoted 0 times
...
Lorrine
2 years ago
SysID, for sure. Can't have two routers with the same system ID, that's just asking for trouble. Although, I did once work with a team that thought changing the SysID was a good way to 'optimize' the network. Needless to say, that didn't end well.
upvoted 0 times
...
Hannah
2 years ago
I disagree, I believe it's Context that would cause the adjacency to fail.
upvoted 0 times
...
Florinda
2 years ago
Definitely the MTU! I learned that one the hard way during a network troubleshooting session. Reminds me of the time I accidentally set the MTU to 1400 on a link - instant connectivity loss!
upvoted 0 times
Wilda
1 year ago
B) SEL
upvoted 0 times
...
Elfrieda
1 year ago
Oh no, that must have been frustrating!
upvoted 0 times
...
Leatha
1 year ago
A) MTU
upvoted 0 times
...
...
Lenna
2 years ago
I think the mismatched field that would cause an IS-IS adjacency to fail is MTU.
upvoted 0 times
...

Save Cancel