Goddess that I am, I actually do have a subnetting question

Do we always assume that subnet zero is not configured to be allowed for the CCNA? I've noticed some practice tests in which the "correct" answer is to divide a class B into /17s or a class C into /25s...do we just assume for these and these only that "no ip subnet zero" is configured? Or on the actual tests, do we not see these type of questions?

Thank you!

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Comments

peanutnoggin

Unfortunately,

No one could directly answer that question regarding the CCNA because that would be a violation of the NDA. What I can tell you is... you will receive specific instructions from the exam regarding each question.

-Peanut

SubnettingGoddess

Thank you peanut...I will just wait for the test and not worry over it then.

peanutnoggin

SubnettingGoddess wrote: »

Thank you peanut...I will just wait for the test and not worry over it then.

No worries... looking at your experience in your other post, I believe you have the knowledge to discern the answer if you're in that situation... Good luck with your studies.

-Peanut

bermovick

Actually the study guides pretty much tell you that unless it states otherwise, you can assume the zero subnets are valid.

Zartanasaurus

bermovick wrote: »

Actually the study guides pretty much tell you that unless it states otherwise, you can assume the zero subnets are valid.

Was just about to post this.

SubnettingGoddess

Thanks...as you can probably tell, I skipped the subnetting section of my book.

Guess it would not hurt to read it in case of any more tidbits like this.

rogue2shadow

bermovick wrote: »

Actually the study guides pretty much tell you that unless it states otherwise, you can assume the zero subnets are valid.

Agreed. My network academy professor told us the same. Cisco exams are very straight-forward and they will tell you every bit of information you need to know for exactly what they want done. When it comes test time you'll see its literally "you either know it or you don't".

Turgon

SubnettingGoddess wrote: »

Thanks...as you can probably tell, I skipped the subnetting section of my book. Guess it would not hurt to read it in case of any more tidbits like this.

You are aware of ip subnet zero which is half the battle so that's a good thing. But yes, put plenty of time in on the subnetting exercises. It will only assist you come test time!

tech-airman

SubnettingGoddess wrote: »

Do we always assume that subnet zero is not configured to be allowed for the CCNA? I've noticed some practice tests in which the "correct" answer is to divide a class B into /17s or a class C into /25s...do we just assume for these and these only that "no ip subnet zero" is configured? Or on the actual tests, do we not see these type of questions?

Thank you!

SubnettingGoddess,

I think a relevant question is why is there this subnet zero issue? Have you started studying routing protocols, for example RIP verson 1?

SubnettingGoddess

tech-airman wrote: »

SubnettingGoddess,

I think a relevant question is why is there this subnet zero issue? Have you started studying routing protocols, for example RIP verson 1?

It's only an issue in sample questions that do not make clear whether or not it's configured. But I have some comfort now that when I face the actual exam, it will be clear whether or not it is.

jovan88

Cisco usually do a good job on exam questions and I doubt they will purposely screw anyone over on a subnet 0 question

tech-airman

SubnettingGoddess wrote: »

It's only an issue in sample questions that do not make clear whether or not it's configured. But I have some comfort now that when I face the actual exam, it will be clear whether or not it is.

SubnettingGoddess,

Do you know about the destination IP address field and source IP address field in an IP packet?

SubnettingGoddess

tech-airman wrote: »

SubnettingGoddess,

Do you know about the destination IP address field and source IP address field in an IP packet?

What about them?

tha_dub

Your best bet for an issue like this is assume current cisco defaults if you have no other info. They've defaulted to use the zero subnets in IOS for quite a long time now so if I wasn't given info one way or the other....

Also this applies in one other place I can think of off the top but I'm sure there are more. Most (if not all) 2950 switch's default to dynamic desirable for trunking which will automatically trunk with another switch if connected. 2960 switches default to dynamic auto which means 2 connected 2960's will not trunk without further config.

tech-airman

SubnettingGoddess wrote: »

What about them?

SubnettingGoddess,

Does the destination IP address field of an IP packet include a subnet mask?

networker050184

tech-airman,

What is your major malfunction?

fly351

tech-airman wrote: »

SubnettingGoddess,

Does the destination IP address field of an IP packet include a subnet mask?

I would also like to know what you are getting at. The fact is, she is trying to learn the functions of a router and when / if it is applicable.

SubnettingGoddess

phoeneous wrote: »

Do 20 of these a day:

subnettingquestions.com - Free Subnetting Questions and Answers Randomly Generated Online

Thank you phoeneous...like my certs section says, it is actually the one thing I am very good at. I just wasn't sure since with the study material I am using, sometimes you have to assume it's enabled and sometimes not...nice to know that should not be an issue on the actual exam.

SubnettingGoddess

tech-airman wrote: »

SubnettingGoddess,

Does the destination IP address field of an IP packet include a subnet mask?

Wow tech-airman, you are the one with a CCNA and you'd ask such a newb question?

I'd think with your l33t skillz, you'd know it does not.

SubnettingGoddess

phoeneous wrote: »

He does know, he was asking to see if you know.

Yes, I know. Was just rather puzzled that he was quizzing me out of the blue.

SubnettingGoddess

But anyway, if we're playing this game, my turn!

You have a Cisco 7300 series router at your border. It randomly *poof* loses its serial interface configurations. Not that they go down. They are simply gone from RAM. Only a reboot brings the configurations back. What might cause this to happen, and how do you fix it?

tech-airman

SubnettingGoddess wrote: »

Wow tech-airman, you are the one with a CCNA and you'd ask such a newb question? I'd think with your l33t skillz, you'd know it does not.

So since the destination IP address in an IP packet only contains the destination IP address, how does the router figure out which network the destination IP address is for?

SubnettingGoddess

tech-airman wrote: »

So since the destination IP address in an IP packet only contains the destination IP address, how does the router figure out which network the destination IP address is for?

No, now it's my turn. Why did all the serial interfaces poof out of the config?

But in answer to your question, it's a routing protocol called PFM.

tech-airman

SubnettingGoddess wrote: »

No, now it's my turn. Why did all the serial interfaces poof out of the config?

But in answer to your question, it's a routing protocol called PFM.

SubnettingGoddess,

What does PFM stand for?

SubnettingGoddess

tech-airman wrote: »

SubnettingGoddess,

What does PFM stand for?

I can't say in polite company. Google it. You still haven't answered my question but I'll give a hint...the answer is buried in a show tech.

rogue2shadow

SubnettingGoddess wrote: »

I can't say in polite company. Google it. You still haven't answered my question but I'll give a hint...the answer is buried in a show tech.

I lol'd.

Took me a second but I got it.

earweed

I got the PFM but what is buried in a show tech?

SubnettingGoddess

earweed wrote: »

I got the PFM but what is buried in a show tech?

incompatible FPGA image version. you could also do a show c7300.

Zartanasaurus

SubnettingGoddess wrote: »

I can't say in polite company.

That shouldn't be a problem with this bunch.