Venting about VLSM

Node Man

Hi Everybody,
This is my first time venting on the forum so i am including this in off topic:

Is it me, or are VLSM questions just a cruel joke in order to make us calculate 5 subnet ranges?!?!

Thanks for listening.

NotHackingYou

They are much easier with practice!

SteveO86

Just wait till you interview for engineering positions and they hand you questions expecting you subnet various class C and maybe a Class B subnet on paper

veritas_libertas

If you are referring to the practice questions from Odom's ICND2 book by Boson, than yes, they are cruel...

jamesleecoleman

It's kinda fun when you get the hang of it.

CodeBlox

SteveO86 wrote: »

Just wait till you interview for engineering positions and they hand you questions expecting you subnet various class C and maybe a Class B subnet on paper

Do interviewers really ask that type of thing for an engineer position? I would love that question! Subnetting is so easy and I can do it pretty quickly WITHOUT paper in my head.

boredgamelad

One of the questions on our screening exam for security engineers (all levels, I-III) asks how many usable IP addresses are in a /23 network. You would be shocked at how many people get that one wrong, especially considering A.) it's pretty easy and B.) it's an online exam so you could easily Google the answer.

Xyro

CodeBlox wrote: »

Do interviewers really ask that type of thing for an engineer position? I would love that question! Subnetting is so easy and I can do it pretty quickly WITHOUT paper in my head.

I wish I could get paper in my head

sratakhin

CodeBlox, +1.

I'd rather do a VLSM question than answer some obscure questions about a protocol I never used.

DevilWAH

jamesleecoleman wrote: »

It's kinda fun when you get the hang of it.

OK you are just strange!

I have to say I came in to networking from a VLSM angle, so to me VLSM seems natural, to think people use to use classful networks seems strange.

CodeBlox

Ha, +1 for that! I agree!! What is with those strange people using a whole class A address space?

veritas_libertas

It's not the subnetting that bothers me, it's the way they ask the questions in the Boson practice tests. I actually enjoy subnetting.

Blackout

Its exactly like subnetting once it clicks, its easy. I think Jeremy's way is pretty easy.

DevilWAH

I have a really simple way to deal with sub netting.

first thing i do when I walk in to an exam is write out a sheet for all /16 and longer subnets, with CDR, mask, wildcard, hosts, step, host bits, network bits, binary notation.....

Only takes a few minutes and saved having to think and detracts myself when answering questions. I have one the same thing on the wall at work, the last thing I want to to make a silly mistake in the middle of another question or when configuring a network.

I should note I don't write it out from memory, i still work it out, and I would suggest this is a great way to learn it. If you can sit down with a blank bit of paper and write out all the major bits of information from a /16 to a /32 network you are well on your way to understanding how it fits together. In fact any one struggling with VLSM I would suggest gives it a try.

Blackout

LOL! I do the same thing but I write 1 through 255, and my block sizes. Takes time but I have 15 minutes during the tutorial. I usually write down stuff like public IP range, Private IP range. The proctor looked at me crazy when I turned everything in cause both sides of my laminated sheet completely filled.

networker050184

CodeBlox wrote: »

Do interviewers really ask that type of thing for an engineer position? I would love that question! Subnetting is so easy and I can do it pretty quickly WITHOUT paper in my head.

I've never been asked a subnetting question in an interview.

DevilWAH

CodeBlox wrote: »

Do interviewers really ask that type of thing for an engineer position? I would love that question! Subnetting is so easy and I can do it pretty quickly WITHOUT paper in my head.

yes they can for entry level network posts. Thank god them times are behind me!

I hate doing it in my head, which is why I would take paper and pen in, its not just for notes In one of my first interviews they looked on in amusement as I did it long hand in binary. Still got the job though..

So don't worry if you are not quick, just make sure you know how to get it right, people will overlook you taking a few extra minutes to make sure you get it right. However they don't like it when you take down the network because you rushed and get it wrong.