Any strategy to learn a network

[confuseis]

Hi all

I’m wondering does anyone have a particular routine or strategy for understanding a new network that is undocumented and you have no support. How do you get yourself up to speed in the absence of supervisor or training in finding out how the traffic flows around the network and figure out how the and interpret the data, demystify that mass of unlabelled machines and gazillion cables in the server rack etc.

e.g. what commands can I run, what applications can help, what to look for physically. This looks like it will take forever, I have some basic networking knowledge but Ive a tendancy to freeze and be overwhelmed in this situation, people expect you to know the network inside out after your first week.

Thanks for reading

 

[Hawkeye22]

I don't know where you just got a job at, but I feel sorry for you. I use a label gun and always label both ends of an ethernet run so I can find it easily later on. I also document that label in a log/journal and write down which room I can fine the cable ends in.

Every computer/device that has a static IP gets written to the journal along with the computer's/device's location and workgroup/domain name and computer name. For computers that get an address assigned via DHCP I just list the above info minus the IP address.

I also log all servers, their locations, and functions.

This not only makes it easy on myself months or years later, but if I ever have to train somebody or just decide to quit my job, the next person won't have such a tough time.

I at least hope they are paying you well. I know this isn't an answer, but you may want to take this into consideration for the person that will eventually replace you.

 

[riser]

Log into a system from the console and label them.

As far as the networking side, you can use the command line "Tracert" to see how traffic flows from one system to the next. By following that data you can start labeling that equipment. Once you get started it should provide a fairly clear picture of the layout.

You can grab third party tools that do a lot of graphing and mapping for you but it sounds like you're going to be learning this on the cheap.

 

[landran]

What kind of OS is being run on this network? Windows (probably)/*nix (hopefully)/Apple (quit now)/some other flavor? Anything details you could provide would make helping you alot easier.

As far as some FREE "third party tools" a google search turned up some (possible) help:

1. For Microsoft: http://www.10-strike.com/lanstate/
-free 30 day trial

2. For Microsoft: http://www.solarwinds.com/products/lansurveyor/
- free trial

3. Multi-Platform: http://nmap.org/zenmap
-Free and graphical

I think these would be a good place to get an idea of the network topography. As far as tracking the physical hardware down, I can't help you there. You're the one that's onsite.

Just some background, I don't work in the network field and I'm probably entirely wrong on this. I do NOT claim to have any idea what I'm doing and, to be honest, I have no idea where I am. I'm just trying to help a fellow human being out.

 

[1sAND0s]

ah yes... and they'll tell you it's a great exercise for you to learn the network

i've been there and these helped me:

1. if you're using cisco, enable CDP on your internal links
2. find your dhcp servers and see what's happening there
3. some tools will actually map a network for you (i think cacti has that ability)
4. each time you learn what a link connects to, label it accordingly (both physically and on the switch/router interface)

it's a time-consuming task, so go slow and steady.

best of luck!

 

[Catsrules]

http://www.spiceworks.com/
Is a good free management software
Does a network scan, to look for devices, Might help you out for finding what does what.
If you know admin passwords for stuff, spiceworks can log in and get information from them.

 

[confuseis]

Late reply I know as ive been v busy, followed your advice guys and life is gettin much easier

just wanted to say

Many thanks