Mapping my network

[Samson]

Hi there

I've recently become IT Technician for a school, I've been working their for 5 weeks now, and I'm finding a lot of network related things an uphill struggle.

The reason being, there is no documentation on the layout of the school network, nobody quite knows how many computers are connected, how many wall-points are active, where exactly ALL the switches are, what kind they are etc etc, and asking the county council about this came up with the worst answer they could have possibly given:

"You'll just have to go and survey the network and work it all out."

Now to be perfectly honest, I dont have the time, nor am I authorised to go into roof-space chasing cables.

What I want is some sort of software that can run continually and over a period of weeks, possibly months, map and survey the network from a logical point of view, which computers are used, computer names, etc etc, that way I can get myself some stats to work on.

If I know the logical locations, finding the physical location of all devices will be considerably easier.

I'm quite a proficient VB programmer, I used to do a lot of VB stuff a couple of years back, and if there isnt software already available for doing what I want, I'm prepared to write some.

If anyone knows of any software that can do what I;m asking then that'd be absolutely great, however, if there isnt, then any advice on how I'd go about mapping a network logically without creating too much overhead would be great.

Thanks in advance.

[Altair]

You should check out The Dude: http://www.mikrotik.com/thedude.php

I use this to monitor the state of the school's network.
It will auto scan an entire range of addresses looking for computers or devices.
It shows an icon for each device that is Green for Up, Orange for Mostly Up, and Red for Down. It also shows SNMP, TCP, and other monitoring data.

I imported a map of the school for the background and then placed the computer/device icons in the correct place on the map. Now when a PC goes down I know exactly where to go.

I created my own SVG icons using InkScape so I can tell at a glance what each device is. The process is really easy. You get a bitmap image of the device and let InkScape scan/convert it to vector.

It even exports the current layout to a PDF. Very cool. If you want to see my layout, let me know and I'll see if I can get it small enough to post or send it directly to you.

The Dude made making sense of what had been done by "volunteers" over the last 6 years much easier.

Best thing is that it is easy to get expensed....it is free.

I looked at other tools such as Network Notepad and Kaboodle but found The Dude to be much better for layout and regular use. Though I do miss Kaboodle's right click to launch VNC feature.


[Altair had not been compensated to endorse this product]

Edit: I could not compress the PDF from the school small enough. I have attached zip file containing a PDF from my home PC as well as the PNG exported from the school instead.

[monsterplastic]

I think it would be in your best interest to find out exactly where all your switches/hubs are by looking for them your self.
network mapping software will not tell you which closet your switch is in. If it is faulty and you have to repair it, how do you know where the defective hardware is? In addition some older switches and hubs will not show up with network mapping software. Mapping software generaly uses ICMP packets and SNMP packets to discover devices. Swicthes traditionaly work on layer 2 of the OSI referece model, ICMP and SNMP work at layer 3 so layer 2 devices tend to be invisible to layer 3 ones.

Wiring closests wont tend to be in ceiling voids, they generaly are placed in easy to get too places, engineers want an easy job too! Firsty get a rough Idea how many computers you have and deduce how much network harware you need bearing mind switches tend to come in 24 and 28 port configurations.
If you've got an ICT suite, the cabinet cant be too far away.

Starting a job with a new network is never easy. Only now after being in the school a year can i say i'm confident supporting the various VLANs and understand how all the Cisco kit is programmed.


"You'll just have to go and survey the network and work it all out." sounds like a legitimate and sensible answer to me.

good luck with the new job

[e_g_r]

Dude is ok but as said it dosn't tell you where things are physicaly or what PC is connected to what port.

We are currently mapping our network useing Mode Tap units. Starting at the master cabinet, first patch panel, plug in the master. At the B end (where you think the patch panel leads to in the classroom office) plug in the remote unit. If the lights flash in sequence you have a good link. If they flash out of sequence you have a link with a problem. If you get nothing then your wall outlet marking may be wrong.

By doing this you develop a map of the network, understand its layout and are able to diagnose faults more easily.

It may take a long time but it is well worth the effort.

[Geoff]

I've used Nomad in the past to map networks. It works it out based on snmp information from switches.

http://netmon.ncl.ac.uk/

[plexer]

I presume you know where your servers are connected and have a cabinet there?

I would start from this point and work outwards hopefully there should be some labelling of connections to other cabinets and you can follow this out those and any wall sockets this cabinet feeds.

Once you've mapped everything from the main cab go to one of the others you've identified and repeat the procedure there.

Are there no labels on the faceplates themselves? normally there would be notation on them to describe which cabinet, patch panel and port they connect too.

A cable tester that has a tone tracer facility would help you identify unknown connections as well.

Ben

[molesm]

If you want to see my layout, let me know and I'll see if I can get it small enough to post or send it directly to you.

Yes please Altair

[maniac]

I'va always used 3 com network supervisor, which is a free download from 3com on a 30 day trial, It will build you a virtual map showing how many switches you have, and how they all connect to each other, and if you've got managed switches it will tell you the make, model and IP number of the switch as well.

It's not always 100% accurate with their relative location, but it will tell you what plugs into what, and how many workstations are currently active on the network. Takes a while to complete the scan, but I've always found the maps it produces very helpful.

Hope this helps,

Mike.

[Samson]

Looks like a fantastic little freebie, Ill take a look.

I think out of sheer curiosity and something to do in between un-jamming printers, I might write my own anyway, and just include a few lines in my logon script to grab some data from the computers, OS, memory, etc etc, and save it onto the central shared area, that way I can start building a comprehensive map of my very own!

Cheers

Edit: Yeah the lables on the faceplates and on switching cabinets is hazy at best, the previous technician before me did a lot of wiring and stuff like that himself, and failed to document any of it.

I think a combination of both. Time to get me a tone generator!

Thanks for the replies.

[plexer]

he previous technician before me did a lot of wiring and stuff like that himself

Bet none if it was ever tested or certified then, you have a nice wet string network by the sounds of it.

Ben

[tom_newton]

Anyone got any preferred methods for *recording* this sort of data - its hard to get your head round the entities involved sometimes. For example, when I open a network port for osmeone, its useful to store a name by it, so I know who might scream if I unplug it

[plexer]

You can record ports and things with glpi which when used with ocs ng can inventory all your machines automatically.

Ben

[plexer]

Oh and also when you say open a port for someone care to give me an idea of what you mean as that sounds incredibly geeky

Bit like 24

Ben

[Ric_]

I have a Test-Um Validator ( http://test-um.com/validator/nt950.asp ) which is ace and comes with Plan-Um software for this kind of thing. It is a time consuming and labourious process though unfortunately.

I recommend a tool like the Validator if none of your connections have ever been tested.

[john]

what other -um's do they do I wonder-um hehe wonder if they do a store-um, save-um and pay-um unit