Comments on: DHCP Addresses

By: thevyrys

thevyrys — Fri, 09 Dec 2005 13:54:28 +0000

at a command prompt type nbtstat -a 192.192.192.2

that should return a computer name for you if it is available.
It won’t work for printers and such.

Do the same for each address.

By: tedrizzi

tedrizzi — Fri, 09 Dec 2005 09:33:07 +0000

Your DNS server should have host files for any live computers that are getting an address in that range, and if your using a wins server, it also will have those mappings.

By: ttully

ttully — Fri, 09 Dec 2005 09:12:41 +0000

I know it’s a little too obvious but where is DHCP coming from? If it’s a server, check and see what devices have reservations, as this will contain a list of printers, switches and other devices. As far as computers, you can use “ping -a ipaddress” to get the hostname of the computer with that address.

Not as pretty as the GUI programs available but in a rush it works.

By: atomas

atomas — Fri, 09 Dec 2005 08:46:31 +0000

Angry IP Scanner is great.
Also, in the Windows (if it applies) DHCP server you should have a documented “Reserved” section.
You could have IPs based on MAC addresses and force DHCP.
You should be able to manage all IPs in your network.
I believe these adresses are for servers and printers: have a database for these.

By: dkdoyle

dkdoyle — Thu, 08 Dec 2005 22:27:34 +0000

Well I am going to assume these are hooked to switches. Therefore I would check the arp cache for the address after you ping it. Assuming you can ping it. The mac address will tell you what type of device it is ie: manufacturer and type. Such as HP printer.

By: paul144hart

paul144hart — Thu, 08 Dec 2005 10:48:46 +0000

Another good scanner is GFI LANguard Network Security Scanner.

word of caution – some network devices shutdown ping response for security. be prepared to break the network if you are discovering these devices for the first time.

documenting what you find would be a good idea.

By: thevyrys

thevyrys — Thu, 08 Dec 2005 09:23:04 +0000

you could run Microsoft Baseline Security Analyzer and specify the range of addresses. It should return some information, plus tell where you stand on security, unless they are just devices such as printers, etc.
Ping them as mentioned earlier to see if they respond.

You could also set up some other devices with those addresses and if you get conflicts, wait for the “Help Desk Call”…..that’ll tell you…..

good luck and Merry Christmas!

By: tvgtech

tvgtech — Thu, 08 Dec 2005 00:57:31 +0000

As with all the answers below, you can try superscan as well. This tool will tell you what ports are open as well and tell if you can browse them. Most likely, they are printers, our switches. Use this tool then expand the ports. If http is available, then browse it and see what it is.

You can also use DAMEWARE. This will only tell you if it is a WINDOWS based machine. Then you can shut it dowm shut down services, send the machine a MSG via lan.

Good luck.

By: larrythethird

larrythethird — Wed, 07 Dec 2005 21:14:46 +0000

From any XP machine, you could try nbtstat. It is part of Windows. You could write a batch file to run the whole range. Run “nbtstat -A 192.192.192.10″ to get the name of each computer. If you have a Linux machine, load LinNeighborhood. It can list all of the workgroups, the systems in the workgroup and the available shares.

By: ceescokid

ceescokid — Wed, 07 Dec 2005 18:41:39 +0000

A nice little gui tool I have found to get just such info is the angry IP scanner.
Angry IP scanner is a very fast IP scanner and port scanner. It can scan IP addresses in any range as well as any of their ports. Its binary file size is very small compared to other IP or port scanners.
Angry IP scanner simply pings each IP address to check if it’s alive, then optionally it is resolving its hostname, determines the MAC address, scans ports, etc. The amount of gathered data about each host can be extended with the available plugins.

It also has additional features, like NetBIOS information (computer name, workgroup name, and currently logged in Windows user), favorite IP address ranges, customizable openers, etc.

Scanning results can be saved to CSV, TXT, HTML, XML or IP-Port list file, can be used as a command-line utility in a batch file, etc. With help of plugins, Angry IP Scanner can gather any information about scanned IPs. Anybody who can write code is able to write plugins and extend functionality of Angry IP Scanner.

In order to increase scanning speed, it uses multithreaded approach: a separate thread is created for each scanned IP address.

It is free and open-source software, so use it at your own risk.
Find it here: http://www.angryziber.com/ipscan/