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You may use this software free of charge at your own risk
netdb 3.0.6 (2001-01-29)
Through the remainder of this document we will focus on IP only.
A netdb web GUI has been developed under Linux using the free apache web server, netdb Standard C programs combined with shell scripts and perl scripts.
It has never been the design goal of netdb to be safe even for complete dummies. Some basic tests are performed but please do not rely on netdb to check everything you type in for you and prevent you from making any mistakes. Use netdb while in "brain on" mode, only.
Sorry, but making a GUI "secure" for dummies would increase the implementation effort for it at least by factor 10 and I just won't be able to make that much time any time soon since I do this basically in my spare time on an "Open Source" basis. Also you don't want complete dummies to administer your network, do you?
netdb is not a fully fledged multi user SQL based database system and has only a simple locking mechanism, so please make sure you coordinate your administration efforts.
If more than one person modifies the very same virtual subdomain at the exact same time under very seldom circumstances results may be unpredictable and data loss is possible.
In essence if you have many people administering the same virtual subdomain at a given time there can be a problem.
Different virtual subdomains can be administered at the same time with no problems at all.
Should there ever be any problem with netdb's locking mechanism you may need to remove netdb lock files /tmp/netdb.lck.*
Check out the detailed description of all netdb properties.
Since there's nothing that can stop you from customizing your GUI configuration (files under $NETDB/htm) some of the properties may be removed in data entry forms such as ipxaddr, ipxlan, decnet, x25. If you change any files there please make your own backup of those files since they will be overwritten by future netdb updates.
Being an (Open)Standard and OpenSource supporter I have problems with proprietary standards for good reasons.
Even though X.25 is an international standard it is not "open" since obtaining a copy of that standard is everything but free and it's not on my list of favourite protocols. It's very much outdated, anyway. ;)
What information must be stored inside netdb for each and every interface on the network?
What information should be stored inside netdb for each and every interface on the network?
What information should also be stored inside netdb for each and every interface on the network?
Other properties like x25, decnet, ipxaddr, ipxlan may not even show up in your data entry masks should you have tailored them to your needs, so we currently skip this here.
For each subnet there should be a virtual subdomain. For each subnet different subnet masks can apply. For each subnet a different default gateway (router) will apply which can be internally configured by your netdb admin which is most likely your local hostmaster using netdb.mkdomain. The same applies to potential DNS and WINS servers which are also configured on virtual subdomain level by your netdb admin.
This depends on the operating system you're using. If you want to know which mac you have before you connect it to the network, which is a very good idea, here is a far from complete list of ways how to figure that out:
Operating System command that reveals mac FreeBSD ifconfig | grep ether Linux ifconfig eth0 | grep HWaddr Microsoft Windows 95/98/ME winipcfg Microsoft Windows NT/2000 ipconfig /all
Note that the output format of those commands for mac may differ significantly from what netdb needs. They all are six bytes. Sometimes there are delimiters between bytes such as "-" or ":" sometimes there is no delimiter. If the delimiter is ":" sometimes it can be that leading zeroes are ommited. You must enter mac in netdb format, though, so you may need to convert formats.
There are many other tools also finding out mac. I wrote one of them which I called nbmac. It will run under Microsoft MS-DOS, Microsoft Windows 3.x/95/98/NT and IBM OS/2 provided the networking software used supports NetBIOS. It can be used free of charge at your own risk and downloaded from
If you run more than one nedtb Web GUI browser window you can cut and paste between browser windows and you can search and display results in one browser window to ease editing in another browser window. I highly recommend this.
Below you can see the netdb web GUI main menu:
|Search||open for everyone|
|Input||administer data, access limited|
|Documentation||what's behind netdb?|
Copyright © 1998-2001 by Kostis Netzwerkberatung, netdb 3.0.6 (2001-01-29)
Search is performed using grep, so regular expressions work, too.
Using netdb web GUI everyone can search for entries
Only some web users are allowed to administer data which have to authenticate. Administration in this case means creating, editing, renaming, deleting entries.
csv aka "output sorted by hostname in CSV format" is the netdb network data export function.
When output it displayed on say Microsoft Internet Explorer just go to "Edit, Select All" then "Edit, Copy" and all data is copied into clipboard. Start notepad and paste clipboard content into notepad. Save content into a file with extension ".txt" and then import it into Microsoft Excel or whatever you prefer.
Network data in CSV format can also be (re-)imported but only by your (shell user) netdb admin using netdb.import.
Note that output will include the virtual subdomains so you can use them as search criteria (except for hosts output format).
Your input in the "Search for" field in fact is a so called "regular expression" fed to a program called grep. Those of you familiar with Unix and grep sure have an idea what can be done with that - it's a bit cryptic but very powerful. You can just search a hostname, an ipaddr or mac but you can also make use of regular expressions. For example if you wanted to search for all interfaces in the 192.168.0 network you would enter "192.168.0" and get all hosts in that network as your output. Actually you should type "192\.168\.0\." since "." without a leading "\" means "any character" but there shouldn't be a problem with this in most cases. See a few examples for search patterns below:
What do I search? Search Pattern entry with hostname live live all entries in virtual subdomain .usr \.usr all entries on the Internet \.ext all entries in 192.168.0 network (User LAN) 192\.168\.0\.
Please configure your browser to print in landscape mode for optimal printer output.
Above you can see the netdb Input menu. Access to this menu is only allowed to authorized authenticated users. Access can be limited to selected virtual subdomains or allowed for all virtual subdomains. This is done by your (shell user) netdb admin editing file /etc/netdb/allow and /etc/netdb/htpasswd.
Note: in order to Rename or Delete an entry you must enter an existing hostname before clicking on the respective button.
If you type in a hostname not yet stored in your netdb network database and press [enter] or click on Create/Edit you may be able to create a new entry. However you may only enter data in a virtual subdomain you are explicitely allowed to administer. To make this easier for you only those virtual subdomains you're allowed to administered will be displayed.
If the hostname you typed in is already stored in netdb and you are allowed to edit it, it will automatically let you edit that entry and all properties except for hostname and domain.
Let's see what we can do when we want to create a new entry named example for our User LAN. Let's assume we're allowed to administer all entries which implies an entry in $NETDB/allow containing "*"
First we enter example in the hostname field and then click on Create/Edit. Then we will see a list like this:
Since we want to create example in the .usr virtual subdomain we click on .usr.
We need to enter a correct ipaddr (the number above is the ipnetaddr). ipmask should be supplied correctly as long as the selection above shows information about that. I urgently recommend to supply mac, location also and if at all possible hubport and user. comment can also be of value. Below you can see an example of how a complete entry could look like:
When you click on Save, a few checks will be performed with the virtual subdomain entered:
If any of the checks mentioned above finds a problem your data will not be stored and you'll see an error message that may not look very helpful at first. Sorry about that, but making this more user friendly means a whole lot of work which I currently cannot afford. In any case it's easy to distinguish from a successfully stored entry. In case of a problem, click on the browser Back button, correct the problem and try to Save it again.
Now let's see what we can do if we just want to edit an existing entry. Let's use live as an example.
As we can see hostname and domain fields cannot be edited. That is because moving from one virtual subdomain to another is not implemented on purpose due to the complex checks that need to be performed to do this properly and because there is a rename function for just renaming a hostname within a virtual subdomain. If you need to move a machine from one virtual subdomain to another, delete it first and create it again. I know, that is not very convenient but I can't help it for now.
Now what about about Rename and Delete? Well, this is quite straight forward. Type in the hostname of an existing machine you want to Rename or Delete and click on the appropriate button.
Note that the only field you can edit in Rename mode is the hostname. Also note that you can only rename a hostname that resides in a virtual subdomain you are allowed to administer.
Note that you can't edit any field at all when in Delete mode. Either delete the entry or don't (eg. click on Back). Also note that you can only delete a hostname that resides in a virtual subdomain you are allowed to administer.
Now that you know how to Create, Edit, Rename and Delete entries you may ask yourself how do I know which ipaddr should I enter? How do I figure out what's free? Is there a naming convention for hostnames? To find out which ipaddr is free run another netdb browser window and do a search sorted by ipaddr for the virtual subdomain in question.
If you don't have one, create one. Check out the netdb motivation document about this.