In Linux:

The linux fuser command has a special option for port conflicts.

Use fuser -n tcp <port id> for tcp ports to see which process is using the port.

For example to see which application is already using port 80 use:

$ fuser -n tcp 80

The netstat command can also be used to determine what process is using a port.

Use netstat -nlp and you should see PID and names of programs along with the port they are using (note you can only see the PID of process you own, unless running as root)

$ netstat --nlp

In Windows:

On Windows 2003 the options are as follows: netstat -a -b -o -n

• -a: gets listening processes (similar to -l on linux)
• -b: displays the executable name that started using the port (similar to -p on linux)
• -o: displays the process id (PID) that owns the connection
• -n: (optional) gives the addresses numerically (same as -n on linux)

Posted by Alex | No Comments »

The DNS is a distributed, hierarchical database where authority flows from the top (or root) of the hierarchy downward.

When thinking of the structure of the DNS, imagine an inverted tree. Each branch of the tree is within a zone of authority; however, multiple branches of the tree can be within a single zone.

The software (Bind being the most common) that stores domain name information is called a domain name server. A single name server can be authoritative for multiple zones. All zones have a primary master and a secondary master name server that provides authoritative responses for their zones.

If you query a name server not authoritative for a particular zone, that name server will most likely have up-to-date information. This is because zone information propagates throughout the Internet at regular intervals, and name servers cache zone information for which they are not authoritative.

DNS Commands

(more…)

Posted by Alex | No Comments »

Anybody who decides to get a web hosting service or facility for their website will also soon be faced with the tough question of what server they will need. Will their website be run by a Windows server operating system or will they prefer to go for a Unix system?

Typical Windows servers will run on Windows NT, Windows 2000 or Windows XP, while Unix servers could be Linux or Open BSD to name just two. The truth is that both systems have there pros and cons.

(more…)

Posted by Alex | No Comments »

The first step would be to check if your system has Windows XP drivers. If they are not available, you can still try to downgrade the operating system, but be prepared for some missing features or hardware support.After downloading the Windows XP drivers, simply get a licensed copy of the operating system and perform a fresh install on your PC. Then load up the drivers and you are good to go. Though it is technically possible to downgrade from Vista without performing a fresh install, and thereby saving your data files, we do not recommend it as some residue registry entries may result in system conflicts down the road.

As with all software installations, please ensure that you have backup your important data and read the necessary instructions before proceeding.

Posted by Alex | No Comments »