iftop: Installation guide

If you have a server and you wish to get the actual bandwidth usage on real time basis, you may simply install iftop from your server to track the information time by time.

iftop is a good network monitoring tool to check real time network bandwidth usage and CPU usage.

To download iftop,

# cd /usr/src
# wget http://www.ex-parrot.com/~pdw/iftop/download/iftop-0.17.tar.gz

To install iftop,

# cd /usr/src
# tar zxf iftop-0.17.tar.gz
# cd iftop-0.17

# ./configure
# make
# make install

To use iftop, you may simply type in iftop,


Or specify the network interface,

iftop -i eth0

Change your Network IP with CentOS

For some purpose, you might want to change the Network IP from your CentOS server such as switching the data center, etc.

To done this, just simply check your main network interface with typing ifconfig from the server.Then get the network interface name.

Next, edit the file from

You shall see the following setting.
# Intel Corporation 80003ES2LAN Gigabit Ethernet Controller (Copper)

Change the IPADDR to the new server IP.

Note: You might need to change the Broadcast, Netmask, Network or Gateway with the need.

Useful Linux Monitoring Tools

If you still remember Mick Genie ever post on how to monitor RAM/Memory on Linux earlier from http://www.mickgenie.com/monitor-rammemory-on-linux/, you should have an idea on the basic command to monitor Linux server.

Today I would like to share some useful monitoring tools from Linux box. With Linux monitoring tools, it uses to analysis and debugging the Linux box.

1. Top Process
– Top process is the most used by the Linux user as it come with many useful information such as it’s server load, memory, iostat, etc.

With top command, it do comes with some hotkey.
t – Displays summary information off and on.
m –    Displays memory information off and on.
A –    Sorts the display by top consumers of various system resources. Useful for quick identification of performance-hungry tasks on a system.
f –    Enters an interactive configuration screen for top. Helpful for setting up top for a specific task.
o –    Enables you to interactively select the ordering within top.
r –    Issues renice command.
k –    Issues kill command.
z –    Turn on or off color/mono Continue reading Useful Linux Monitoring Tools

Basic Network Commands in Windows

Today, I will show some Network commands used in Windows Operating System. You might use some of the command daily and some of it which is useful but you have never used it.

This is a tools that always use to check the DNS information such as ns, a, mx, txt, etc. Sometimes, it is important to check the DNS if your domain entered to the expired and you have forgotten to renew your domain name causing the domain provider temporarily change your DNS information.

tracert is trace route in Linux and it is the same like trace route, with tracert, you are allowed to understand the hop route from your PC to the server (destination).

arp -a
With the command “arp -a”, it gives you the IPs list of your internal network and easily to allow you to know which IPs used in your network if you are not using DHCP network.

ping is the mostly used to understand if a domain or IP able to return the response in short time.

ipconfig is widely used by network administrator to test out some of the testing on the internal network and the command could be /all, /flushdns, etc.

pathping is the advance(newer version) of tracert and it show you the result in another method.

How to manually open ports in Internet Connection Firewall in Windows XP

To manually open a port, follow these steps:

  • Click Start, and then click My Network Places.
  • Under Network Tasks, click View Network Connections. (Or, right-click My Network Places on the desktop, and then click Properties.)
  • Right-click the connection that you use for the Internet, and then click Properties.
  • Click the Advanced tab, and then click Settings.
    Note If the Settings button is unavailable, ICF is not enabled on this connection, and you do not have to open any ports (because they are all already open).
    Continue reading How to manually open ports in Internet Connection Firewall in Windows XP