A Software That Controls The Brightness Of Your Linux Computer Screen
Well, if you are a Linux user, your screen worries can be put to rest with a free to download software, f.lux.
Wednesday, April 10, 2013: When you are working day in and day out on your laptop, your eyes will end up taking the brunt. Especially, when the time of the day changes, your eyes automatically stress more to work on the device, it is because the brightness differs. Well, if you are a Linux user, your screen worries can be put to rest with a free to download software, f.lux.
“f.lux makes your computer screen look like the room you're in, all the time. When the sun sets, it makes your computer look like your indoor lights. In the morning, it makes things look like sunlight again. Tell f.lux what kind of lighting you have, and where you live. Then forget about it. f.lux will do the rest, automatically,” reports the official page.
These Books Will Help You Learn More About Linux
You have the basic reference guidebook to understand system administration and lot more.
Saturday, April 06, 2013: Linux as an operating system is faced with mixed responses across the globe. Some Linux enthusiasts adore the platform to such an extent that, hating Windows for them is a necessity.
But in terms of understanding the dynamics of Linux, one cannot rely on the epitome of research, i.e. Google. Even in this digital age, where everything is available on the Internet, to learn the deeper knowledge and understanding about Linux, the best way is to adopt the traditional method of reading books.
The following list comprises five books that could enable you to master the trade of working on the Linux platform and other complex and high-tech functions as well.
Linux Pocket Guide As the name suggests, Linux Pocket guide is basically seen in the form of a comprehensive reference book, which offers a lot of material on Linux. This guide is a must for Linux administrators and for students, studying Linux-based certifications.
Unix and Linux System Administration Handbook
This book, currently in its fourth edition covers all the information related to Linux and UNIX system administration. The book is divided into three parts, basic administration, networking and other additional content. Basic administration offers a broad overview of UNIX and Linux from a system administrator's point of view, that will enable you to administer your own system.
Networking involves rules used on UNIX and Linux that help set up, extend and maintain networks and Internet-facing servers. The last part comprises of other information like virtualization, Eco-friendly computing and more.
Linux in a Nutshell
This book helps you to understand the operating system in a deeper sense. It is a book that apparently covers almost everything about Linux. The book has been written by four established authors from the Linux community, and includes varied topics that both beginners and experts will find useful.
The Linux Programming Interface: A Linux and UNIX System Programming Handbook
This book also talks about the Linux and UNIX programming interfaces. Written by Micheal Kerrisk, it offers an in-depth insight into all the system calls and library functions that are required to gain expertise in system programming. The book is loaded with examples, exercises, diagrams and detailed descriptions that offer assistance in every possible way.
A Practical Guide to Linux Commands, Editors, and Shell Programming
The book pen-down by Mark. G. Sobbell, explains the basic strategy to work with the Linux operating system from the command line. Apart from that, it also comes with coverage of Mac OS's command line interface also.
12 Command Line Tools to Monitor Linux Performance
It’s really very tough job for every System or Network administrator to monitor and debugLinux System Performance problems every day. After being a Linux Administrator for 5 years in IT industry, I came to know that how hard is to monitor and keep systems up and running. For this reason, we’ve compiled the list of Top 12 frequently used command linemonitoring tools that might be useful for every Linux/Unix System Administrator. These commands are available under all flavors of Linux and can be useful to monitor and find the actual causes of performance problem. This list of commands shown here are very enough for you to pick the one that is suitable for your monitoring scenario.
12 Linux Monitoring Tools
1. Top – Linux Process Monitoring
Linux Top command is a performance monitoring program which is used frequently by many system administrators to monitor Linux performance and it is available under many Linux/Unixlike operating systems. The top command used to dipslay all the running and active real-time processes in ordered list and updates it regularly. It display CPU usage, Memory usage, Swap Memory, Cache Size, Buffer Size, Process PID, User, Commands and much more. It also shows high memory and cpu utilization of a running processess. The top command is much userful for system administrator to monitor and take correct action when required. Let’s see top command in action.
Top Command Example
2. VmStat – Virtual Memory Statistics
Linux VmStat command used to display statistics of virtual memory, kernerl threads, disks,system processes, I/O blocks, interrupts, CPU activity and much more. By default vmstat command is not available under Linux systems you need to install a package called sysstat that includes a vmstat program. The common usage of command format is.
procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu-----
r b swpd free inact active si so bi bo in cs us sy id wa st
1 0 0 810420 97380 70628 0 0 115 4 89 79 1 6 90 3 0
3. Lsof – List Open Files
Lsof command used in many Linux/Unix like system that is used to display list of all the open files and the processes. The open files included are disk files, network sockets, pipes,devices and processes. One of the main reason for using this command is when a disk cannot be unmounted and displays the error that files are being used or opened. With this commmand you can easily identify which files are in use. The most common format for this command is.
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
init 1 root cwd DIR 104,2 4096 2 /
init 1 root rtd DIR 104,2 4096 2 /
init 1 root txt REG 104,2 38652 17710339 /sbin/init
init 1 root mem REG 104,2 129900 196453 /lib/ld-2.5.so
init 1 root mem REG 104,2 1693812 196454 /lib/libc-2.5.so
init 1 root mem REG 104,2 20668 196479 /lib/libdl-2.5.so
init 1 root mem REG 104,2 245376 196419 /lib/libsepol.so.1
init 1 root mem REG 104,2 93508 196431 /lib/libselinux.so.1
init 1 root 10u FIFO 0,17 953 /dev/initctl
4. Tcpdump – Network Packet Analyzer
Tcpdump one of the most widely used command-line network packet analyzer or packets sniffer program that is used capture or filter TCP/IP packets that received or transferred on a specific interface over a network. It also provides a option to save captured packages in a file for later analysis. tcpdump is almost available in all major Linux distributions.
# tcpdump -i eth0
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
22:08:59.617628 IP tecmint.com.ssh > 188.8.131.52.static-mumbai.vsnl.net.in.28472: P 2532133365:2532133481(116) ack 3561562349 win 9648
22:09:07.653466 IP tecmint.com.ssh > 184.108.40.206.static-mumbai.vsnl.net.in.28472: P 116:232(116) ack 1 win 9648
22:08:59.617916 IP 220.127.116.11.static-mumbai.vsnl.net.in.28472 > tecmint.com.ssh: . ack 116 win 64347
5. Netstat – Network Statistics
Netstat is a command line tool for monitoring incoming and outgoing network packets statistics as well as interface statistics. It is very useful tool for every system administrator to monitor network performance and troubleshoot network related problems.
Htop is a much advanced interactive and real time Linux process monitoring tool. This is much similar to Linux top command but it has some rich features like user friendly interface to manage process, shortcut keys, vertical and horizontal view of the processes and much more. Htop is a third party tool and doesn’t included in Linux systems, you need to install it using YUM package manager tool. For more information on installation read our article below.
7. Iotop – Monitor Linux Disk I/O
Iotop is also much similar to top command and Htop program, but it has accounting function to monitor and display real time Disk I/O and processes. This tool is much useful for finding the exact process and high used disk read/writes of the processes.
Iotop Command Example Screenshot
8. Iostat – Input/Output Statistics
IoStat is simple tool that will collect and show system input and output storage device statistics. This tool is often used to trace storage device performance issues including devices, local disks, remote disks such as NFS.
IPTraf is an open source console-based real time network (IP LAN) monitoring utility forLinux. It collects a variety of information such as IP traffic monitor that passes over the network, including TCP flag information, ICMP details, TCP/UDP traffic breakdowns, TCP connection packet and byne counts. It also gathers information of general and detaled interface statistics of TCP, UDP, IP, ICMP, non-IP, IP checksum errors, interface activity etc.
IP Traffic Monitor
10. Psacct or Acct – Monitor User Activity
psacct or acct tools are very useful for monitoring each users activity on the system. Both daemons runs in the background and keeps a close watch on the overall activity of each user on the system and also what resources are being consumed by them.
These tools are very useful for system administrators to track each users activity like what they are doing, what commands they issued, how much resources are used by them, how long they are active on the system etc.
11. Monit – Linux Process and Services Monitoring
Monit is a free open source and web based process supervision utility that automatically monitors and managers system processes, programs, files, directories, permissions, checksums and filesystems.
It monitors services like Apache, MySQL, Mail, FTP, ProFTP, Nginx, SSH and so on. The system status can be viewed from the command line or using it own web interface.
Monit Linux Process Monitoring
12. NetHogs – Monitor Per Process Network Bandwidth
NetHogs is an open source nice small program (similar to Linux top command) that keeps a tab on each process network activity on your system. It also keeps a track of real time network traffic bandwidth used by each program or application.
NetHogs Linux Bandwidth Monitoring
We would like to know what kind of monitoring programs you use to monitor performance of your Linux servers? If we’ve missed any important tool that you would like us to include in this list, please inform us via comments and please don’t forget to share it.