How do I setup and manage a virtualized environment with Kernel based Virtual Machine (KVM) in CentOS or Red Hat Enterpise Linux version 6 server on IBM server? Can you provide step-by-step commands of how to install and manage Virtual Machines (VMs) on a physical server using KVM for RHEL/CentOS version 6.4?

Tutorial details
Difficulty Advanced (rss)
Root privileges Yes
Requirements VT enabled server
Estimated completion time 1h
KVM is part of RHEL and CentOS Linux. You can easily install the same using the following commands. Please note that only the package names have changed in RHEL/CentOS 6.x. If you are using RHEL / CentOS 5.x, read our previous CentOS / Redhat (RHEL) v.5.x KVM Virtulization guide for more information.

When you are tasked with monitoring network traffic on the local network, you can consider many different options to do it, depending on the scale/traffic of the local network, monitoring platforms/interface, types of backend database, etc.

ntopng is an open-source (GPLv3) network traffic analyzer which provides a web interface for real-time network traffic monitoring. It runs on multiple platforms including Linux and MacOS X. ntopng comes with a simple RMON-like agent with built-in web server capability, and uses Redis-backed key-value server to store time series statistics. You can install ntopng network traffic analyzer on any designated monitoring server connected to your network, and use a web browser to access real-time traffic reports available on the server.

As an owner of the website it is very difficult to manage multiple websites without a control panel. However to suit the needs, we need a custom hosting plan.
A Web hosting control panel is a totally web-based interface which has capability to manage your web services under a single location. These web based control panels can manage email accounts, FTP accounts, file management functions, creation of subdomains, disk space monitoring, bandwidth monitoring, create backups and many more.

VnStat PHP a graphical interface application for most famous console mode network logger utility called “vnstat“. This VnStat PHP is a graphical frontend to VnStat, to view and monitor network traffic bandwidth usage report in nicely graphical format. It display IN and OUT network traffic statistics in hourly, days, months or full summary.
This article shows you how to install VnStat and VnStat PHP  in Linux systems.

Ajenti includes dozens of pre-made plugins that let you configure both your OS and server software. List of supported software includes Apache, Cron, CTDB, NFSD, Iptables, Munin, MySQL, Netatalk, NGINX, PostgreSQL, Samba, lm-sensors, Squid 3, Supervisor.
Fast and responsive interface, low memory footprint and handy tools like file manager, terminal and code editor - everything a happy sysadmin needs.

In this recipe, we forward messages from one system to another one. This is used in a number of cases:
the local system does not store any messages (e.g. has not sufficient space to do so)
there is a (e.g. legal) requirement to consolidate all logs on a single system
the server may run some advanced alerting rules, and needs to have a full picture or network activity to work well

Let’s assume you have a physical machine running a Linux system, and you would like to convert this system into a virtual KVM/QEMU machine, keeping everything as close to the original as possible. What follows is my approach.

The first thing we need is a raw image file which mirrors the exact layout of the physical hard drive in our physical server.

In our example scenario, the physical box has one hard drive at /dev/sda with a /boot Partition on /dev/sda2 and a physical LVM volume on /dev/sda3. This LVM volume houses a volume group with two logical volumes, one of them housing the root partition /, and the other one being unused. Also, /dev/sda1 is unused. Grub is installed into the Master Boot Record.

h5ai makes browsing directories on HTTP web servers more pleasant. Directory listings get styled in a modern way and browsing through the directories is enhanced by different views, a breadcrumb and a tree overview.

MySQL Proxy transparently passes information between a client and a MySQL server. The proxy can audit the information flow in both directions and change it if necessary, which could be useful for protecting the MySQL server from malicious queries or for altering the information clients receive without actually making changes to the database. The proxy can also do load balancing between MySQL servers, and perform flow optimization by directing SELECT statements to read-only slave servers, which enhances MySQL scalability by allowing you to add more servers for read operations.

This tutorial shows how to set up a standalone storage server on Ubuntu 12.10. Instead of NFS, I will use GlusterFS here. The client system will be able to access the storage as if it was a local filesystem. GlusterFS is a clustered file-system capable of scaling to several peta-bytes. It aggregates various storage bricks over Infiniband RDMA or TCP/IP interconnect into one large parallel network file system. Storage bricks can be made of any commodity hardware such as x86_64 servers with SATA-II RAID and Infiniband HBA.

ifconfig in short “interface configuration” utility for system/network administration in Unix/Linux operating systems to configure, manage and query network interface parameters via command line interface or in a system configuration scripts.
The “ifconfig” command is used for displaying current network configuration information, setting up an ip address, netmask or broadcast address to an network interface, creating an alias for network interface, setting up hardware address and enable or disable network interfaces.

Czasami transfery w sieci są podejrzanie niskie i zachodzi konieczność wykrycia wąskiego gardła.

Najłatwiej zrobić to przy użyciu narzędzia iperf, dostępnego na wszystkie popularne platformy.

Użytkowanie narzędzia jest bardzo proste

Jeżeli w swojej pracy bądź pasji tworząc nową aplikację trafiliście na konieczność współdziałania php z bazą mssql i do tego na serwerze opartym o debian/ubuntu na pewno trafiliście na problem braku sterownika do połączenia.

Aby móc połączyć naszą aplikację php z serwerem mssql konieczne będzie zainstalowanie i skonfigurowanie freetds.
Można zrobić to w kilku szybkich krokach – oto one:

Every blog or website owner knows the importance of uptime. Downtimes can prove to be totally disastrous for your website’s success. Downtimes occur due to many different reasons such as server problems or high load on server causing high CPU etc. So as a webmaster it is your duty to ensure that the website is up most of the time. Doing this manually is close to impossible, so the wise thing to do would be to use any website monitoring service. A lot of website monitoring services are available out there, but finding the good ones for free is not an easy task. We have a list of Top 10 Awesome Free Website Monitoring Services. They boast all the usual features such as multiple monitoring locations, monitor interval and alert types etc. So check them out and pick the ones that suit your needs the best!

Funambol Open Source Community Forge

The virsh command can be used to mange local or remote guest operating systems. The program can be used to create, pause, and shutdown domains. It can also be used to list current domains.

Daniel Nichter przedstawił na łamach InfoWorldu listę 10 opensource'owych narzędzi dla administratorów baz danych MySQL, które powinny im znacznie ułatwić życie. Przytaczamy poniżej tę interesującą listę – wielu z tych programów wcześniej nie znaliśmy.

Tworzenie zapasowych kopii danych jest bardzo ważne. Są nawet przypadki, w których jest to wręcz obowiązek – na przykład w firmach, czy na serwerach. Niestety prawie żaden użytkownik komputera nie myśli o robieniu kopii zapasowych swoich równie ważnych (dla niego samego) danych, prac, czy chociażby zdjęć z wakacji. A złośliwość rzeczy martwych jest bezwzględna, awaria dysku, a później płacz i lament, ;) z powodu utraty danych. Oczywiste jest to, że nie ma sensu tworzyć kopii zapasowych na tym samym dysku, ale w czasach tanich dysków, również dysków na USB prawie każdy może sobie pozwolić na to. A po za tym kopie możemy tworzyć na zdalnym komputerze/serwerze.

The term network monitoring describes the use of a system that constantly monitors a computer network for slow or failing components and that notifies the network administrator (via email, sms or other alarms) in case of outages. It is a subset of the functions involved in network management.

In today’s cut throat competition, where only the fittest can survive, an organization can’t be called professional, if it lacks network monitoring tools. When almost every company is trying hard to make its online existence more visible and strong, a slight mistake can cost it huge losses. When a visitor comes to a shop or office, he doesn’t mind waiting for few seconds. But in the virtual world, people really don’t have the patience to wait and revisit a down site, unless its their preferred one. A down time of few seconds can cause your loss of reputation as a worthy company.

Thus its highly crucial to invest wisely in network monitoring tools. This list comprises of some free and some paid but all desirable network monitoring tools. You can opt for customized package or an open source tool as per your organization’s requirements, but investment in it is a must. Network monitoring tools gives you both short term benefits and long term yields and you will never regret investing in this.

If you like this article, you might be interested in some of our older articles on Web Analytics Tools, Server Monitoring Tools, Best Twitter Tools, Twitter Tools, and Tools to Make a Web Designer’s Life a Little Easier.