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KVM virt-manager: Install CentOS As Guest Operating System

Now, you have installed the KVM software and required drivers on the host operating systems. You also configured bridged based networking which will provide direct access to the Internet. It is time to create your first guest operating systems. For demonstration purpose you will install CentOS Linux v5.5 using the Internet using virt-manager GUI tool.
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KVM: Install CentOS / RHEL Using Kickstart File (Automated Installation)

Kickstart is a network installation system for RHEL, Fedora and CentOS Linux distributions. Another good option is Cobbler which is a Linux provisioning server that centralizes and simplifies control of services including DHCP, TFTP, and DNS for the purpose of performing network-based operating systems installs. In this tutorial, I’m going to show you how to use kickstart file to install CentOS.
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Linux Tuning The VM (memory) Subsystem

I‘ve fast RAID-10 disk subsystem with multiple SCSI disks. Apps running under modern Linux kernel don’t write directly to the disk. They write it to the file system cache which is managed by Linux kernel virtual memory manager. Since I’ve high performance RAID controller I need to decrease the number of flushes. How do I tune virtual memory subsystem under Linux operating systems for better performance?
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How To Setup OpenVZ under RHEL / CentOS Linux

Ineed to run more than instance of Linux operating system and different Linux distributions under CentOS. How do I use OpenVZ virtualization to optimize the usage of my Dell servers, and create test Linux VPS running Debian, Ubuntu, and CentOS Linux? How do I deploy OpenVZ under CentOS / RHEL Linux?
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Setup FreeBSD Jail With ezjail

How do I setup operating system-level virtualization that allows me to partition my FreeBSD-based server system into several independent mini-systems called jails.? I’d like to set one jail for mail and another for web server via 2 public IP address.
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FreeBSD Jail Allow Ping / tracerouter Commands

I‘m not able to ping from FreeBSD prison (jail). I’m able to resolve the names or use ftp / http for ports but ping and traceroute access is disabled. How do I allow virtualized jail application / users to perform traceroute and ping commands?
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Can I Use Multiple Virtualization Technologies Simultaneously under Linux?

Q. I was reading this article and wanted to try out KVM, XEN, VMWare and VirtualBox simultaneously on my desktop system with 2GB RAM? Why I’m not able to use run multiple virtualization technologies simultaneously under Ubuntu Linux? Can a powerful Linux server run multiple virtualization technologies simultaneously?
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FreeBSD: Nginx Virtual Hosting Configuration

Q. How do I configure Nginx Web server for virtual hosting (host multiple websites under same IP address – name based virtual hosting)?
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FreeBSD Apache Jail: Connection refused: connect to listener on Error and Solution

Q. I’m running Apache 2 server under FreeBSD jail. However, I see lots of warning error messages in /var/log/httpd-error.log as follows:

[Sat Sep 20 20:47:09 2008] [warn] (61)Connection refused: connect to listener on
[Sat Sep 20 20:47:10 2008] [warn] (61)Connection refused: connect to listener on
[Sat Sep 20 20:47:11 2008] [warn] (61)Connection refused: connect to listener on

How do stop all these warning messages flooding my Apache log files?
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How To Upgrade FreeBSD Jail ( OS Level Virtualization )

Q. I’ve FreeBSD jail configured as explained in man pages using make world options. Now I’ve upgrade my base FreeBSD 7.0 system to FreeBSD 7 patch level 4. How do I upgrade my Jail (FreeBSD VPS) so that everything get updated inside jail?
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