CentOS

CentOS Linux version 6.1 has been released and available for the download. It is a community-supported operating system based on Red Hat Enterprise Linux (RHEL) version 6.1. CentOS Linux is considered as the most popular Linux distribution for web servers and general purposes usage.

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CentOS Linux version 6 has been released. It is a community-supported operating system based on Red Hat Enterprise Linux (RHEL) version 6. CentOS Linux is considered as the most popular Linux distribution for web servers with almost 30% of all Linux servers using it.

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CentOS is a community-supported, freely-available operating system based on Red Hat Enterprise Linux. Lance Davis created CentOS and now he goes absent without leave. In an open letter from his fellow CentOS developers:

You have long promised a statement of CentOS project funds; to this date this has not appeared. You hold sole control of the centos.org domain with no deputy; this is not proper. You have, it seems, sole ‘Founders’ rights in the IRC channels with no deputy ; this is not proper.

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BIND 9 is an implementation of the Domain Name System (DNS) protocols. named daemon is an Internet Domain Name Server for UNIX like operating systems. Dynamic update messages may be used to update records in a master zone on a nameserver. When named receives a specially crafted dynamic update message an internal assertion check is triggered which causes named to exit. An attacker which can send DNS requests to a nameserver can cause it to exit, thus creating a Denial of Service situation. configuring named to ignore dynamic updates is NOT sufficient to protect it from this vulnerability. This exploit is public. Please upgrade immediately.

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Don't tell anyone that I'm free

OpenSSH is the implementation of the SSH protocol. OpenSSH is recommended for remote login, making backups, remote file transfer via scp or sftp, and much more. SSH is perfect to keep confidentiality and integrity for data exchanged between two networks and systems. However, the main advantage is server authentication, through the use of public key cryptography. From time to time there are rumors about OpenSSH zero day exploit. Here are a few things you need to tweak in order to improve OpenSSH server security.

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As a system admin, I need to use additional hard drives for to provide more storage space or to separate system data from user data. This procedure, adding physical block devices to virtualized guests, describes how to add a hard drive on the host to a virtualized guest using VMWare software running Linux as guest.

It is possible to add or remove a SCSI device explicitly, or to re-scan an entire SCSI bus without rebooting a running Linux VM guest. This how to is tested under Vmware Server and Vmware Workstation v6.0 (but should work with older version too). All instructions are tested on RHEL, Fedora, CentOS and Ubuntu Linux guest / hosts operating systems.

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Need to monitor Linux server performance? Try these built-in commands and a few add-on tools. Most Linux distributions are equipped with tons of monitoring. These tools provide metrics which can be used to get information about system activities. You can use these tools to find the possible causes of a performance problem. The commands discussed below are some of the most basic commands when it comes to system analysis and debugging server issues such as:

  1. Finding out bottlenecks.
  2. Disk (storage) bottlenecks.
  3. CPU and memory bottlenecks.
  4. Network bottlenecks.

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