Tips

Tips

Linux servers

• How to configure Postfix MTA on Red Hat Enterprise Linux 6

  Red Hat Enterprise Linux 6 uses Postfix for mail transmission. Learn how to configure the open source mail server in your Linux system.  Continue Reading

• Signing Linux RPM files using a Gnu Privacy Guard key

  Signing Linux RPM packages assures users of the package that the RPM has not been tampered with. Learn how to create a Gnu Privacy Guard key and sign your RPM packages.  Continue Reading

• Creating RPM packages in Linux

  RPM software management on Linux systems truly has an advantage when you create your own RPM packages. Learn how to use the enhanced vim option to automatically generate a template file after creating a new RPM file with the .spec extension.  Continue Reading

• Using Zabbix for open source network management

  Proactive monitoring and other advanced features have contributed to the growing popularity of Zabbix as an open source network-management tool.  Continue Reading

• Optimizing Linux for SSD usage

  Default Linux settings won't allow you to take advantage of SSD performance gains. Learn four ways to optimize SSD performance on your Linux system in this tip.  Continue Reading

• Using Vagrant with Puppet to create VirtualBox hosts

  Vagrant integrates with Puppet and Chef to automate configuration management to build VirtualBox hosts. Linux systems admins can use this technology for quickly creating development hosts and production hosts.  Continue Reading

• Setting up a centralized Linux log server

  One of the many benefits of using Linux as a central logging server is that you can set up logging via syslog. Syslog allows messages to be sent over the network to a centralized log host, which is the ideal scenario for managing logging.  Continue Reading

• Exploring the features of the XFS file system on Linux

  The XFS file system has been designed to deal with high file volumes and large files more efficiently. Find out how the file system manages these files, and when it might be appropriate to use this file system on your Linux servers instead of Ext3 ...  Continue Reading

• Deciding when to use Linux file system barriers

  Linux file system barriers in Ext3 and Ext4 protect data written to the journal. Learn how these barriers work and in which use cases they are a benefit, and in which cases you should disable them on your Linux servers.  Continue Reading

• Doing business with Apache OFBiz: Open source ERP solution

  Many large sucessful enterprises use Apache OFBiz as their ERP solution. Find out how to get started with this open source tool for your e-business.  Continue Reading

• Configuring load balancing with Linux Virtual Server

  Using Linux Virtual Server, learn how to configure load balancing to help avoid busy servers and achieve optimal resource utilization on your Linux system.  Continue Reading

• Working with Linux file system attributes

  File system attributes can provide a valuable addition to the way you ensure security on your Linux server. Learn how to mount, list and change file system attributes in ext4.  Continue Reading

• Building massively distributed applications with Hadoop

  Hadoop has become the de facto solution for distributed data processing. Learn about how this open source project from the Apache Software Foundation creates reliable, scalable, distributed computing, and its four subprojects: Hadoop Common, HDFS, ...  Continue Reading

• SELinux tutorial: Introduction to Linux kernel security

  SELinux may seem too complex for some administrators who instead disable the useful Linux kernel security tool. Learn how SELinux works, including how subjects and objects work and security policy settings.  Continue Reading

• Setting up MindTouch document management on a Linux system

  MindTouch is an open source document management system alternative to SharePoint and other commercial software. In this tip, learn how to set up MindTouch on a Linux server, using CentOS 5.5 as the example system.  Continue Reading

• RHEL 6 ditches System V init for Upstart: What Linux admins need to know

  System V init is fading to a memory in Linux boot systems as the new Linux disdribution releases, such as Red Hat Enterprise Linux 6, switch to using Upstart. Learn what is different with this boot service and how to work with it to get your Linux ...  Continue Reading

• Optimizing SUSE Linux performance for VMware environments

  Learn how to optimize Suse Linux Enterprise Server (SLES) on VMware by optimizing VMware and SUSE. For better performance, switch to VMware's paravirtualization disk driver and adjust I/O settings in SUSE along with changing the journal settings.  Continue Reading

• Bash commands for navigation, sharing, and find

  Learn how to use Bash on a Linux server to change command line navigation, switch around in directories, file first redirection, three find commands, and how to show people the command line without giving them access through rerouting.  Continue Reading

• Red Hat Enterprise Linux security mechanisms: SELinux, iptables and more

  When setting up Red Hat Enterprise Linux on your data center servers, you need to make security decisions. Learn about security options for RHEL including SELinux, iptables firewall, TCP Wrapper and application security use considerations.  Continue Reading

• Creating an inventory with nmap network scanning

  Nmap network scanning generates a full system inventory, but it's only usable with the right parameters and output format. Learn how to create an nmap inventory in this tip.  Continue Reading

• Mounting file system resources with AutoFS

  AutoFS allows resources to be mounted on an as-needed basis, simplifying the management of NFS shares. This tip walks you through the process of setting up AutoFS.  Continue Reading

• Setting up a syslog server in Linux

  A central logging server can make it easier to manage logs. In this tip, learn how to collect and centralize syslog messages from your hosts onto one syslog server in Linux.  Continue Reading

• Zenity tutorial: How to automate Linux admin scripting

  In this Zenity tutorial for Linux admins, learn how to set up Zenity and use its dialogs to automate scripting.  Continue Reading

• Using your Linux server to create an ad-hoc wireless network

  In this tutorial, an expert explains how to set up an ad-hoc wireless network access point with your Linux server.  Continue Reading

• Common Linux security policy management gaps

  Linux security is commonly overlooked in IT security policies, especially when management is out of touch with what’s happening on the ground.  Continue Reading

• Sharing Windows files with the Linux CIFS client

  It can be surprisingly easy to share files between Linux and Windows with the Linux CIFS client. In this tip, learn how to install the Samba client and set up CIFS on Linux.  Continue Reading

• Kerberos authentication in RHEL: Easing Windows-Linux integration

  Kerberos authentication for CIFS offers easier Windows-Linux integration. In this tip, learn how Kerberos authentication works and how to set it up in Red Hat Enterprise Linux.  Continue Reading

• Unix overview: The latest features in AIX, HP-UX and Solaris

  Each of the major Unix versions have been updated with useful new features recently. In this overview, get up to date on the features you should know about in the latest releases of IBM AIX, Hewlett-Packard's HP-UX and Oracle's Solaris.  Continue Reading

• Displaying Puppet reports on Puppet Dashboard

  Managing configurations with Puppet just got easier. In this tip, learn how to display your Puppet reports on the Puppet Dashboard GUI.  Continue Reading

• Optimizing Linux swap space usage

  Today's powerful servers with plenty of RAM can make swap space seem like a thing of the past, but knowing how much you need can help keep your system running smoothly.  Continue Reading

• Installing the ModSecurity Web application firewall on Red Hat Enterprise Linux

  Learn how to set up the ModSecurity Web application firewall on Red Hat Enterprise Linux 5.4 and Apache Web server 2.2.x. This firewall monitors access to Web servers to ensure that requests are valid and not malicious.  Continue Reading

• The history of Unix on the PC: Exploring lesser-known variants

  This tip explores the history of Unix, from its creation by AT&T in the 1960s to its present-day use on x86 hardware and PC-compatible systems. Brush up on your Unix history and learn about Unix variants that you never knew existed.  Continue Reading

• Determining the true value of a server operating system

  One of the most critical decisions a network manager can make is which server operating system to deploy. Making that choice is fraught with budget limitations, corporate politics and a numerous other factors. Here, an expert discusses how to ...  Continue Reading

• Securely connecting Linux servers to WiFi using the command line

  Connecting a Linux server to WiFi requires the use of the command line. Learn the commands and procedures for wireless networking in your Linux data center.  Continue Reading

• Overcoming common Unix-to-Linux migration pitfalls

  You may encounter problems when moving from Unix to Linux. Learn about hardware and application compatibility challenges and how to overcome deployment errors and how to prevent them including client testing, shell script testing, and more.  Continue Reading

• Linux distribution migration: Planning for efficiency

  Migrating from one Linux distribution to another to consolidate the operating systems within your data center? Learn what steps are needed for a smooth transition with support.  Continue Reading

• Weighing Linux server consolidation tools

  Choosing the best Linux server consolidation software for your data center hinges on factors other than cost. This tip compares Novell's PlateSpin, HP and VMware's Capacity Planner in terms of your data center requirements.  Continue Reading

• Booting a Xen virtual machine from CD-ROM or DVD

  If your Xen virtual machine fails, you may want to boot it from an installation disk and run the rescue program. Learn the required steps to succesfully boot a Xen virtual machine from a disk on a Linux machine.  Continue Reading

• Five things you didn't know Bash could do on Linux

  Bash offers a lot of tools to Linux admins, and it may take you years to get a handle on all the useful ones. Learn five lesser-known Bash scripts for your Linux systems including extended globbing, cdspell shell options, improved Bash history, ...  Continue Reading

• Using libguestfs to easily access Linux virtual machine file systems

  Libguestfs is a library on Linux that helps you access and modify virtual machine disk images. You can then run Linux commands and troubleshoot the machine image from the libguestfs shell or host operating system. Learn how to navigate libguestfs, ...  Continue Reading

• Common security flaws to check for on your Linux-based Web systems

  Your Linux server may have Web application-related security vulnerabilities that should be checked out and repaired. These can include passwords, PHP code injection, weak file and directory permissions and outdated Apache and PHP versions. Learn ...  Continue Reading

• Making Sybase database upgrading easier with 'A Practitioner's Guide to upgrading to Sybase ASE 15'

  Learn more about the nuances of the upgrade to Sybase ASE 15 in this Q&A with a veteran Sybase expert and author of 'A Practitioner's Guide to upgrading to Sybase ASE 15.'  Continue Reading

• Novell drops NetWare support: What do millions of users do?

  Novell's NetWare support is ending and millions of users must choose a new OS with comparable services. This tip outlines possible strategies for replacing NetWare.  Continue Reading

• Fixing Linux I/O write performance problems

  Learn how to optimize your Linux server for I/O writes by adjusting I/O scheduler settings and journaling settings along with some advice about partition set-up.  Continue Reading

• Using common Linux mail clients with an Exchange Server

  Begin your migration away from Microsoft Exchange by learning how to set up Linux mail clients, Evolution and Thunderbird, to talk to Exchange.  Continue Reading

• Analyzing Linux write performance problems with iotop

  Write performance on a Linux system may be causing a performance problem, and iotop shows you how the write processes are affecting I/O and storage. The iotop Linux command is more informative than top for determining the cause of the Linux server ...  Continue Reading

• Patching running Linux kernels on servers with no reboot using Ksplice Uptrack

  Ksplice Uptrack keeps Linux servers up-to-date with recent kernel security patches without rebooting, saving time and reducing down-time for mission critical production servers. Learn how the tool works and hear about a Linux-based hosting provider ...  Continue Reading

• Creating a simple backup solution for Linux with rsynch, SSH, and cron

  To create simple backups for Linux workstations, you can use rsynch with an SSH connection to a server and automate cron. Learn how to set-up your Linux system to automate your backups using tools available with every Linux distribution.  Continue Reading

• Installing Ubuntu 9.10 and the Eucalyptus enterprise cloud computing platform

  Learn how to install Ubuntu 9.10 server edition with Eucalyptus enterprise cloud and set it up to manage applications on AWS or other infrastructure services. Features of the Ubuntu store, including available operating system images and the use of ...  Continue Reading

• Porting applications from Unix to Linux

  To port applications to Linux start with an in-depth discovery process, examining Unix application compatibility and determining whether they're compatible with Linux. The hardware platform and operating system distribution also need to be ...  Continue Reading

• Linux cloning over the network using netcat

  Use netcat to clone Linux images over the network onto multiple servers with a series of simple Linux commands including tar, tee, and dd. This alternative to tools like Clonezilla does not require setting up a separate server.  Continue Reading

• Linux ext4 file system: Performance and compatibility

  The ext4 file system is now shipped with the most popular Linux distributions, but when should you use it and how do you optimize performance? Learn when to use the ext4 file system and how to set up your Linux system for maximized compatibility and...  Continue Reading

• Configuring GRUB 2: Tweaking the boot procedure in Ubuntu Server 9.10

  Configuring the new version of GRUB in Ubuntu Server 9.10 has changed. Learn how to install, apply changes to default settings and gain insight in the configuration files in /etc/GRUB.d/*.  Continue Reading

• Getting started with OpenVAS

  OpenVAS is an open source network security scanner, and version 3.0.0 has useful features for your Linux system. Learn how to install and set-up OpenVAS in your data center from source on a Linux server.  Continue Reading

• Designing a Linux virtual network for KVM virtualization

  Determine how to configure the virtual and physical network cards for optimal performance on a Linux network with KVM hypervisor. The best use of individual network cards and virtual network cards depends on the I/O of the virtual machines on the ...  Continue Reading

• Linux networking: Using ip tool instead of ifconfig

  If your server was configured manually, make sure the Linux network is set up with the correct IP configurations and the ip tool is being used to monitor your systems.  Continue Reading

• Finding password weaknesses in your Linux systems

  Getting through the security of your Linux systems might be easier than you think. Prevent unauthorized access by searching out unexpected password weaknesses.  Continue Reading

• Troubleshooting Linux networking problems

  Analyze and repair network problems related to your Linux system in three steps: determine if the network card is there, then check the hardware configuration and drivers. Some hardware also needs to be checked for module compatibility and tainted ...  Continue Reading

• Access and repair an ext3 file system with the superblock

  A damaged ext3 file system is accessible and repairable, thanks to the data within either the superblock or the superblock's backup.  Continue Reading

• Solving Linux server hangs stemming from kernel issues

  When Linux kernel issues cause functional machines to hang, determining the type of hang -- interruptible or non-interruptible -- is imperative to troubleshooting the situation.  Continue Reading

• How to solve logical volume management issues

  Excluding certain Logical Volume Manager (LVM) devices from startup scans and the manual activation of logical volumes are two pesky logical volume management issues. Find out how to resolve them.  Continue Reading

• Red Hat bolsters Linux for mainframes, tries to catch Novell

  In the Linux-on-the-mainframe market, Red Hat is catching up with Novell. If your mainframe shop is considering Linux on the IBM System z, this tip offers advice on choosing between Red Hat Enterprise Linux for Mainframe Computing and Novell SUSE ...  Continue Reading

• Should you pay for support on all Linux servers in your data center?

  Free Linux distributions are gaining popularity, but choosing whether to adopt paid or free Linux depends on your support staff's level of expertise and the workloads you expect the Linux distro will handle.  Continue Reading

• Troubleshooting Logical Volume Manager boot problems

  If Logical Volume Manager (LVM) boots incorrectly, logical volumes are inaccessible and you can't manage server disk space. In this LVM how-to, we offer some simple steps to troubleshoot boot issues with LVM.  Continue Reading

• Novell vs. Red Hat: How their Linux strategies affect your data center

  The leading data center Linux distributions -- Novell's SUSE Linux Enterprise Server and Red Hat Enterprise Linux -- are similar, and choosing the right Linux distribution can depend more on the provider's business direction.  Continue Reading

• Linux provisioning automation with Cobbler

  Learn how to set up and run, Cobbler, an install and provisioning server. It holds OS images and manages PXE booting, network configuration and deploys and installs them. It supports a wide variety of platforms including Red Hat, Ubuntu, Debian, ...  Continue Reading

• Five Linux commands you have (probably) never heard of

  Learn about five of the more rarely used Linux commands (logsave, diff3, pstree, nl and split) that are useful, with a description of each command's flags and options. These commands work well for file management, tracking, and output and process ...  Continue Reading

• How to install and get started with OpenQRM

  Learn how to install and use OpenQRM, a free and open source pluggable framework for automatic application deployment, management, and monitoring. It supports a range of virtualization tools and works with Nagios and Puppet.  Continue Reading

• Backing up the Linux master boot record

  The Linux master boot record (MBR) contains GRUB and the partition table, and to avoid crippling boot errors, it is a good idea to make a backup of it. Learn how to backup the MBR and how this effort can pay off when troubleshooting a Linux boot ...  Continue Reading

• Setting up cloud computing with Eucalyptus

  Cloud computing provides on demand provisioning of compute resources. Learn how to set up Eucalyptus on Ubuntu to perform your own cloud computing operations. Eucalyptus is available in source code, and packages are available for CentOS 5.3, ...  Continue Reading

• Comparing Unix versions: AIX, HP-UX and Solaris

  In this comparison of the top Unix versions, learn what distinguishes the file systems, management tools and virtualization products in Sun Solaris, Hewlett-Packard HP-UX and IBM AIX file systems.  Continue Reading

• How to install and use RRDTool to speed up MRTG monitoring

  When monitoring a large number of hosts or devices with the MRTG graphing tool, the system experience frequent CPU spikes. In this RRDTool tutorial, learn how to install RRDTool and convert MRTG to use RRD storage to avoid system overload.  Continue Reading

• Troubleshooting Linux boot problems

  If your Linux server fails to show the login screen at startup, you have a boot problem. Learn some tricks on how to diagnose and fix a Linux server boot problem from Grub failure to init and runlevels.  Continue Reading

• Configuring YUM on Linux

  YUM is a package manager for RPM systems, it is made to update groups of machines without having to update each specific RPM. Learn how to configure it using yum.conf and get some basic commands. Yum allows use of a single command to update all ...  Continue Reading

• How to install and configure MRTG, an essential sys admin tool

  Multi Router Traffic Grapher (MRTG) is an essential tool that allows systems administrators to monitor and graph network traffic and more. In this tutorial, an expert explains how to install and configure MRTG on Solaris 10.  Continue Reading

• Recovering your Linux server with a Knoppix rescue disk

  Learn how to recover data on your Linux server if it doesn't boot properly using Knoppix, and how to mount the Linux file systems on your server with step-by-step instructions. How to troubleshoot and interpret server data from the fdisk -l command ...  Continue Reading

• Top 50 universal Unix commands

  Learn about the top 50 most helpful Unix commands for administrators out of the thousands that exist. Use case examples are provided, along with links to other resources.  Continue Reading

• The Ext4 file system: A real improvement in Linux file storage?

  The Ext4 file storage system is now integrated into the Linux kernel and supported by the major distributions. Should you switch from your Ext2 or Ext3 set-up? With complete backwards compatibility, there is little reason not to make the jump ...  Continue Reading

• Keys to successfully running Samba in a production environment

  Running Samba in a heterogenous production environment with Linux/Unix and Windows systems is critical to business. Learn best practices for configuration, backup, and support. Proper implementation of change control, keeping an updated version of ...  Continue Reading

• Capacity planning tools tutorial for Linux and Unix

  Effective capacity planning is a proactive way of ensuring that your data center servers will not prematurely run out of space or horsepower. Learn the tools available to help you, both native to Linux and Unix platforms including Solaris, Red Hat, ...  Continue Reading

• A look at real-world exploits of Linux security vulnerabilities

  From unprotected NetBIOS shares, null sessions in Samba, to poorly configured FTP servers, your Linux system may be open and waiting for hackers. Learn how hackers can get into your Linux servers through these weaknesses and what you can do to ...  Continue Reading

• Five common Linux security vulnerabilities you may be overlooking

  Contrary to popular belief, Linux has security risks, that if not addressed can lead to malicious attacks of your system. Linux system administrators need to make security vulnerability testing a priority.  Continue Reading

• Using OpenSSH for secure network tunnels on Linux

  SSH is secure enough to be used across nonsecure private and public Internets. Learn the basics of SSH execution and how to implement and optimize SSH tunnels with Linux. SSH tunneling features allow remote traffic to be sent through the tunnel, ...  Continue Reading

• When to use SELinux: An introduction to security-enhanced Linux

  Confused about security-enhanced Linux (SELinux)? Find out what it is and how and where to implement this Linux security system. Ken Milberg explains its origins and provides some good advice for implementing the system in your Linux distribution ...  Continue Reading

• When to use Solaris vs. Linux: Operating system comparison

  When should you go with Solaris and when should you go with Linux? What about OpenSolaris – what is it exactly and where does this fit into the mix? Ken Milberg describes the advantages of the three operating systems, and suggests how each may...  Continue Reading

• Linux distributions ranked for speed, security, support, performance: Whirlwind Tech Tour

  How do Linux distributions compare in terms of performance, support services, security and speed under different enterprise conditions? Linux experts compare Red Hat Enterprise Linux, Novell SUSE Linux Enterprise and Ubuntu against these criteria.  Continue Reading

• Comparing blades with rack servers on price, performance

  Are blades or rackmount servers more cost-effective? Several experts weigh in on the factors to consider, including space constraints, power consumption, and performance.  Continue Reading

• Ensuring server time synchronization with NTP on SLES

  Synchronize your SUSE Linux Enterprise Server times using NTP time server. Two servers are recommended for enterprise situations, as redundancy will save the day in case of a disaster.  Continue Reading

• Repairing SUSE Linux Enterprise Server using a Rescue CD

  SUSE Linux Enterprise Server offers a Rescue CD for repairing the system if your hardware causes a crash at reboot. This tip shows you how to use it.  Continue Reading

• Which database is best for multiple platforms: Windows, Linux and Unix

  Linux expert Ken Milberg offers advice on database selection for the heterogeneous data center, and recommends Oracle based on market share, support and technical abilities.  Continue Reading

• How to troubleshoot RHEL performance bottlenecks

  This tip provides a step-by-step approach to application-tuning, troubleshooting bottlenecks and enhancing performance on RHEL 5 systems.  Continue Reading

• Using OpenSSL to create and manage certificates

  Establishing an independent certificate authority with OpenSSL enables you to create public key certificates and to verify that these public keys are authentic and that email messages are secure.  Continue Reading

• Creating an installation server for SUSE Linux Enterprise Server

  When installing multiple SUSE Linux Enterprise servers, using an installation server can facilitate the process. This tip details how to create an installation server for SUSE Linux Enterprise Server 10.  Continue Reading

• Build your own iSCSI SAN appliances, save money

  An open source storage area network (SAN) is a flexible, highly redundant failover option for the budget-conscious. But consider requirements like iSCSI, DRBD and monitoring software  Continue Reading

• Solaris system performance tuning

  Solaris 10 systems need tuning and optimization in order to give the best performance given a certain system configuration and workload. The methods mentioned here are applicable to earlier Solaris versions and some other UNIX-based operating ...  Continue Reading

• How to use Unix file system snapshots

  File system snapshots are a great Unix systems administration tool. Learn how to use them to copy database files with minimal downtime.  Continue Reading

• Clonezilla: Not such a monster with expert guidance

  If your system crashes, the image server Clonezilla on Ubuntu can circumvent time-consuming troubleshooting procedures during recovery.  Continue Reading

• Settings to optimize an XFS file system

  To improve system performance, explore this guide oin XFS file system program settings.  Continue Reading

• Are you prepared for the Unix 2038 problem?

  All 32-bit Unix/Linux-based systems store the system clock time internally as the number of seconds since the "Epoch." The latest time and date that can be represented as seconds-since-the-Epoch in that 32-bit signed integer is 3:14:07 UTC on ...  Continue Reading

• How to use XFS management tools

  While XFS is a valuable file management software, a strong understanding of its management tools is central to reaping its benefits. Learn how to use XFS commands from an expert.  Continue Reading