Sharing Our Passion for Technology
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    Hard Drive Sustainability

    Your hard drive with very important family pictures has just failed, and now all data is lost forever. Could you have prevented this from happening? This article is a quick walk though of how to detect hard drive errors before the disk is unusable. At the end of this article, you...
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    How RAID 5 Works at a Bitwise Level

    RAID 5 is a pretty magical thing overall, though a large portion of its magic lies in how it works on a bitwise level. But before I get into the bitwise sorcery, I’d like to briefly explain what RAID5 is. RAID stands for Redundant Array of Inexpensive (or Independent) Disks....
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    The Easiest Way to Organize Zimbra Email

    If you’re like me, receiving 30-40 emails is par for the day. Because Source Allies provides consulting services for companies wishing to implement or better take advantage of Zimbra, it is also the mail server we use at our company. Zimbra has incredible search capabilities, but my OCD tendencies still...
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    Ubuntu Live Network Boot using PXE

    Requirements Linux server with NFS (or compatible) TFTP server DHCP server syslinux / pxelinux files To simplify these instructions we are going to make the following assumptions. DHCP server is 10.0.0.2 TFTP server is 10.0.0.3 NFS is a Ubuntu server at 10.0.0.4 In reality it’s likely your TFTP and NFS...
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    Creating Services using SMF in OpenSolaris

    OpenSolaris has by far, one of the best service management interfaces that I have used. Below I am going to go over a simple way to turn in shell script into a service managed by the OS. Step 1: Create the Service Manifest <?xml version='1.0'?>; <!DOCTYPE service_bundle SYSTEM '/usr/share/lib/xml/dtd/service_bundle.dtd.1'> <service_bundle...
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    Who Bound Port 8080

    "Port 8080 required by Tomcat v6.0 Server at localhost is already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number(s)." I have...
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    Unplugging an LVM partitioned USB drive

    Recently I had the heartbreaking experience of having to reboot a Linux server. Normal usage should almost never require you to reboot the OS like you have to so frequently in Windows. In this case I had an external USB drive partitioned with LVM humming along on a Linux server....
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    Apache/Tomcat with Failover and Load Balancing in 20 minutes or less...

    In order to get this done, you’ll need Apache, Tomcat, and the MOD_JK connector library. I’ve included the Windows binaries below, as I’m writing this blog post from a Windows machine. Feel free to swap out these downloads with whatever RPM, YAST, APT, etc. commands you want. Also, you’ll need...
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    GlusterFS Replication for Clustering

    I recently was searching for a way to simulate shared physical storage in a VPS environment for clustering purposes. In an enterprise data center we can expect some type of SAN available to provide shared physical storage. GFS is a simple solution in this case to create a shared file system that...
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    Using Conga Web Configuration with Red Hat Cluster Suite

    Overview Red Hat Cluster Suite provides high availability and clustered storage for RHEL platforms. Unfortunately the configuration management for each node can be tedious as the /etc/cluster/cluster.conf file must be copied to each as changes are made.  Conga makes life a little simpler. http://sourceware.org/cluster/conga/ Conga provides a client/server architecture for cluster...