Anyone who has added and removed multiple disks from a RedHat server knows very well that your disks may not always enumerate exactly the same way after a reboot. You then have to resort to mounting up your filesystems to a temporary mount point to see exactly whats in them, and were they really need … Continue reading RHEL- Find UUID of Hard Disks
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e1000 device eth4 does not seem to be present, delaying initialization
The moral of the story today is beware of servers that have had a long history of changing networking configurations and network interfaces, as you never know what you are going to run into. While working on a RHEL 5.4 box and attempting to make few minor changes to eth4 and up the interface, I … Continue reading e1000 device eth4 does not seem to be present, delaying initialization
Meld — Graphical Merge and Diff Tool for Linux
Meld is a very nice tool for those who cant stand to use diff to compare the differenced between two text files. If you have either the rpmforge repo or the epel repo configured you can install it via yum. Note: I am using Centos 5.4 which is a bit dated, so you might find … Continue reading Meld — Graphical Merge and Diff Tool for Linux
Linux Load Generating Script
Nice little Linux load generating script courtesy of unixfoo. http://unixfoo.blogspot.com/2008/11/linux-cpu-hammer-script.html  More information on stress testing Linux can be found here There are also several additional stress test tools available for RHEL/CentOS in the Dag repo, such as stress, hammerhead, and fio,
How to Configure NTP in a RHEL/CentOS Vmware Guest
HourglassSuccessful time keeping in a Virtual Machine can be a bit confusing. At times I have been told to use Vmware Tools to sync time between the Guest and the Host, and at time I have been advised to avoid this functionality and use NTP. The following information is direct from a VMwareKB article (updated, 4/16/2010) so I am going to follow their lead on this and use NTP exclusively.
Redhat I/O Scheduler Configuration in a Virtual Machine.
The Linux kernel controls disk I/O scheduling, and is responsible for its optimization. One of the ways that it does this is via an I/O elevator to reorder and schedule pending I/O requests in order to minimize the time spent moving the disk head. This reduction in movement results in a reduction in disk seek time which in turn, maximizes hard disk throughput.