Author: Steven Protter

Maria-db(mysql) two node installation with galera data replication

This is the first step toward unsupported installation of the NDC, New Data Cloud. To get the commercial version with full support, click here. This document takes you through the installation and creation of a two node database installation. This install was done in google compute engine but with the right band width will work […]

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Use TCP wrappers with care

Real life story.   DMZ based server dedicated to SFTP was configured with sshd rules in /etc/hosts.allow sshd : ALL@16.89.97.*:ALLOW sshd : ALL@14.251.*:ALLOW sshd : AAL@208.94.61.*:ALLOW Should have been: sshd : ALL@16.89.97.*:ALLOW sshd : ALL@14.251.*:ALLOW sshd : ALL@208.94.61.*:ALLOW That network was the firewall to the outside world. The end users were inconvenienced and the firewall […]

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Making sure what is configured to mount is mounted

Here is a script that uses some advanced awk commands to check that what is configured to be mounted in /etc/fstab is actually mounted. #!/bin/ksh ######################################################################### # fsrootreserve #HPUX_SCRIPTS=/opt/depots/scripts/system_build/HPUX #COMMON=/opt/depots/scripts/system_build/COMMON # Load common environment . /opt/scripts/env/.scriptenv.linux # set total variable for reserve blocks tot=0         echo “. Checking mount status of all […]

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Centos Continuous Release with caution

Centos Continuous release is very easy to install. Download and install 1 rpm and you are all set. i386: http://mirror.centos.org/centos/6/extras/i386/RPMS/centos-release-cr-6-0.el6.centos.i686.rpm ( sha256: 9fc78d2d79abeb1513f0851d075a2860f5039fc8db3fb0db4c660252fffda894 ) x86_64: http://mirror.centos.org/centos/6/extras/x86_64/RPMS/centos-release-cr-6-0.el6.centos.x86_64.rpm ( sha256: bd55e1505caae2f78c306290d235b7f54833fcad5a9f1942b3cb54e28f7bfe73 ) But I urge caution. In my lab, I downloaded the 64 bit version and installed it. Then I ran the following command: yum -y update […]

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Network Channel Bonding (teaming) RHEL 6.0

This procedure did not actually change very much from RHEL 5.0. Knowing the changes however are pretty critical to getting it right. Gone is the Administrator’s friend and potential cestpool, /etc/modpprobe.conf Its replaced by anything you want to load in /etc/modprobe.d Naming guidelines? Who needs them. Name the file anything you want. Procedure: Still pretty […]

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