Linux System Admins Blog

I noticed lots of email being relayed on one of our shared hosting server, CentOS5 with Cpanel and running Exim, and the strange thing is that the email server (MX) for these accounts are pointing to Google (GoogleApps), and we have correct entries for localdomains and remotedomains for these account. The relayers (‘From’ server/address) [...]

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Almost two months after RHEL5.4, Centos 5.4 was released on the 21st October. This version includes various changes into the virtualization field and it includes support for KVM (kernel-based virtual machine) hypervisor and the Xen hypervisor.
Also this release features many bug fixes and security updates, and should be an easy upgrade for users running centos5.x:
yum [...]

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If you are using a shared server, or just have a limited account on your company servers, you might not have access to your php configuration file php.ini (this is usually found under /etc/php.ini in rhel/centos and /etc/php5/apache2/php.ini in debian/ubuntu). Still, in many situations it might be needed to enable php errors in the browser [...]

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After a long development time, Centos 4.8 was finally released on the 21st August. This is a good thing that after the latest problems between the centos developers, they were able to pull this out finally and now be able to focus on the upcoming 5.4 release.
There are no major changes in this update, mostly [...]

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This is my second activity on using AWS – this time the use of EBS.
Objectives:

Format a new EBS (10GB) and mount it on a running instance of private AMI (created on first activity – add link/ref to old post)
Setup a MySQL server with the datastore on EBS partition
Setup the partition(EBS) to start [...]

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Are you often waiting over 1 minute to get a ssh prompt? This can be caused by several things however more often then not is a missing PTR record for server address and enabled GSSAPIAuthentication in ssh_config. GSSAPIAuthentiction is Kerberos 5 centralized authentication/authorization mechanism that relies on resolving a hostname for proper operation, when it [...]

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Here’s my first try working with Amazon Web Services. Covered tasks are the following:
- getting familiar with AWS, specially EC2 and S3.
- working with EC2 instance using CentOS image – search, start/stop, and do some customization of an instance
- create AMIs (private) and start instance from it.
- S3 buckets – upload files.
I based my [...]

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In this guide i will provide the steps in moving Drupal sites with CiviCRM – with Drupal and CiviCRM in one or separate databases. I will outline the steps and sample commands but won’t give much details, so feel free to ask if you need any clarifications. Also, refer to my previous guide [...]

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Here’s my quick howto on installing GNUPG PHP Pecl extension (pecl docs) in Cpanel. Please note that this covers only the installation process and no further details on setting up gpg keys or using the function with extension or sample PHP scripts.
Installation process is very straightforward provided you met the requirements like php-pear, gnupg, [...]

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Anyone running centos/rhel x86_64 systems has probably noticed that redhat has a strange way to install a mix of i386 and x86_64 rpms on such a systems. This is how redhat is using the 64bit architecture in a mixed way to be able to support also i386 applications. This is completely different from how for [...]

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