Setting up a Postgres test cluster in vagrant

Most of the time its fine to test things out on your local machine and local installation of Postgres but often, you want more flexibility, the ability to quickly reset to a known starting point and the ability to try out different and more complex server architectures.

That is where Vagrant comes in. I use it to quickly set up Postgres clusters at different versions and different configurations.

You can find all of these in my repo at

For example here is a set up to allow you to set up a 3 node cluster with 1 leader and 2 followers all on postgres 9.4 and using replication slots:

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How to Install Virtualbox Guest additions for Oracle Enterprise Linux 6

  This tutorial leads straight on from ‘How to install Oracle Enterprise Linux 6 on Virtualbox’ and assumes that you have a clean install to work from. If you haven’t installed OEL6 or have any problems with this tutorial, I recommend that you follow that tutorial before this one. So, in virtual box, Guest additions gives you some cool …

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How to install OEL6 on Virtualbox

Virtualbox is Oracle’s solution to visualization and as such it is very powerful. It is similar to VMware as it has much the same capabilities and you can run servers through it on an enterprise level. For the purposes of experimenting with operating systems and learning Oracle, it gives us some amazing benefits and makes …

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Cleaning up a failed Oracle 11g grid infrastructure install.

Unfortunately, the installer or more specifically the script for the Oracle 11g grid (Clusterware) installer can be very flaky.   If it fails and you need to fix something or rerun it for any reason, it will fail the next time if you have not cleaned up the install by de-configuring CRS. I also …

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Using files on a shared drive as disks for ASM (on RedHat Linux)

Firstly, you need to create files padded to the required disk size. So if you want 4 1Gb files you could execute the below commands on shared storage: dd if=/dev/zero of=/SHAREDDISK/asmDisk1-1 bs=1024k count=1000 dd if=/dev/zero of=/SHAREDDISK/asmDisk1-2 bs=1024k count=1000 dd if=/dev/zero of=/SHAREDDISK/asmDisk1-3 bs=1024k count=1000 dd if=/dev/zero of=/SHAREDDISK/asmDisk1-4 bs=1024k count=1000 dd creates your file, ‘if’=/dev/zero gets null …

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Manually upgrading to 11g

You can directly upgrade an Oracle database from version or higher, directly to 11g Upgrade Process. Open database in Upgrade mode:      startup upgrade Pre-Upgrade information tool:      utlu111i.sql Precursor to the upgrade. Generated report on required  and recommended changes to make.. Generally increasing tablespace sizes or remove parameters. Upgrade script:   …

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