Technology Errors

createdb: database creation failed: ERROR: source database “template1” is being accessed by other users

When attempting to create a new database on a PostgreSQL server running walmgr, which is part of SkyTools by Skype Developers, for real time failover I received an error. Initially I was a bit baffled by the error however I remembered after racking my brain for a little bit that you must stop walmgr’s syncdaemon when adding a new database. Below are more details about the error as well as how to stop walmgr’s syncdaemon and then create the new database.

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Technology Insights

Create A New Logical Volume In A Logical Volume Group With Space On A Linux Server

As noted in a previous article I have been working on a couple new Linux servers with a minimal install of CentOS on them. The /var, /usr, and / directories each were configured with 2GB of space within a logical volume group that has 1TB of space available. I first expanded the /var and /usr directory from 2GB to 20GB and then expanded the root, or /, directory from 2GB to 30GB. Once all three of these directories were expanded I next needed to create a new logical volume group and a partition to hold PostgreSQL data. Use the information below to create a new logical volume, format it with the ext3 file system, mount it, and configure it to be mounted automatically upon the next boot of the server.

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Technology Insights

Remove A Logical Volume From A Logical Volume Group On Linux

While testing various settings and other changes with logical volume groups I had created a test logical volume group that I no longer needed so I needed to remove it. When using the below information be aware that any data contained within the logical volume group will be gone after the logical volume is removed. The information below explains how to first list the current logical volumes with lvscan and then how to remove a specific logical volume with the lvremove command.

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Technology Insights

Expand A Partition That Is Part Of A Logical Volume Group While Server Is Running

I recently had a couple new CentOS Linux servers brought online at a colo that a company I work for uses. I had the colo do a very simple install of CentOS so I could handle the details without having to remove a bunch of packages we didn’t need. The servers have two one terabyte drives installed in a RAID 1 configuration which provides us with one terabyte of usable disk space and upon initial configuration had a logical volume group created with three logical volumes. Each of the logical volumes, which included /var, /usr, and /, only had two gigabytes of space so I needed to first expand those logical volumes and later will be creating a large logical volume used for database data. Below I describe expanding already existing logical volumes when there is room to grow in the logical volume group.

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Technology Insights

Mac OSX 10.6 Sticky Notes Shortcuts

I love notes. I am the kinda guy that puts notes every where including all over my computer desktop. Mac has a really cool application which is called sticky notes. I have been using it for a few weeks now and I really like it. It has multi colored notes so I can keep my tasks color coded. Today I discovered a really neat feature when using sticky notes.

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