Rsyslog central logging with LogAnalyzer

Rsyslog central logging with LogAnalyzer

After reaching a number of managed servers a central log-collecting and -analyzing solution is inevitable.

As most Linux systems come with rsyslog by default, it’s an easy way to use it to redirect some or all our logs to a central log server.

We’ll need only a few modifications on the client side, and the setup of an rsyslogd server on a new vps or on one of our current servers.

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How-To create your iptables firewall

Aim

When I first used iptables my aim was as simple as setting up a reliable firewall to protect my home network from unwanted traffic, and share my Internet connection to all the computers on the LAN. This article gives an easy example for such purposes.

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VMware – PowerCLI | Deploy Ubuntu/Debian VM from template and set basic parameters

Today it’s a common task of an operator to create a new virtual machine quickly for a customer or for testing purposes. Scripting the setup and the basic customization can provide a good basis for automation, mass deployment or integration with self-service portals as well.

The following example intends to give hints on basic usage of PowerCLI and a simple checklist: which basic parameters should be customized for a newly deployed VM.

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How-To create backups of running vApps in VMware vCloud version 5.1 and earlier

With vCloud version 5.5 the Director (web GUI) got a bunch of useful features. One of them is Cloning Running vApps: http://www.vmware.com/files/pdf/products/vCloud/Whats-New-VMware-vCloud-Director-55-Technical-Whitepaper.pdf page 9 – 2.2.3 Clone vApp with Memory State

With older deployments of vCloud administrators still have to use the REST API to create these hot-clones. From the vCloud Director the only option to clone a vApp is to stop that first, which method is simply unacceptable in production environments.

When developing automated backups, or auto deploying vApps/networks the REST API-based scripts come handy even with newer versions.

Let’s take a look at the API through a few simple examples.

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More is not always better – CPU ready in VMware vSphere

You might have a situation, when your 2 vCPU webserver is having a high load (although CPU usage in MHz is normal).

In this situation most administrators would add extra vCPUs to the server, and expect to have an enhanced performance.

Unfortunately the additional vCPU can actually degrade performance. Let me explain why.

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Migrating a Linux system to virtual machine with rsync

Server consolidation ratio grows steadily. But how can we migrate our current systems to a virtual environment in an easy way?

Besides vendor specific solutions, for Linux systems there’s a simple and quick way to migrate a server to another machine (in most cases to a VM)

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