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Entries from February 2009

Even the clouds come down to earth – cloud services crash just like everyone else sometimes

February 24th, 2009 · No Comments

During our weekly sysadmin call this morning several of our experienced sysadmins quickly pointed out that clients seeking very high up time should not necessarily look for it on the cloud.  I couldn’t believe it, but almost as an omen, this story came on my RSS feed from Webware:  Google apologizes for email outage
Outages pose [...]

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Tags: cloud computing

Ubuntu 9.10 “Karmic Koala” will use Eucalyptus for your own cloud computing solution

February 24th, 2009 · No Comments

Mark Shuttleworth announced last Friday that Ubuntu 9.10 will be named Karmic Koala, and also presented what we should expect from the future version of Ubuntu:

the desktop version will have a new look (more beautiful)
on the server side as everybody these days Ubuntu’s future will be targeting the “cloud”. They will have official supported [...]

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Tags: cloud computing

Nagios: How to check if remote process is running

February 24th, 2009 · No Comments

We have a monitoring server running Nagios and we needed to add checks for Nginx process on a new server.  Basically, you only need to install NRPE to monitor services, processes, disk space, load, etc on your remote machine.  Check the NRPE docummention for complete reference and here’s a quick NRPE installation guide for Debian.
For [...]

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Tags: Nagios · monitoring

Best definition of cloud computing – to date

February 23rd, 2009 · No Comments

best definition of cloud computing according to Berkeley

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Tags: cloud computing

Cloud Computing Chart

February 19th, 2009 · No Comments

Here is a great chart from James Maguire article “Five Companies Shaping Cloud Computing: Who Wins?”, that provides an overall comparative look at the current vendors in cloud computing:

While you are here you go ahead and read his article also as it has some good information on the future of the “big five” in cloud [...]

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Tags: cloud computing

Cloud computing scenario’s for database servers

February 17th, 2009 · No Comments

We’ve been investigating the possibilities of using cloud computing for our clients. Especially Amazon EC2 has the potential to be be really effective in offering flexible, pay-as-you-go computing. From my own perspective I have been looking at how to use cloud computing in combination with MySQL and I must say that I’m a bit sceptical [...]

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Tags: Down Time · MySQL · Performance · Replication · hosting

Cisco ASA 5505: Active/Standby Failover Configuration

February 17th, 2009 · 8 Comments

The ASA 5505 is the smallest (and cheapest) solution from the current Cisco hardware security appliances. Still, if we have the proper software license (like Security Plus for example) we can use the ASA5505 to setup rather complex solutions. This post will show how we can setup a pair of ASA5505 in failover configuration, solution [...]

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Tags: CLI · Security · cisco

HowTo recover from a corrupt rpm database

February 10th, 2009 · 8 Comments

RedHat based systems (rhel/fedora/centos) use rpm/yum to install and upgrade packages. If the rpm database gets corrupted in some way it will break all the functionality of rpm and other tools that rely on it like yum for example. We have seen this either showing some errors on the console, or most frequently just by [...]

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Tags: Centos · sysadmin

Upgrade to Java SE 6 update 12 on Fedora 10

February 9th, 2009 · No Comments

After our ASA units were updated to the latest version of ASDM my Java client would no longer connect to ASDM. An upgrade to the latest version of Java was in order. Since fedora yum repository does not yet offer the latest version of Java I downloaded the latest rpm variant of JDK from http://java.sun.com/javase/downloads/index.jsp
The [...]

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Tags: Installation · desktop

Extending the slow query log

February 4th, 2009 · No Comments

Andy posted some very good links recently to video’s on how to optimize your web site. Although I spend more time optimizing the database you always have to go where the actual performance is lost. For MySQL the place to check for performance issues is the slow query log which I have mentioned in earlier [...]

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Tags: MySQL · Performance