san

A customer rose a support case with a problem on his Master-Master set-up. The 2^nd Master claims to have a problem:

Be careful when using SAN (Storage Area Networks) or similar shared storage solutions (and any other virtualization, consolidation or cloud solutions).

This week it happened again: A customer called us because he had some troubles with his on-line shop (note the date!). Everybody in his company complained that the databases are answering slowly.

Vorsicht bei der Nutzung von SAN (Storage Area Networks) oder ähnlichen Shared Storage Lösungen (und allen anderen Virtualisierungs-, Konsolidierungs- oder Cloud-Lösungen).

Or an active-active failover cluster à la VMware.

Today I have learned about a totally crazy/cool looking architecture where the expensive VMware ESX server was replace by a free/cheap VMware Workstation version in combination with DRBD.

Basically DRBD we name the poor man's SAN and that is exactly what this customer is doing. He replaced the SAN with DRBD and now he can easily move one VMware instance to the other host. Possibly it is not that flexible and powerful as an ESX Server but also not so expensive...

The architecture looks as follows: