Virtualisation can introduce power and cooling challenges that can play havoc with a data centre, said the director of Emerson Network Power, Peter Spiteri.
Server virtualisation can reduce IT costs, enhance performance and improve data centre space utilisation, but it can also introduce power and cooling challenges than can limit an organisation's ability to realise the opportunities.
“The biggest concern is that, up until virtualisation consolidation, you could get away with a fair bit. The loading didn't need to be so perfect, it didn’t matter so much if the room wasn’t positively pressured," Spiteri said. "The big issue now is you can't get away with it; when you get a thermal runaway, the issues could be catastrophic.”
Speaking at the Kickstart media conference in Queensland, Spiteri warned companies considering virtualisation must take a holistic look at their infrastructure as well as the issues around consolidation and cost reduction in order to realise the benefits.
Consolidating servers often increases the power draw within racks and backup systems must be designed to handle the increased capacity, reliability and redundancy that virtualisation provides. Heat can also be an issue, particularly for blade servers which concentrate it within a small space. The resulting ‘hot spots’ may need specialised high density cooling.
“Otherwise, you could end up with an entire data centre room with two servers in each rack,” Spiteri said.
The warning signs
Signs your infrastructure may not be ready to for the increased power and cooling requirements for a planned consolidation or virtualisation strategy.
- You can neither control access to your racks nor adequately control additions or changes to equipment.
- You haven’t calculated power and cooling demands for the consolidated environment.
- You are using line interactive UPS and power has dropped when the UPS failed.
- Critical power systems consist of multiple small UPS units rather than a centralised UPS system.
- You have difficulty keeping temperatures in the room below 25.5 degrees Celsius (78ºF) before new equipment is installed.
- You have no way to target additional cooling to racks with densities above 5 kW.
- There is no way to monitor power and cooling system performance for trading and be alerted to potential problems.
- You have not updated service level agreements.