What switched PDU should I buy?

Our latest firewall/VPN firmware upgrade left CPU usage at 100%. A malfunctioning DHCP-Server means people aren't getting IPs. I have to pull the plug to restart the firewall. What size switched PDU do I get?

With equipment freezing after a firmware upgrade, you clearly need to resolve the fundamental lock-up problem in the firewall and VPN. Until then, power cycling the IT equipment will have to suffice.

Most power distribution unit (PDU) manufacturers offer products with per-outlet switching. Since you need to cycle only one device in each data center location, and switched PDUs are expensive, buy the smallest one you can get. Alternatively, buy a switched PDU with enough outlets for your full rack of equipment and put all the IT systems on the switchable PDU whether boxes need switch control or not. This method also allows you to keep unused receptacles turned off so nothing connects to them without authorization.

PDU outlet switching occurs remotely via network connection, which makes it really simple to accomplish power cycling to fix your issue. However, be cautious of two things:

It is not necessary to use a high speed network port for these PDUs. If you have only one PDU in each location, that will be your only reasonable choice, but if you have intelligent PDUs that measure power usage or other parameters such as rack temperature, consider installing a separate basic network to support those devices.

Vendors that offer switched rack PDUs

APC by Schneider Electric has several models.

Raritan makes switched PDUs as well as inline meters and rack transfer switches.

Tripp Lite offers UPS, PDUs and other data center equipment.

Western Telematic Inc., also called WTI, has network-grade PDUs.

Anything that is remotely accessible for IP addressing is also vulnerable to unauthorized outside access. If you weren’t dealing with remote offices, I would suggest keeping these PDUs on a strictly internal network, but in this case external network access is the only choice. Include all the security measures reasonably possible.

About the author:
Robert McFarlane is a principal in charge of data center design for the international consulting firm Shen Milsom and Wilke LLC. McFarlane has spent more than 35 years in communications consulting, has experience in every segment of the data center industry and was a pioneer in developing the field of building cable design. McFarlane is one of several regular contributors to SearchDataCenter's Advisory Board, a collection of experts working in a variety of roles across the IT industry.

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