Nov 2nd, 2009 |
I can’t tell you how many conversations I’ve been sucked into where the office tree hugger started ranting at me about how much energy data centers use to run the servers and air-conditioning. Even people “in the know” look at data centers as a black hole for power and cooling, but I try to point out that data centers also serve a very important function rarely mentioned. The tendency for departments to keep their servers close by has the unintended consequence on building management’s ability to shutdown office buildings on weekends, evenings and holidays.
Let’s look at where I work, the University of Hawaii has long fought a battle trying to shutdown lights and air-conditioning in our office buildings to save energy. However, departmental servers overheating during those shutdowns have long thwarted this endeavor. The University of Hawai’i like so many other organizations is making the move to change this by upgrading their server hosting facilities to remove this energy saving barrier. Upgrades like IP KVM’s, power control, environmental control, remote media and service processor aggregation have all made massive progress in the last couple of years removing the differences between remote and local access. Now start adding in the ability to reduce the need for a third shift and we’re talking about some pretty big HR costs savings to add to the energy and cooling savings possible by office shutdowns. Here’s a few of the big changes I’ve had the privilege to see first hand:
IP-KVM aka keyboard+video+mouse switch box:
Getting to the console of the server is one of those things that just needs to happen periodically for things like bios upgrades, system regens, and many other important functions and the number one reason why departments don’t want to let their servers out of their offices. Originally these systems forced you to install specialized applications onto your machine with video that would require that I manually refresh the screen just to see what was actually there. Now those clients are either active-x (Windows) or Java based plug-ins for browsers and in most cases even ride over SSL for either the entire data stream or at the least the login process. What’s just appeared on the horizon is some smaller IP-KVM’s that utilize VNC (virtual network computing) that’s already available on just about every computing platform available today. Some important basics are:
- variable color pallet to reduce communications overhead on slow links
- ability to send special key combinations like control-alt-delete and macros to accommodate non-Windows machines
- Ability to remote mount media on target machines to cut down on data center physical access needs
- For larger installations you’ll probably need Radius and/or LDAP authentication. Low hanging fruit is probably Active Directory’s flavor of LDAP
*NOTE: Avocent attempts to auto-synchronize the KVM and remote PC mouse, but in some cases you’ll need to tinker with refresh rates to get it to behave. Raritan forces you to deal with a dual cursor and a menu to switch back and forth between dual and single cursors. While a bit of a pain point, it does solve the cursor sync issues that creep up and also allows Raritan to work with just about any browser and OS.
Secure Serial Console:
Terminal or serial servers have been around for a very long time and have gone from only handling simple serial control to full modem control and now SSH tunneling for encrypted serial access. One of the newest features to catch the eye of many data center managers is the ability to Internet connect physical ports on the serial console server (or whatever you feel like calling them since all these vendors are constantly trying to correct my terminology) to virtual serial ports on workstations. With this type of connection, you can utilize applications that were never designed to work over a network, but still present the serial connect its software wants. For instance, there exists LOTS of temperature and humidity probes on the market, but not all of them work over a network, the ones I’ve tried all work just fine. More to the point, this type of function gives me the ability to yank data off things like building environmental systems without having to go into those horribly noisy rooms.
Interop has long had a physically separate layer 2 network (as opposed to routed since this means everything is much simpler) that we call “Access Ethernet”. We connect serial console servers, IPKVM’s, webcams, environmental sensors and other mgmt (aka non public) devices. This way we can always get to the serial consoles on the switches, routers, UPS’, etc regardless of whether the main network has become trashed by a worm or virus.
Smart Power Strips or Power Distribution Units (PDU):
It’s all about control and being able to remote power down or power up problem units is a pretty big deal. I’ve managed to wedge quite a few machines in my time that could only be solved by a hard reboot with the BRS (aka Big Red Switch). Having the ability to power down a problem child is tied directly into IP-KVM access on quite a few systems. The added benefit is that you can also tie in security to prevent someone from killing your data center through a PDU backdoor. Might I suggest putting the mgmt interface of the IP-PDU onto a management network?
Regardless of whether you adopt one or all of these systems, they’re all about reducing the number of time you “open the refrigerator door” by keeping warm bodies out of the data center as much as possible. Now how about other ploys to make better use of you existing cooling systems?
Bus Bar Power Distribution Systems:
The StarLine system by Universal Electric is one of the few bus bar power distribution systems I’ve run across, and with systems that can accommodate upwards of 600amps of 3 phase, they were originally designed for traveling cranes in places like foundries. However, when I had a chance to see these in action at the University of Hawaii SOEST data center, I was amazed at just what getting power whips out from under our raised floor could do. Not to mention that we can now legally swap out breakers, receptacles and such in the overhead power tap boxes. Though a bit spooky the first time you live swap a tap box in, it’s fully UL rated and allows us to rid ourselves of ugly whips that take up way too much space in our cable racks.
In-Row or In-Line computer room air conditioning (CRAC) systems:
American Power Conversation (APC) has three different in-row variants that allow you to put the cooling right next to the heat load, dramatically increasing in the efficiency of the data center cooling system. Traditional CRACs typically pull in data center air, do a heat exchange using building chill water, and then pressurizes the raised floor. To provide cold air to a heat load, you simply replace a solid floor tile with a perforated tile. The downside is that these tiles have typically just had a whole bunch of holes drilled in it with no thought to directing the cold air to where it’s needed. Anixter recently showed me a floor tile with vanes (similar to those Vornado fans) to direct the cold air. However, even with this innovation, you still haven’t solved the problem of a hugely inefficient duct system where odd corners each up your cooling capacity.
In steps the concept of in-row computer room cooling that was first shown to me by the folks at APC. Their first effort was a “top hat” affair that contained the hot exhaust air so that a CRAC could suck it up and get better efficiency. However, the newer units are thin rack shaped units placed right in line with the racks of equipment. Called the RP, RC and SC series these systems leverage the three most common air-conditioning technologies available today.
APC InRow SC: I call these an air-to-air system since this 1/2 rack width system pulls in cool air and exhausts hot air. Similar in operation to a window air-conditioner, this 7kw unit is what I use to cool my lab racks. Designed to leverage a return air ceiling, it even comes with a ceiling tile template and is perfect for telecom closets with gear.
APC InRow RP: These refrigerant based systems are a full size rack, but it contains the compressor and heat exchange equipment with only a condenser sitting outside. Using the new environmentally friendly refrigerants that replaced Freon, it should be pointed out that at these pressures, you need to have a air-conditioning tech that’s familiar with silver solder and high pressure systems.
APC InRow RC: This system uses the building’s chillwater system and in our case our air-conditioning engineer designed us a great water manifold to save a bit of space. These 20kw units use nearly 1/2 the power our old system used and provides quite a bit more cooling capacity than our old CRAC. Rebate here we come.
So did I just mention rebates? Check your local power providers…I just betcha they’ve got some sort of rebate program either in place or in the planning stage to encourage folks to do computer consolidation. Getting servers out of department offices means you can shutdown the aircon in the evenings and weekends. It also means that you can go to larger more efficient UPS systems for the data center. In addition, you can utilize things like those freezer curtains that you seen in meat markets to contain the hot or cold air in a single place. The gist is that if you contain the air and don’t let it mix, you really kick the efficiency of your data center cooling system. Check it out, that upgrade may be partially offset by rebates.
Go green….
