I’m sprucing things up in the studio (basement), which includes removing most light stands and tripods. They’ll be attached to the ceiling instead, and with that comes re-wiring everything. Also, upgrade of a couple of full-size Blackmagic Studio Cameras (gen 1) to the much smaller and lightweight Micro Studio Camera 4K G2. Unfortunately, whereas the old BMSC devices have SFP slots for fiber connectivity, the BMMSC G2 does not.

So I’m also using a couple of Blackmagic Mini Converter Optical Fiber 12G modules with the cameras, but as with the cameras they require power which can’t be provided by fiber. (I did look at structured cable, but it wasn’t worth it.) To keep things somewhat neat and tidy, I decided to provide power remotely using 4-pin XLR cables going into custom splitter boxes with 3 barrel jack outputs. That’ll run the camera, converter, and a small LCD monitor if necessary.

Mostly this video ended up being about the adapter box, and I didn’t get into the fiber converter as much as I intended to from the outset. That’s because the whole project got a bit sidetracked by the power supply not working out of the box. I’d picked up a Core SWX Cube 200 Power Supply from B&H, which is supposed to put out 14.3V constantly, but was putting out 16V occasionally when I banged on it. Just a faulty unit, I suppose. Might return it or investigate further.

In a subsequent video I’ll go over the actual setup of the cameras using the adapter boxes, as well as the fiber converter (and hopefully a working high-amp PSU).

As usual, nothing in this video was sponsored and I’m not promoting anything. I paid for all this stuff out of my own pocket, for my own reasons.

I wanted more control over the lighting in my basement “studio”, and decided to invest in a few dimmer/switch packs as well as a USB rack-mount DMX controller.

Obviously if you’re reading this years later that will seem like a terrible price, but as of now 600GB SAS drives are selling for about $30 each (used). So it’s roughly $720 worth of drives alone. The SC220 is basically an MD1220 in sheep’s clothing (though sheep are generally naked so who knows), and those are selling for about $120.

Like I said, a great deal! But there was one question that needed answering: Did the Dell-branded Compellent HDDs have some kind of special firmware that rendered them useless with a standard RAID or JBOD controller?

I found posts online that told me the chassis was a safe bet, as it would essentially work as a DAS with any standard HBA or RAID controller. But, having had some bad luck accidentally ordering NetApp drives*, I was nervous about pulling the trigger on this particular auction.

* Most — if not all — NetApp drives have 520-byte sectors and weird firmware which renders them incompatible with most SAS controllers. They’re usually the cheapest disks around, but that’s because they’re basically worthless for the average Joe/Joette.

Cavalierly, I decided to scream “YOLO” to no one in particular and hit “Buy it Now”.

Shortly afterwards, I hooked up the SC220 as-shipped to an HP DL580 with a P812 controller and … it recognized the individual drives and let me create an array! The array works just fine.

The error given has no effect on the operation of the array. The P812 also has an HP D2700 DAS shelf attached with redundant cabling, whereas the SC220 is single-cabled for testing. Because it’s a non-critical error, no user input is required to proceed.

The moral of the story being that, should you find a good deal on Compellent disk shelves, go for it! *

* OK, to be fair I can only personally vouch for the SC220 and my disks specifically. But I think it’s a safe bet that all Compellent stuff from that generation is basically the same.

I do have an important caveat: The drive sleds/trays for the SC220 look like they should fit in an MD1220 (or other generic-ish Dell hardware). They do not.

Both the SC220 and the MD1220 have tiny metal tabs on the bottom of each drive slot. Those tabs ride in the groove on the side of their respective sleds. The tabs and grooves are arranged in such a way that you cannot put Compellent drive trays in generic Dell hardware and you cannot put generic Dell trays in Compellent hardware.

That’s not a big deal if you get an SC220 full of disks. But if you get a non- or partially-populated unit, you’ll need to find Compellent trays even if you’re using whatever disks you happen to have laying around.

Either that, or you can try bending the chassis’ tabs out of the way. They’re just stamped into the metal, so presumably with enough leverage you could bend them down.

I should also note that I’ve heard bad things about using Compellent head units (drive controllers) in a home lab or small-budget environment. You’ll probably run into licensing issues, and of course you’ll have to support proprietary software and hardware yourself. Plus the controllers will only support Compellent drives, and will complain vociferously about generic drives. I’m only endorsing the use of the disk shelves and disks themselves.

The SC220 is on the top, with the connected DL580 at the bottom of the picture. In between are a number of disks, including a 36-bay SuperMicro chassis and a Dell DR4100 (which is just a fully loaded R720xd at a cheaper price).

I haven’t thought of this Muppet in a very long time (or perhaps ever), but Sam the Eagle looks like these drives.

Dell Compellent SAS drive trays look like Sam the American Eagle.

The HP Procurve 5406ZL and…

…a whole lot of other crap, vis a vis my opinions on used enterprise-grade networking hardware for the home (or small-ish business).

I purchased an HP Procurve 5406ZL on eBay mainly because I “need” 10GbE on my home network, which is almost recursive because it’s for editing 4K video, which I need for editing this video.

The bottom line for me is that you can’t beat the feature/price ratio when it comes to equipment like this. That is, if you can afford the resultant power bill.

It turns out that I have more battery chargers than sense, so I built this monstrosity.

Back in August I reviewed the Netgear 6100D from Sprint and followed up with a post detailing some advanced configuration options.

The Video

I also installed a flat panel 4G antenna from 4G Antenna Shop. I made a video detailing the unboxing and installation (which I just got around to editing together):

It’s my first video of this sort, so if you have any feedback please let me know in the YouTube comments or by email!

4G Antenna Shop

I didn’t get into it in the video, but overall I’d recommend 4G Antenna Shop. The cable and antenna I got were both of very high quality and definitely worth the price.

Their customer service was great; I had a couple of questions about my order, and one of their guys (Robert) got back to me within 15 minutes and was extremely helpful. They shipped really quickly, too.

I did have two minor issues, both of which I talk about in the video:

During checkout they give you the option of selecting your device so that they can provide the correct adapters to go from the cable (if you order it through them) to the device. At the time I’d ordered, they had an option for “Netgear Sprint Spark LTE”, which I thought was the Netgear 6100D. There was no separate option for the 6100D, but it turned out that they were referencing a different product, and so I received the wrong adapters. (They’ve since added the 6100D as an option.)

I chalked this up to being mostly my fault, as I didn’t know that there was another Netgear LTE device out there for Sprint Spark.

My other issue was with the packing job. Again, it’s a minor complaint because nothing was damaged, but the box arrived pretty beaten up with holes in the top from the antenna mount having poked through. There was no packing material to keep the box rigid, and the antenna and cable were just sorta rattling around inside.

Bear with Me…

Oh, and sorry if I rambled on a bit in the video. If you couldn’t tell from a lot of my other posts on here, I have an aversion to brevity. :)

I’m hoping to get some more how-to and instructional videos out there in 2015, so please subscribe to my YouTube channel!

(Hey, I’m allowed to shill for myself, right?)

For home or low-demand virtualization, you can’t beat the Dell R905 for price. Consider that, as of the time I’m writing this post, you can get an R905 like I did with 128 GB of RAM for about $960. That’s only a little more than the cost of the RAM!

That machine has 4x AMD Opteron 8356 quad-core CPUs @ 2.3Ghz and two built-in 10gbps ethernet ports (plus 2 gigabit ports), a PERC6i controller, dual PSUs, and a full enterprise DRAC. It’s a little old, but you can’t get those specs in any other machine in a nearby price range. (OK, the R900 and the HP DL580 are very similar in spec and sometimes comparably priced).

I chose an R905 in part because it only has 4 big 120mm fans (in redundant pairs). Larger and fewer fans generally makes for a quieter machine, and sometimes this enterprise hardware can get awfully loud. I was really lucky when I got it racked and found that it was indeed very quiet. Small office quiet, even under moderate load and in a 79F degree room. (I think the fans were spinning somewhere around 2000 RPM).

It all fell apart though when I added a PERC6/E to support an HP MSA70 DAS to supplement the R905’s measly 8 2.5″ hot-swap drive bays. For some reason the BMC (which monitors and controls the fans, amongst other things) decided that the PERC6/E was the last straw and started running the fans at 5175 RPM constantly. And that is most certainly not quiet.

After assessing my options, I decided to modify the fans. I didn’t have a solid plan, but I figured that some 555 timers, a few capacitors and resistors could change the tachometer signal coming out of the fan to trick the BMC into thinking that the fan was spinning faster than it actually was. Of course, I didn’t want to make these modifications on the only four fans I had on hand — the four that were actually keeping the system cool — so I decided to buy another four from eBay. They were only $40 all-in!

One eBay listing in particular caught my eye. It said “Buyer may receive a fan produced by one of 6 different manufacturers (see picture below). But, no matter who the manufacturer is, the fan is guaranteed!!” The manufacturers included Delta, NMB, Nidec, and JMC/Datech. And interestingly enough, from the pictures it looked like the different brands had different blade configurations.

Images borrowed from the auction page of red_planet_trading on eBay

My system originally came with Nidec UltraFlo fans which have 5 steeply canted blades, an airflow rating of 250CFM and a max power draw of 6 Amps. The Delta PFC1212DE fans which I’d ordered had 7 blades with a more shallow cant, an airflow rating of 205CFM and a max power draw of 4.8 Amps:

The Delta fan I ordered. Picture is from the auction listing by steals_an_deals. They shipped quickly and the order went smoothly.

From the specifications (particularly the lower power draw), I surmised that the Delta fans might spin more slowly than the Nidecs to move the same amount of air. On the other hand, the lower CFM rating on the Deltas might mean that they would need to spin faster to keep up with the airflow of the Nidecs. I held off on ordering 555 timers until I could try out the new fans.

Happily, the Deltas are significantly quieter! When the server’s cover is taken off, the fans spool up to maximum RPM. As I hot-swapped each Nidec for a Delta, I could hear the sound decreasing. After putting the cover back on, the fans gradually throttled down and I monitored their speed through Dell OpenManage. When the Deltas hit ~5175 RPM (the speed at which the Nidecs had been running), they were significantly quieter. They eventually leveled off around 4500 RPM and a very tolerable volume (though not as low as prior to adding the PERC6/E).

The moral of the story is this: There are probably many OEM-approved fans out there for your server. Look into their specifications (many times the mfr. will publish sound levels at varying RPMs), and find the most “silent” ones. It’s not always worth it to risk messing up your cooling and burning out your system with custom mods!

Update: Another interesting note from all of this is that the fans made for Dell have 5 wires, whereas on the spec sheets for the generic version of the same fans they only have four wires. The four wires are for power, PWM control, tachometer, and ground. I don’t know why the Dells have the fifth. My guess is that it’s a sense lead so the BMC can identify the fan from amongst the different brands and models. If anyone knows the real answer, please leave a comment!

Background

I recently purchased a Dell BMX blade chassis on eBay that came loaded with ten 2x dual-core, 24GB PE1955 blades.   For a system with 40 cores, 240 GB of RAM and two 16-port gigabit switches in a 7U frame, $2500 was too good to pass up.  Especially since shipping cost me a mere 2 hour round-trip to Brooklyn.

I didn’t really need ten more servers, so I figured I’d sell off 5 or 6 of them (hopefully breaking even on the entire system — the 4GB FB-DIMMs in 6 of the servers is worth $1450 – $1900 alone).  The remaining servers would be all mine!

But I forgot to research the noise!  The chassis screams like a jet engine when powering up.  Even after it settles down to “idle”, with a couple of blades powered up the thing is still as loud as a decent-sized vacuum cleaner!

Research

I searched high and low for solutions to the fan noise.  Not a single search result discussed quieting this system for home use.   The only advice I could find was “don’t buy one”.  Heh.

I didn’t want to swap out fans with slower ones like this guy or this guy did on PowerEdge rack servers.   I don’t mind a little soldering, but there are two problems with that approach when dealing with the blade system:

1. There are 16 fans in the chassis (3 in each of the 4 PSUs, and 2 in each of the 2 fan modules).  That’s a lot of soldering, a lot of fans to buy, and a lot of things to potentially screw up.
2. More importantly, I’m concerned that quieter, slower RPM fans wouldn’t move enough air through the chassis during peak utilization and peak ambient temperatures.  I don’t want to find out the hard way when 5 of my production servers start shutting themselves down during the summer months.

My solution was to hack the DRAC/MC firmware.  The DRAC monitors fan speed and temperature, and I assumed it controlled the fans based upon various sensor readings.  I wanted to change the parameters for fan operation, for example by allowing the fans to run at minimal levels through a broader temperature range.

In fumphering around with a hex editor, looking for any reference to “fan” (hey, you gotta start somewhere), I found this:

So there was a way to control fan speed through the DRAC, without having to modify the firmware!  What I found seemed to be the text for a menu, but of course no such menu is exposed.  (I checked via serial, telnet, and web interface to no avail).

A little more searching, and I found this nugget:

Amongst the text for the “?” (or “help”) command in the DRAC/MC CLI, there was a command I’d never seen before in the help text itself, nor anywhere on Google:  fanctrl.[0, 1, 2 3]

Undocumented Commands

In addition to the fanctrl command, there are quite a few others that don’t appear in the normal help text.  I’ve listed the more intriguing ones below, along with my best guess as to their usage. There are a lot of detailed config commands that you can view in a slightly cleaned up version of the relevant raw data.

Don’t want to/can’t use the console for some reason?  Just go to http://[DRAC IP]/debug_command.htm after logging in and you can execute any command from there and see the output.

Conclusion

My goal was to reduce fan speed  in order to make the Dell blade system usable in my open basement.  Sadly, even with the most throttled of speed that fanctrl has to offer, it’s still too loud for my (and more importantly the wife’s) taste.  The entire system is going up for sale on eBay, minus the chassis.  It’s too expensive to ship it via regular carrier, and lets just say that I have a Visio layout for a basement data room lying around.

If you have a dedicated server room or closet, a Dell 1855/1955 blade system may be the right choice for you for home use so long as you tweak the fanctrl settings and don’t let the system heat up too much.

To the best of my ears’ reckoning, an “untweaked” chassis with 5 powered-on blades makes noise equivalent to a leaf blower with some fans running as low as ~5000 RPM and others at ~10,000 RPM.  On setting “0” (ultra-low, if I’m correct) it’s just a little bit louder than my 10 year-old dryer with some fans at ~2500 RPM and the fastest ones at ~7500 RPM.

If you are going to replace fans, the small ones at the front of the PSUs are generally the fastest, smallest, and loudest.  Unfortunately, there are still 8 of them.  And if any one of them falls below RPM threshold, all the other fans will speed up to compensate.

The server rack (well, shelving unit) isn’t pretty, but it gets the job done.  I’m not exactly the computer version of Scrooge McDuck over here, so I stick with desktops.  The UPS on the right is a real old beater — I’ve replaced the batteries 3 times so far.  It’s a nice double-conversion full sine wave model, so I keep it around.

My workstation setup.  My primary machine needs upgrading badly:  A Dell GX280, P4 3.0Ghz, 3GB RAM.  It works for now.  All the monitors are hooked up to something or other, but I didn’t have them on when the pic was taken.  Yeah, it’s a mess.  That will never change.

I’ll put up some more illustrative pictures eventually, but the idea is that the cord on the left provides power to a couple of receptacles in my media cabinet upstairs.  My HTPC, cable boxes, and some other electronics are connected to that receptacle.

The cord on the right (I guess you can tell from the labeling) goes to a receptacle on the wall behind my TV.

The idea is that I’m going to put a UPS (or two) inline with those two connections so that they’re out of the way but still protect my media equipment.