Reetman: The Worklog

Road-Kill

mf came to me after I had done a previous casemod for him (Project Salvage). He came with the question whether I could come up with a design that could hold 12 hard drives (yes, you read it right: 12), so we stuck our heads together to come up with a viable design that would work. It only had 3 major specifications it had to comply with.

- It had to look sleek. As sleek as possible with minimal design features on the outside
- It had to be black and basically have the shape of a black box
- It had to be able to cool the hard drives sufficiently that they wouldn't fry

With these ideas in mind we first came up with a design that we had begun building, where everything was fixed with pop rivets. This turned out to be my worst mistake as it compromised the look of the case, and at the same time we came to the conclusion that we had a completely wrong idea about the cooling.

So we started on the second build and this time most of the frame work would be glued instead of pop riveted. This turned out to be in our minds the best solution to maintain the look but still have enough strength to the case. This was our design point:


[ the final design wireframe ]

4x 120 mm fans would provide an airflow strong enough to cool it all, and the mainboard and PSU positioning would mean that the bottom of the case would provide all the air needed. The case is made mostly out of 15mm aluminium angled strips. In the picture below you can see the first load that would make up the basic frame. What I did to make the frame as sleek as I could was to build two frames (a top and bottom frame) and connect those with aluminium strips as you will see later on. The frames were made by cutting the strips at an angle of 45° to make an almost perfect 90° angle (I say almost because nobody's perfect, and if you are, then I wish you much joy in your private little world), and glue them together with a two-component metal glue that ensured great strength (about 180kg of force per square cm). As you can see I used a third strip to connect them and also provide a connection point to connect both frames. I first made 4 pieces of 90° angled strips, and glued two of them together at a time using a wooden mould.


[ aluminium strips made into frame corners ]

Eventually I had both frames done, two identical frames and four strips laying next to it which would become the upright supports. I took the bottom frame and glued the supports onto them and let them dry. After having glued the supports and let them dry I took the top frame and positioned it on the bottom frame and the supports. The end result was a basic frame made strong enough to take my weight at that time; I was a little over 125kg, so yeah, it's strong.


[ just don't mind the booze in the left corner there,
no booze was hurt injured killed or consumed during this build ]

When the basic frame was done it was time to make the the inner frameworks to hold the mounting of two towers consisting of 6 HDDs each and all the other gear. First I placed a pre-drilled plate on the bottom, a plate that will let enough airflow through for the cooling of the HDDs. After that I began on making a frame that would support the I/O and the two HDD towers. To do that I first placed four upright supports. As you can see the bottom plate doesnft make it all the way. This was done intentionally because the opening is for the I/O connections. Next, to be able to mount anything on there I had to put in two horizontal supports. Now with the horizontal supports in place I had a place to fix the HDD towers and the I/O panel too. With that done I went along and made the supports for the PSU. These supports were made in the most basic of methods by grabbing an old PSU, since PSUs have a standard measurement by the ATX standard.


[ frame with air intake mesh and frame with psu mount]

The second PSU is there just for the extra weight and to make sure the contact is good enough between the two glued surfaces. We first had the idea of placing the system HDD which would be a 2.5" notebook HDD next to the PSU, but when the idea of using a port multiplier came up (read mf's side how that went) that space was reserved for the PM and the HDD. So I had to build in two supports for those as well.
Next stop was making sure the PSU could be mounted. I had made the supports for it but this alone wouldnft hold the thing in place, or so I thought... I had done my job a little too good, and the PSU stayed in place even without any additional fixing. This allowed me to make sure the mounting would be just right in height giving enough clearance below for the power cable and above for the various molex connectors and others. Since most PSUs come with a small angled piece to allow a different mounting I dicided to use that instead of its normal ATX standard mounting.


[ psu clearance check and crossbrace mount ]

As you can see in the picture above a little crossbrace was made by gluing two strips of 15mm aluminium together so one would fit between the supports and one over it. The one that went over was glued to the supports. The inner one leveled things off nicely so that the PSU could be fixed properly, by the way donft pay any attention to the sowing machine, I was doing this in my own home and my mom used the room as well.

Okay, so at this point in the story we take a break. Why you may ask? Very simple... My trusty old imitation dremel was getting a bit worn out, made a lot of noise and had a rather nasty rattle to it. I could do either of two things: buy a new one, the same as I had before, or invest some more money and buy me an original Dremel® and have a bit more options for future casebuilds or casemods. After much long thinking, I opted for the latter. I bought me a real dremel and with it a tungsten carbide mill which is used for milling light metals such as aluminium, which just so happens to be the material Reetman's entirely made out of!



After the break I got cracking on the rest of the case. At this point I had a few major details to tackle; I still had the HDD-mount, I/O top panel, HDD towers, mainboard backplate hinge and the I/O panel itself to make and lest not forget the mounts for the wheels.
As you can see below I decided to make the system HDD mount out of 4 lengths of angled aluminium strips and a simple plate of 1,5 mm aluminum. First gluing two strips to the frame and two strips to the plate so I had some room to make mounting a HDD easy and yet funky. Because I chose to make it in such a way that de HDD just slots in it is screwed tight on one end and that will fix it in place. Next is the I/O top plate. This is so basic it's funny, although due to the rather quickly changing small design features it was an afterthought to use one at all, so it was rather a pain in the neck to fit it inside the existing frame, but see below on what came out. A simple 292mm by 149mm plate of aluminium and wefre done.


[ system hdd parts and i/o top panel ]

 
mf


It was in the Forest of Dean where I came up with the idea for Reetman. I had decided that all my flat storage was starting to pose a risk, as I was nearing the 1TB border in disk space, and I was going to need protection for my important files. At the time I had sort of a guerilla-style disk layout, one 120GB Western Digital, two 160GB Western Digitals, a 200GB Seagate, a 250GB Seagate, and a USB 2.0 80GB Maxtor which I'd gotten from Road-Kill after I told him how frequently Maxtors died.

Ironically, earlier this year the Maxtor died, while all my WDs and Seagates are still going strong, putting my personal record for dying Maxtors at 2, with friends around me having countless problems with them.
Anyway, all of these disks were PATA, and some even connected with plain old IDE cables instead of UATA133 cables. I'd learned from the 10 years of computer use before then, that partitioning drives is useless, so all my drives had one big partition, aptly named "Dump N", with N being the disk number in chronological order. For the record, I never went past Dump 5, after that I started building Reetman and the disks I was going to use later I called "Rectum N".

At first, I just wanted to upgrade my current box (Zoef, case Project Salvage) with RAID-5 volumes, as I already had two 160GB drives and I'd just need to buy another 160GB Western Digital and I'd have a 320GB RAID-5 volume. I was also thinking about getting two new 200GB Seagates and fitting them into a second RAID-5 array. At the time I was thinking about getting software RAID and perhaps tying together the RAID-5 volumes in JBOD, as I hate partitioning, even with logical volumes. The same evening, after a bit of a chat about it with my dad, we concluded that I'd need too many PATA add-on controllers to fit all these disks, and that it was never going to fit inside Salvage.
Okay, so I came up with a software RAID dedicated file server box. I wanted to cut costs as much as possible, and I'd just keep the OS setup as plain as possible leaving enough CPU free for XOR calculations. Of course you are laughing now, software RAID performs piss-poor, in Linux you don't even have any data security (Tronic, a friend of mine has had multiple crashes with Linux software RAID-5), and it's basically a big joke for people that want the illusion of data safety with minimal expenses.

the first scribbles
[ the first scribbles ]


So with the physical size problem solved by moving the RAID arrays to Reetman, I was still thinking in tight budgets and thinking about how I'd want to have Reetman be a mix of PATA and SATA, having multiple arrays tied together with JBOD. This is about where the idea ended that evening, and when I got back from holidays I presented it to Road-Kill as a case project.
It might be interesting to note where the name "Reetman" comes from, as Road-Kill and I basically met eachother at Rock Werchter, a rock festival in Belgium in 2002. The organiser of the festival; HUMO, has a mascot named Reetman. It's a dude with a gigantic butthole. All the Werchter booklets and things had this cartoon character on them, and I instantly fell in love with this repulsive, disgusting little guy. When I was thinking up this whole dedicated RAID-5 box idea, I came up with the Dutch phonetic pun of "reet" and "raid" (both being almost identical in pronunciation). Some people that haven't seen the name in writing even assume that the name is spelled "RAIDman", instead of "Reetman", but oh how wrong they are. :)

humo reetman comic
[ hey coco ]
[ reetman... ]
[ uuh... i think a parrot just crawled up your ass... ]
[ he pays rent ]

With the theme decided upon and the basic idea present, we were ready to do some designing. We went through a few different layouts before rethinking the hardware setup again. As I was actively researching RAID and anything concerning storage, I learned about the impracticalities of software RAID along with a bunch of other info. Now here came a slightly bold move, I threw the tight budget out of the window, and set some basic rules.

- Reetman will have one RAID array, not multiple tied together
- We'll be using a hardware RAID card
- I want a nice round number for total disk space, like 3TB
- I'm not calculating what it's going to cost, I buy things as we go and I'll tally the total price afterwards
- It's going to be headless, simple and jaw-dropping

With all this in mind, Road-Kill and I spent countless hours brainstorming the ideal internal layout and external dimensions. We started out with a small cube, and expanded where extra room was necessary. You can read how all that went in Road-Kill's log on the left.

My story continues in the end of 2006, when we resumed construction after a long break. Originally I had intended to go for 12x 300GB drives, but halfway in 2006 I had to move to 320GB disks, because the 300GB models were end-of-life and could not be ordered anymore. I sold off most of the 300GB disks and kept one as a data drive for my workstation. There were two advantages to the move: the 320GB models are the first to feature perpendicular recording, a technique that increases data density and thus seek time, speed and capacity.

The case was starting to take shape, the preliminary deadline grew nearer, and I would have to start ordering parts. I did a lot of research, and came up with this spec sheet:

Motherboard: MSI 945GT Speedster-A4R
Processor: Intel Celeron-M 430 (1.73GHz)
RAID Controller: Promise SuperTrak EX8350 with Addonics AD5SAPM-E Port Multiplier
Memory: 256MB DDR2
Power supply: FSP400-GNF 400w Fanless PSU

The motherboard was pretty much perfect, it features a 16x PCI-Express slot for the RAID card, onboard VGA (with DVI as a nice gimmick), and dual gigabit ethernet from two separate Intel Pro/1000 chips (so no cheap chipset-integrated IRQ-hungry solution). The RAID card is 8-port, and the Marvell chips it has on board support port multipliers, so I planned a 1x5 port multiplier to go with it. The math for this is as follows:
7 ports + (1 port x 5) == 12 ports

The preliminary deadline was set for April 20th 2007, because there was a big LAN party that date; The-Party 5. Attendees: 1000. There was a separate server area with a gigabit backbone for lots of filesharing fun. I also wanted to show off my case at the CaseJunkies stand. This was starting to pose a problem:
I ordered the motherboard from my favourite computer shop in town, Trendtek Computers. When it arrived (in time), it was DOA. So we RMA'ed it. And waited for it to get sent back. And waited some more. It was already begin April, and I needed to get software configuration over with. Thankfully Yee-Ping, the shop owner, lent me a replacement motherboard with CPU (because they didn't have any mobile socket Intel boards). She really is the best.


[ the motherboard ]


During my storage research adventures, I read a lot about Serial Attached SCSI. It's basically SATA's big brother, meant for enterprise storage solutions. Now there are a couple of things they improved on when thinking up SAS, and one of them caught my attention. With SAS, there aren't two separate connectors for power and data, but they're both in one wide connector. If you've ever worked with SATA in tight cases, you might know how those little #$%@ data cables will partially or completely come loose if you do so much as sneeze at them, while the SATA power cables have none such issues because they're wider. There are solutions for that (lockable cables), but the thought of pulling out and connecting both power and data in one motion, not to mention the added tidiness in cable management, was very interesting. At first, I was simply looking for SAS cables. These are backwards-compatible with SATA, so you can use them with SATA disks and SATA controllers (note that you can't use SATA cables with SAS disks, or use SAS disks with SATA controllers; the compatibility is one-way only). When I found a company that made these cables, I also found they made the same type of wide connectors with power and data on one plug, for SATA! So I went to Trendtek and explained my need for goods. They gave me a huge warehouse catalog (from Javocom), and after extensive page flipping I found that they sold these very SATA "combi-cables". I immediately ordered 14 pieces, which arrived in a timely manner. Note that even though the connectors aren't lockable, you can hold the entire weight of a hard disk only by the friction of the connector. Sweet! (Yes, that is a brand new SATA 320GB disk hanging in mid air :D)


[ sata cables ]

Next, I ordered the RAID card and PM from WebConneXXion, a webshop which specialises in storage solutions. John, the shop owner, put a helpful question in the comment box that came with the order confirmation, asking if I was intending to use the PM with the SuperTrak. Yes I was! Now it seems that even though the Marvell chips support PMs, Promise didn't bother to support it at the firmware level, and even though their spec sheet says it does! Bad, bad Promise. I was eternally grateful that John warned me about this, and I asked what else I should do. He gave me a few offers, but I had only one PCI-E x16 slot, and I would definitely need one card to drive all the disks. In the end he offered me the Areca ARC-1230, which is a PCI-E x8 card with 12 ports, 256MB upgradeable SO-DIMM memory, and its own NIC for the webinterface! Whoah, way too much luxury. But it was the only choice, and damn it was a good one.

[ areca raid card ]

The RAID card deserves its own bit of story. This thing is absolutely awesome. It comes with 12 lockable SATA cables (which I didn't need as I had 14 combi cables), a very thick and exhaustive manual (which explains literally everything from powering on to using the webinterface), a driver CD (which I didn't need because Areca submitted the Linux driver source code to kernel.org, and it now ships with vanilla editions of the kernel from version 2.6.20.7 onwards), and... A passive heatsink for servers with enough airflow! Areca, I love you. I immediately removed the slot bracket and installed the passive heatsink, shown on the picture above.

[ cool logo :D ]

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