Dell PowerEdge T105
Today I received a Dell PowerEDGE T105 for use by a client. My client had some servers for development and testing hosted in a server room at significant expense. They also needed an offsite backup of critical data. So I suggested that they buy a cheap server-class machine, put it on a fast ADSL connection at their home, and use Xen DomU’s on that for development, testing, and backup. My client liked the concept but didn’t like the idea of having a server in his home.
So I’m going to run the server from my home. I selected a Dell PowerEDGE tower system because it’s the cheapest server-class machine that can be purchased new. I have a slight preference for HP hardware but HP gear is probably more expensive and they are not a customer focussed company (they couldn’t even give me a price).
So exactly a week after placing my order I received my shiny new Dell system, and it didn’t work. I booted a CentOS CD and ran “memtest” and the machine performed a hard reset. When it booted again it informed me that the event log had a message, and the message was “Uncorrectable ECC Error” with extra data of “DIMM 2,2“. While it sucks quite badly to receive a new machine that doesn’t work, that’s about the best result you can hope for when you have a serious error on the motherboard or the RAM. A machine without ECC memory would probably just randomly crash every so often and maybe lose data (see my previous post on the relative merits of ECC RAM and RAID [1]).
So I phoned up Dell (it’s a pity that their “Packing Slip” was a low quality photocopy which didn’t allow me to read their phone number and that the shipping box also didn’t include the number so I had to look them up on the web) to get technical support. Once we had established that by removing the DIMMs and reinserting them I had proved that there was a hardware fault they agreed to send out a technician with a replacement motherboard and RAM.
I’m now glad that I bought the RAM from Dell. Dell’s business model seems to revolve around low base prices for hardware and then extremely high prices for extras, for example Dell sells 1TB SATA disks for $818.40 while MSY [1] has them for $215 or $233 depending on brand.
When I get the machine working I will buy two 1TB disks from MSY (or another company with similar prices). Not only does that save some money but it also means that I can get different brands of disk. I believe that having different brands of hard disk in a RAID-1 array will decrease the probability of having them both fail at the same time.
One interesting thing about the PowerEdge T105 is that Dell will only sell two disks for it, but it has four SATA connectors on the motherboard, one is used for a SATA DVD player so it would be easy to support three disks. Four disks could be installed if a PCIe SATA controller was used (one in the space for a FDD and another in the space for a second CD/DVD drive), and if you were prepared to go without a CD/DVD drive then five internal disks could probably work. But without any special hardware the space for a second CD/DVD drive is just begging to be used for a third hard disk, most servers only use the primary CD/DVD drive for installing the OS and I expect that the demand for two CD/DVD drives in a server is extremely low. Personally I would prefer it if servers shipped with external USB DVD drives for installing the OS. Then when I install a server room I could leave one or two drives there in case a system recovery is needed and use the rest for desktop machines.
One thing that they seem to have messed up is the lack of a filter for the air intake fan at the front of the case. The Opteron CPU has a fan that’s about 11cm wide which sucks in air from the front of the machine, in front of that fan there is a 4cm gap which would nicely fit a little sponge filter. Either they messed up the design or somehow my air filter got lost in transit.
Incidentally if you want to buy from Dell in Australia then you need to configure your OS to not use ECN (Explicit Congestion Notification [2] as the Dell web servers used for sales rejects all connections from hosts with ECN enabled. It’s interesting that the web servers used for providing promotional information work fine with ECN and it’s only if you want to buy that it bites you.
But in spite of these issues, I am still happy with Dell overall. Their machine was DOA, that happens sometimes and the next day service is good (NB I didn’t pay extra for better service). I expect that they will fix it tomorrow and I’ll buy more of their gear in future.
Update: I forgot to mention that Dell shipped the machine with two power cables. While two power cables is a good thing for the more expensive servers that have redundant PSUs, for a machine with only one PSU it’s a bit of a waste. For some time I’ve been collecting computer power cables faster than I’ve been using them (due to machines dying and due to clients who want machines but already have spare power cables). So I’ve started giving them away at meetings of my local LUG. At the last meeting I gave away a bag of power cables and I plan to keep taking cables to the meetings until people stop accepting them.
As a matter of fact I find some problems with the cheap T105, which I also bought.
- The first one is the outrageous price they charge for the extra RAM - I ended up buying it myself for around a *third* of the price, with lifetime warranty.
- Also I find the machine quite noisy, with some low-level “hum” very annoying, which I’d bet on the two harddrives I installed, as the toolless system they use seems to not damper at all the drives vibration.
- If you want to install a fan in front of the drive cage (you know, a 24/7 server with two drives that close…), a standard 7cm fan is not compatible with the 5 pin connector dell uses.
- (this is not Dell’s fault, but…) the network card is not supported on opensolaris, which I intended to use for this machine.
- PCI is 3.3v, not 5v, so no network card I had worked on the machine. Also, the system used for fixing the cards sucks, plainly, though I don’t expect to use it too much so that’s pretty much just a nuisance.
And a tip: if you want to install a third hard drive, it fits perfectly on the floppy cage under the second CD drive without any adapter ;).
June 26th, 2008 at 8:01 pmJisakiel: Yes, the prices for all their parts are quite high. My client is paying more than $700 as the price difference between the base configuration of 512M and the desired configuration of 4G in 2*2G modules. I expect that I could get RAM cheaper somewhere else, however most computer stores don’t sell ECC RAM and the one place that did sell it didn’t return my call when I asked for a quote. But when things don’t work (as in this case) buying it all from Dell is an advantage.
While I haven’t got it working properly yet, the one I have hasn’t made much noise in my brief tests.
June 26th, 2008 at 8:56 pmI’ll vouch for Dell, their hardware is decent and the support is great. However, they do suck at packaging, especially with regard to power cables. We purchased an APC rackmount UPS from Dell as part of a larger order, and the day after the UPS arrived, a large box containing only the 20A power cord arrived, along with 2 smaller boxes which each contained 5x UK/Malaysia style wall-to-PC IEC power cords, instead of 2 boxes containing 5x pass-through IEC power cords (for plugging devices in to the UPS).
Also, I’m not sure what the exact difference in price between the T105 and SC440 is, but the SC440 might be a plausible alternative for those who want a slightly less cheap basic server system, which has ECC memory, SAS, fits in a rack perfectly on its side, etc.
June 26th, 2008 at 9:58 pmRegarding storage, you might find this paper relevant:
“An Analysis of Data Corruption in the Storage Stack”
Lakshmi N. Bairavasundaram, Garth Goodson, Bianca Schroeder, Andrea C.
Arpaci-Dusseau, Remzi H. Arpaci-Dusseau
FAST ‘08
http://www.usenix.org/event/fast08/tech/full_papers/bairavasundaram/bairavasundaram.pdf
June 27th, 2008 at 12:21 amhi,
I never used DELL hardware, but many people tolds me about problem they meet. I t seem that is not your case.
July 3rd, 2008 at 7:52 amPersonally i vote for the PRIMERGY TX150 S5 . More expensive but a very secure server for little businness
Give me your opinion
dodgers: From the specs that Fujitsu looks like a nice box. Hot-swap hard disks, support for four disks, hot-swap PSUs, and all the usual server features. As you note it’s more expensive, but if you need those features then it’s probably good value. The Dell T105 is a cheap server designed for situations where you don’t mind taking the machine apart to change a broken disk. A broken PSU would probably take about 24 hours to get fixed with my Dell, not a big deal for what I’m doing.
Neal: Interesting paper. I can’t wait for filesystems with similar technology for detecting and correcting such errors to be available in Linux!
July 4th, 2008 at 9:39 am[...] Comments etbe on Dell PowerEdge T105john howell on Rip It Off unless you use windows?dodgers on Dell PowerEdge T105Don Marti on The [...]
July 4th, 2008 at 9:41 amI purchased two of the T105 units. One for a doctor’s office and one for his home.
I can attest to the vibration issue. It is definitely the high RPM disks (two in each server) which are not dampened at all. The whole server acts as a sound board especially with the side cover on.
We did find a little dampening by putting the server atop a book that allowed th legs to dangle. Having the bottom of the server supported solely by the yellow pages seemed to help. The final solution was to actually leave the side-cover off of the unit and to pull the drives a little out of their bays. Of course I hope no one bumps the server.
It would be nice if Dell came up with a new mounting rail or something (perhaps with rubber in it) that might dampen some of the vibration. These high RPM hard drives give off a lot of vibration.
Nice server though. :)
September 9th, 2008 at 6:53 amFrank: I guess it’s just an engineering trade-off that we (as customers) have to deal with. High speed disks vibrate, the way to damp this is by having a heavier case and rubber mounts - both of which cost more and increase the size of the unit. I was after a system that’s not overly large and was reasonably cheap (criteria the Dell T105 matches reasonably well), being a little noisier than I might prefer is a trade-off.
But as I installed two relatively cheap 7200rpm disks I didn’t have a problem. The T105 was quieter than the previous machine it replaced and the one before that (which were both “desktop” class machines).
September 9th, 2008 at 11:49 amI notice that the rails being used are blue and don’t seem to have any rubber between the drives and the rails the way they do in the Optiplex worstations for example.
I’m going to look into whether or not the Optiplex rails will work in place of the stock T105 rails. If it works it’d be great because they’re cheap and plentiful.
I’m also going to call Dell today to see if they have a newer updated rail available for mounting 3.5″ drives.
Yes it’s a trade-off but in this case money wasn’t really as important as quality. This is a doctor’s office and anything that takes focus away from the patient is not good.
I’m definitely not complaining about the server - it’s very nice. After I fix this vibration it will be /perfect/
September 10th, 2008 at 11:17 pmI have two DELL SC440 servers and they are excellent for the price. Far cheaper than I could find on even discount sites. I have to agree that the price of optional components is crazy (£200 for a 750GB SATA drive!)
so best get those somewhere else.
haven’t run into the vibration issue but then I only have one drive in each server.
I am thinking of getting a T105 now (purely on price basis) and will need to pop three disks in here..I am replacing a very slow file/print/DNS cache/time server in the office with this new machine.
I will need to pop the two SATA RAID1 drives into this new machine. How easy will that be? Can you buy these drive cages that DELL uses?
September 25th, 2008 at 8:01 am