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Silent, Durable Media For Servers?
Aldurn asks: "Recently, I've come into a living situation where having my rather loud computer continuously running is distinctly suboptimal. In order to maintain my current email address and webserver, in addition to running a decent set of iptables rules for the house, I decided to buy a Mini-ITX-based server. Currently, /dev/hda is running on a CompactFlash card, but I realize that this probably isn't the best thing to do when running a mail server, due to limitations of the media with regards to the number of writes possible over the lifetime of the media. I'm looking to add another storage medium to the device for /var in order to maintain the logs, as well as for mail storage and other bits that like to live in that directory. The media doesn't have to be terribly large (preferably at least 64 MB), and can be connected through IDE, USB, the floppy connector, or through the network. The end goal of this exercise is simply to prevent my poor CF card from dying an early death from continuous writes. What do you suggest for such a situation?"
Just use a ramdisk, and a UPS (if you even need it). For reference, I use a flash-disk based Mini-ITX board with a UPS based on two standard 6V lantern batteries -- lasts about 8 hours.
I've had this sig for three days.
Why not just stick a hard disk in it and work on soundproofing. I've got a similar setup and run it on a PII 400 (passively cooled) with a Maxtor 40Gb 5400rpm drive in it. Its almost completely silent when there is no disk activity and with all my heavy disk activity cron jobs scheduled for when I'm at work, rather than the early am, I barely even notice that there's a box in the room. If its still too noisy, you could investigate soundproofing the case some more.
Of course you could always just do the Ramdisk thing that the guy above suggests. I contemplated this, but the cost of getting a UPS up and running on it was more than living with the small amount of noise.
Seagate has some amazingly quiet drives based on fluid bearings, I'm assuming that this fairly obvious choice has already occured to you and was deemed unsuitable for some reason.
Barring a regular hard drive, the first and most obvious method is a solid-state disk that's designed for continuous use. They're not cheap, but they're totally silent and quite fast, too.
As was already suggested, a RAM disk that periodically backs itself up to CF would work too. RAM is cheap! If you don't need all that CPU power, consider underclocking your setup to reduce the memory's heat generation, and therefore your fan's duty cycle.
You could try a magneto-optical disk. Some of the old 230MB 3.5" MO drives are nearly silent, and the media's rated for millions of writes and decades in storage. I don't know how noisy the 5.25" versions are, but they should be pretty quiet too, mostly owing to low spin speeds and finely machined parts. Again they'd be better as backing stores for a large RAM disk, due to limited i/o speeds and seek times. Being removable, backups are a piece of cake too.
Laptop hard drives are also pretty quiet, because their spindle RPMs are lower than desktop drives (5400 as opposed to 7200 or 10,000). Their platters are also smaller, meaning that the airspeed of the edge of the platter is much lower, creating less turbulence. Being physically smaller also means that you can mount it in rubber vibration isolators, preventing the computer's case from acting as a sounding board for spindle noise and seek clatter.
Also, check hard drive makers' websites for quiet seek modes. The drive's firmware can choose to drive the head servo in a noisy "performance" mode, or to smooth out the edges of the seek motions in a "quiet" mode. It results in a modest performance drop but a distinct reduction in noise.
Next step: Throw the entire computer into an acoustic printer enclosure. Back when impact dot matrix printers were the norm (and they still are in businesses that use multipart forms), everyone hated the racket they made. Elaborate printer cages were built, lined with acoustic foam and equipped with quiet fans to keep the occupant cool. This will drop a few decibels off any obnoxious machine, and they're designed to be easily opened for paper feeding, ribbon changing, etc. The only downside is bulk.
You can also throw bits of acoustoabsorbent foam into the computer's case wherever you find room. I live a few miles from a foam supplier so I picked up a few scraps. Rubber cement or spray-on adhesive work well. Any car stereo shop can sell you little bits of Dynamat, with a self-adhesive backing. An ITX case won't afford much space, but every little bit helps to cut down on panel vibrations and reflected noise.
Good luck!
Because you presumably don't want your email to be stored in just one place, I'd suggest a quiet (?), cheap RAID setup like this one
You might especially look in to this variation... ;)
four nine eighteen twenty-7 thirty-nine forty-7 fiftyeight sixty-nine seventy-9 eighty-8 one-hundred-and-nine one-twenty
Try using the JFFS2 filesystem. This is a Linux filesystem designed for flash media - it is aware of the media's limitations and try to get the maximum life possible. Flash cards are pretty cheap, and might be your best option if you want total silence.
Another option would be to use a laptop hard drive (with a laptop IDE to standard IDE convertor), an IBM microdrive, or even a standard IDE drive with good acoustic specs (some are designed to be quiet).
Is there a reason that your mail and web server needs to be located in the part of your home that needs to be quiet? Or even in your home at all?
For the ultimate in quiet, move the server elsewhere. If you don't mind spending the money, use a colocation provider like digitalforest. Or come to some sort of agreement with your employer and stick it in your office. I understand that it's cool to run your own server and all, but at this point mail and web stuff is pretty well understood by most ISP's... couldn't you maintain these services on someone else's machine located in a secure facility protected by all manner of UPS's, etc.? Keep the mini-ITX running on the CF card at home if you like for the ip tables.
If you really need to keep this server at home, try moving it down into the basement, or up into the attic, or sticking it in some sort of locked, weatherproof enclosure attached to the side of your house. (You might run the machine faster on cold days to keep the temperature inside the inclosure within the disk's operational temperature range!)
If you've got plenty of bandwidth and/or speed isn't a major requirement, get some space on a WebDAV server and put your /var directory there. You get the convenience of keeping your machine at home, and the reliability of having your mail and web stuff written to disk. As long as your connection stays up, you're fine. And without a connection, web and mail servers aren't all that useful anyway.
As long as it's a real cf disk and not a cf card on an ide adapter card, then the disk control does it's own wear levelling and you can expect a long lifetime... unless, of course, you're running a crazy mail load. But it doesn't seem like it if 64MB is sufficient.
Wouldn't a usb key do what you want(they're about the size of compact flash, if not larger, and don't have the limited write problem, to my knowledge)
I have an old laptop as a small mail server in my network (100 MHz Pentium, 16 MB RAM, 800 MB disk). All the APM settings are at max except that the machine will never be turned off. The hard drive turns off after a few minutes of no action and because the CPU load is almost nothing, the fan is practicly never on. When the server is idle, it doesn't make any sound al all!
I recently solved this problem myself. I had a mail server running in an ATX case which was getting on my last nerve. I got an Antec Mini-ATX case from BestBuy ($70), so now I could put the thing almost anywhere. Location definitely makes a difference, for I was able to place the thing in a little nook by my bathroom. Heat problems, you ask? Nope. Got a Via C3 700 MHz motherboard combo from Pricewatch for around $75, and it idles at 30 degrees, and this is without the case fans I haven't gotten around to installing. Also, the air coming from the power supply in the case is not even warm, and the power supply is quiet. The only problem is the CPU fan is still loud, but the location of the computer now makes it mostly a non issue. I may still replace the CPU fan in the future so I can hear dead silence when walking by the computer. I also use one of my Seagate Barracuda IV drives. This drive does not whine like the Maxtors-- it is competely silent when idle. You can hear it during writes, but the quality of the noise isn't bad like I've heard in Western Digital drives, or those loud crunching Dell desktop drives which drive me mad.
I hear that the Via C3 1000MHz CPUs can run fine without a fan, and you can get one of these with a motherboard for less than $200. I opted for the cheaper route, though. Anyway, you HAVE to get a quite hard drive, because once you silence the other components, you'll be surprised by how much noise the drive makes, and it'll definitely hurt the quality of your sleep.
I just set up a soekris system (http://www.soekris.com/) with an IBM microdrive. That sucker is whisper-quite, just the occasional clicky-clicky from the drive.
/var mounted on a 10MB ramdisk (this is with FreeBSD by the way) and it is flushed to/loaded from the drive at shutdown/boot .. so the drive activity is minimized.
I have no idea about the lifespan of the microdrive when used in a server but I guess I'm gonna find out!! I do have
There are also hard drive enclosures.
I had a similar issue with noise, and tried the same solution (fanless mini-itx with CF for storage).
/var.
My cf card died within a couple of months, apparently from writes to the log files in
The replacement setup I did boots from CF, loads the operating system into tmpfs (ram disk if you're not familiar with it), and switches to
running on completely from ram.
In other posts people have suggested frequently backing up you email onto the CF card - if you decide to do that (and it seems like a really good idea), you should be able to get a lot more life out of your card if you dd the image off the cf card into ram, mount the image via loopback, update the files on it, and then dd it back to the disk. It's not the total number of writes to the cf device which kills it, it's the number of writes to a given block which does it in, and updating several files in a directory ends up beating on the same few sectors many times with updates to the directory's metadata.
This takes "lots" of memory, but it's pretty cheap to slap 512MB into a mini-itx box, mail is pretty small, and if that's the only thing the system is doing, you can easily fit the whole image in less than 64MB.
-eviljav
I'd go for the ramdisk idea. However UPS systems are bulky and potentially noisy, and don't protect you from some unrelated computer crash (e.g.: CPU overheating and the resulting lock-up.
Therefore find some secondary storage medium and schedule a cronjob that rsync's the ramdisk to the permament media. The permament media could be:
* a flash disk, but this time you know that you do the rsync every X minutes, and that the life of the media is Y writes, therefore you'll need to replace the thing every Z years.
* a remote server accessed via SSH
* any kind of local disk -- the tradeoff being the noise of the thing running periodically.
"But actually trying to use m4 as a general-purpose langage would be deeply perverse" --ESR
The best, quietest media is a hard disk in another room.
If you are in a studio apartment, then put the server into a large box. Underclock the main CPU. Cover the interior of the large box with foam. Put a big, slow fan in the box, and draw air in from the outside through a plenum that also has foam lining the walls, and makes at least one turn, so that there is no direct line of sight from the fan to the outside. Vent through a large, foam covered hole in the top.
Presto - silent box with as much storage as you want.
(Note - when I say "foam", I mean a low density open cell foam - something porous, like the foam they sell for use in speaker cabinets, NOT insulation panels or Great Stuff)
For the cost of a decent sized NVRAM disk, or Flash, or anything like that, you could create a HUGE RAID-5 array and still be whisper quiet.
www.eFax.com are spammers
Stick it in the closet or in a cupboard or something.
Did you use 'noatime' for filesystems on the CF drive? Obviously this won't do squat for the issue of frequent writes to /var, but it should eliminate the need to read the OS into tmpfs.
The living have better things to do than to continue hating the dead.
That's a bad idea. What happens if the system goes down after a message is received, but before the RAM disk has been backed up? The mail will get lost.
Mail servers are required to guarantee the reliability of a message it has accepted responsibility for, even in the event of power failure. In order for that to be possible, the message must be synchronously written to non-volatile storage before the server acknowledges responsibility. So unless the server operator (and any mail domains they are a backup for) doesn't mind losing mail, a RAM disk is not an option.
The end goal of this exercise is simply to prevent my poor CF card from dying an early death from continuous writes.
Don't bother with different media, just use a proper flash file system and don't worry about it. JFFS and JFFS2 are specifically designed for flash file systems, and are purely log-structured, meaning they never erase and rewrite a specific sector, preferring always to write somewhere else in order to level the wear.
To get a rough idea of what the lifetime of you CF card will be, you need to look at how much total data "churn" the card will suffer. Supposing it receives, stores and deletes 10MB of data per day, given a 64 MB CF card, the card will be completely rewritten about every 6.4 days assuming the filesystem job does a perfect job of leveling. It won't, of course, though it will be pretty good. Just to be pessimistic, let's assume that it actually does much worse, and rewrites some part of the chip once per day. That will still give you 273 years of service from your CF card, assuming 100,000 erase cycles (which is the manufacturer's *minimum* guaranteed lifetime -- you'll often see an order of magnitude more cycles before real failures occur).
If you're really paranoid about your e-mail and get a lot of it, replace the card every two years or so (which will likely be after a tiny fraction of a percentage point of the useful lifetime). A 256MB card costs less than $50 right now, and two years from now it'll cost less than dirt.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
fanless is VERY doable, just get a C3 based Mitx board with no fan and a fanless DC-DC PSU, buckets of ram and a small, quiet HD. load to RAM, and cron the /var stuff from ramdisk to the hard drive (which has /boot and /backup, while / [root] is imaged to the RAM disk. set the apm on the HD to it's highest setting and have the thing cron /var to the HD every 2 hours (or whatever suits your fancy). having a super quiet box is next to impossible without going the CF/RAMDisk route. Example: /var back every day (say, noon). if power blinks, ups keeps ram alive. assuming you check your mail several times a day you'll never have to worry.
mITX board (fanless(
fanless DC-DC psu w/ external brick
512MB RAM
128MB CF card
12v SLA/Lantern battery for UPS
mount everything to ramdisk, copy
Logistical Chaos Officer http://www.slagg.org - LAN Gaming in Sarasota FL,USA
Ohhh, it's humming again. Lousy server, wish I was deaf.
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
OK, flash based parts CF, SM, MMC, SD, USB Key, or whatever do have a finite life this is true, but the life is much longer than any reasonable use. Old parts when FLASH was a new technology had lives of 1000 cycles, and yes this is somewhat limiting. But todays FLASH is 10,000 to 100,000 cycles most flash storage controlers (for whatever format) move data arround so the "wear" on the "drive" is evenly spread across the blocks (sectors). So if you have a 64MB card lets say 32MB for software and 32MB for email/data storage and you get 32MB/day of email then the card will last 10,000 days worst case. 10,000/365 days/year = 27.4 years technology will have progressed well beyond this in this time so the machine will become useless well before the FLASH. Even if you are REAL popular and get 320 MB of mail a day thats still 2.7 years which given the price of flash and a heavy useage pattern is a reasonable price. The FLASH manufatures are guarenteeing 10,000 cycles, this does not mean that 10,001 cycles will be a failure, 10,000 is a minimum so it will probably last atleast 30% more. Even at 10,000 cycles the flash starts to fail, much like a hard disks sectors going bad and they do faster than 10,000 cycles, so some of the blocks will fail at some point after 10,000 cycles and if the controller works correctly it will pull that sector out of the rotation so the storage size will slowly decrease over time so it will have an effective size of 63MB then 62MB sometime after the 10,000 cycles. So I don't really see an issue. Some FLASH parts may fail sooner, but so may any technology and I would trust FLASH more than a HDD or RAM DISK (which goes away very quickily if there are any (ANY) power fluctuations.
Why not an iomega zip drive? I know it is not solid state, but it is quiet most of the time. It only spins up for reads and writes, it is not a constant whirring.
Regards,
Ryan Pritchard
Fun Extends All Basic Life Expectancies
Get a Seagate drive, they idle at about 30 dB, and access at about 32 dB which is right on the edge or hearing. If you can mount the thing properly it'll stay quiet (the vibration of the drive can cause more noise than the drive itself. These thing come in sizes up to 160 gigs.
Every time this issue comes up (CompactFlash wearing out) I am reminded that "CompactFlash wears out eventually", but everyone always specifies "CompactFlash"...
Do ALL forms of 'digital storage cards' have the same problem (I've always ASSUMED that they do) (i.e. "MemoryStick", "SecureDigital", etc.)? Presuming they do, does the rate at which they degrade vary, and which are the longest-lasting?
Hacker Public Radio is our Friend
Not very cool, but adequate: I bought an old 133MHz Dell Optiplex (small desktop PC) from Ebay, put Linux on it and stuck it in the cupboard under the stairs without a display or keyboard. Works fine, runs as quiet as my Tivo, and it's more than fast enough to be a web, domestic mail server, DNS and SSHD. Cost me about GBP100 for the PC and about GBP5 for an ethernet card.
Now that my first question has been answered (Thanks, cmowire), there's one more related question (not directly relevant to the original top, though).
It's been said that the "ms-dos" format used by default on CompactFlash storage is particularly bad for the chips (excessive writes when updating information on the filesystem). Are there any other commonly-available filesystems that can be recognized and used on CF cross-platform (i.e. JFFS2 appears to be Linux only at the moment) that might be less stressful to the media? UDF ("DirectCD") maybe?
Hacker Public Radio is our Friend
How about an IBM micro-drive (1GB) instead of the NVRAM type of compact flash?
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