Silent, Durable Media For Servers? 50
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?"
Ramdisk (Score:3, Informative)
Re:Ramdisk (Score:3, Interesting)
Re:Ramdisk (Score:4, Insightful)
Better yet - you already have it working with the compactflash setup, yes? It already work, and you already like it. And it works. And you have it working.
Did I already mention that it is working?
If it works and you are happy with it, don't fsck with it. You understand the limitations of the media, so work those into your maintenance cycle. 64M CF cards are cheap, so replace it every year, even every 6 months (or better yet, keep a spare and replace it when it starts to show damage, if there is a way of checking
Oil is pretty good at lubricating a car engine, but it needs to be replaced every 3500 miles.
Batterys are pretty good at storing power so you can start your car, but even they wear out and need to be replaced every couple of years.
CompactFlash is doing exactly what you want, but it needs to be replaced every once in a while - so keep using it, and replace it every once in a while.
I am about -:- that close to replacing the hard drive in an older laptop with a CF solution, I just need to wait for the 1G cards to come down in price a little - or wait for the Win2000 version of 98lite to go live so I can buy it (and fit Win2000 plus apps in under 512M of flash-drive.) The thought of a laptop that is silent, with no moving parts, and totally immune to me flopping it around while it is running (without worrying about gyroscopic effects on the drive) simply thrills me.
As usual, more than one way to skin this cat. (Score:5, Informative)
Barring a regular hard drive, the first and most obvious method is a solid-state disk [google.com] 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 [siliconacoustics.com], 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 [foambymail.com] 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!
Re:As usual, more than one way to skin this cat. (Score:2, Informative)
For laptop drives, in my experience, IBM laptop drives are pretty loud (as laptop drives go), but Fujitsu's laptop FDB drives (specifically the MHS series - i.e. MHS2030AT) are very quiet.
-eviljav
RAM disk is no good for a mail server (Score:4, Insightful)
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.
Re:RAM disk is no good for a mail server (Score:1)
If you used a ups backup , just one that could sustain mybee 5 or 10 min most. Then user a program (sure theres one for linux) that moniters the ups , if it turns on becuase of power out , AUTO backup
But i still see the problem , ramdisk would be cheap but a lot of hassle
Email is important -- you want redundancy (Score:3, Funny)
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 [8k.com]
You might especially look in to this variation [8k.com]... ;)
JFFS2 (Score:1, Interesting)
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).
Location, location, location. (Score:1)
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
Put /var elsewhere (Score:2, Interesting)
Don't be afraid of CF disks (Score:3, Informative)
Re:Don't be afraid of CF disks (Score:1)
Jane, you ignorant slut. You obviously have no idea what you're talking about. CF cards have an IDE mode that does *not* do wear levelling. You need a CF ide disk to do that. Otherwise you can use a CF card in an IDE adapter but you will have to use a filesystem like jffs/jffs2 to handle the wear levelling.
usb key? (Score:3, Interesting)
Re:usb key? (Score:2)
Ensure it is USB2.0 and you will have more than enough speed and up to 1GB (last I looked) available per stick.
They don't suffer from the rewrite limitations of the CF cards.
The only difficulty I have had was creating a system that adequately secured the USB stick, as it was not meant to be portable/stealable like my usual USB key. In the end I mounted it internally using an additional internal USB port and a hacked cable mount.
Q.
Re:usb key? (Score:2, Informative)
Re:usb key? (Score:1)
Re:usb key? (Score:1, Informative)
Old laptop (Score:3, Informative)
Via C3 (Score:2)
Microdrive? (Score:1, Interesting)
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
enclosures (Score:4, Informative)
My solution (Score:3, Informative)
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
noatime? (Score:2)
Re:noatime? (Score:1)
Sticking the whole operating system into tmpfs has worked out fine though, the system image fits in less than 24MB, so the box has over 400MB free...
-eviljav
Re:My solution (Score:2)
As of yet the whole 'CF card dying' thing has been purely speculation, I have been dying to find out how it actually plays out.
Re:My solution (Score:1)
Re:My solution (Score:2, Informative)
It didn't show up as the drive shrinking, (that would have been neat), it was losing data - e2fsck errors, occasionally corrupted log files etc. Eventually I tried testing it by doing things like "dd"ing an image off of it, formatting that image via loop back and "dd"ing it back, and finding errors on the newly written drive.
At that point, I gave up
ramdisk with a cronjob (Score:3, Insightful)
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.
The best, quietest media (Score:2)
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
Put the computer in a closet (Score:1)
Stick it in the closet or in a cupboard or something.
Don't bother (Score:5, Insightful)
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.
Re:Don't bother (Score:2)
My solution is to pack a low power server (cobalt qube2) with a large disk away into a closet and let distance and doors keep it quiet.
Re:Don't bother (Score:2)
My solution is to pack a low power server (cobalt qube2) with a large disk away into a closet and let distance and doors keep it quiet.
Different answers for different folks. The guy asking the original question thought 64MB was enough.
I'm like you, my Maildir is huge... just shy of 3GB, actually.
Re:Don't bother (Score:1)
Also, just buy a bigger card and you'll reduce the number of cycles. With a 64M card half full, you'll cycle through the other half of the card twice as fast as if you kept it mostly empty. Same 32M of data on a 128M card will cycle 1/3 as fast relative to the 64M card, a 256M card will
uber-silent = hard to achieve (Score:1)
mITX board (fanless(
ObHomer (Score:2)
Flash Life Myths (Score:4, Informative)
what about an iomega zip drive? (Score:1)
Seagate Barracuda (Score:1)
Probably a stupid question, but... (Score:2)
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?
Re:Probably a stupid question, but... (Score:2)
A related question... (Score:2)
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 stress
Media alternative (Score:1)