3

I ve seen many recipes for a longer lasting SD, but no one convinced me that this is not a tremendous flaw in the whole Raspberry concept.

Targeted for students, packaged with N.O.O.B.S., etc, it become clear the newbie's happiness will last a month, and then, corruption. What a welcome message!

In the past, we could buy battery powered compact flash cards for the ancient HP200LX, plug it and forget about for, say, 10 years (changing batteries every two years).

The best reliable solutions proposed in this site refers to minimizing writes to the disc, strapping vital functions and rendering the RPi almost unusable, even forgetting that the kernel itself will write countless times in the same sectors due to the linux file abstraction model ( everything in linux is a file).

That said, while manufacturers do not present an everlasting solution, is there another kind of SD Card electrically compatible solution or hacking that would bring Raspberry to the serious side, without inflating its size and purpose?

Improve this question
3
  • 4
    I have had mine for over a year. No corruption? And I use it frequently for experiments. But I do use an original Kingston SD card I bought separately. You do ask a very interesting and feasibly good question though, as it would be nice to have something a bit more reliable in the long run. +1
    – Piotr Kula
    Sep 16, 2013 at 22:34
  • Ok, I don't understand how sheepishly people accept a so low a standard as to go round and round remedying it for the sake of fun. SDCard corruption is a flaw in design, so people lets get to work! Real needs wait for a computer this size (but working). No one of us work in a project of a regular RAM, SDCard Sized, battery backed, to put in place and open the real world for Raspberry Pi?
    – m33600
    Sep 16, 2013 at 23:48
  • Btw. have a look at Intels bid to the market which includes a SATA controller: arstechnica.com/information-technology/2013/09/…
    – Kenneth
    Sep 20, 2013 at 8:42

4 Answers 4

Reset to default
7

You make a lot of assumptions. The statement about 1 month is just flat-out wrong.

Compact flash cards are actually worse for this kind of operation than SD-cards. I tried to install a server onto one which lasted a whole three weeks before dying. Compare that to the server I have running on an SD card on the pi for over 3 months now 24/7. But no, there are no guarentees how long it will actually last.

Many SD-cards use middleware to ensure that writes do not happen to the same sector but it is a bit of a mystery which manufacturers provide it with their cards and this is the cause of most of the confusion with SD cards for the pi.

Another option is to use the SD-card for the boot loader and keep your distro and a USB hard drive. This however will inflate its size.

Lastly the pi is not meant as an everlasting solution. Neither is the beagle board or the Via APC (which both run of micro-sd cards). If you want a full-fledged desktop system, get a pc of your preferred form-factor (via is a good option). The pi is a development platform and should be used as such.

Improve this answer
4
  • Development platform for what? No product we use came from there, did it? I believe it's like a welcome platform, remembering us to get back to hardware times. And in the internet of everything, IoE, RPi is kind of a protagonist. It should last reliably for as long as my eeepc at least. That's my point. Is it definetly not an adressable issue or there is some type of SSHD that would solve the problem?
    – m33600
    Sep 16, 2013 at 23:34
  • SSHD? No. But you are kind of missing the point. A good SD card with good middlewear and ample space will last as long as a SSD, which incidentally has the same drawbacks if not using TRIM. The SD choice is the best option regarding prototyping and price - the pi's strong points. And no, no products we use is implemented directly on the pi. Plenty of products uses FPGAs but no products we use is based on an Altera Cyclone development board.
    – Kenneth
    Sep 17, 2013 at 7:09
  • Maybe the two of us are missing the point. I don t think in terms of mass production, but a seriously tailored application left in place after proof of concept. As an example, a garage door opener, taking pictures and uploading to a website on every open/close cycle. IMHO RPi does the job natively, plug the camera, script, connect and interface with the sensors and relays. A celeron PC would fit well for the task. But you tell Raspberry wouldn t. Is it the concept of prototype we are discussing here? If so, every computer becomes a prototype at the moment you turn it on and personalise. Is it?
    – m33600
    Sep 17, 2013 at 15:53
  • My point is that it depends on the purpose. If you want a device to run 24/7 with aggressive writes, then a SD card is a bad option. But so are flash drives which have limited write cycles as well. RAM disks are a far better option. If you have a limited system like a garage door openor that mostly works in memory anyway a SD card with the proper precautions is perfectly fine. In the end, if you trust flash memory more than the SD card, have a look a via's APC. It offers 4GB of onboard flash.
    – Kenneth
    Sep 18, 2013 at 6:17
3

Well, the welcome message for a newbie would be a kind advice indeed: always do backups.

I've experienced two or three SD failures (even from "famous" brands) and the corresponding loss of hours and hours of configuration work.

Now I settled with two cards running 24/7 on two RPi's that didn't show a single hiccup, but this didn't prevent me to build, run & test a daily backup system for both systems (and my laptop too) to an external HD. And since I'm perfectly aware that the HD too will fail someday, I'm planning to add redundancy with another drive.

The only effective way to bring any piece of computing to the "serious side" is to make backups and/or making it redundant.

Improve this answer
1
  • Understand. I was to adopt a cluster of 32 RPi, for a new building I'm designing, but cannot stand the idea of changing SDCards weekly. Let me conceive a "normal size" room and 10KW nobreak for the time beeing...
    – m33600
    Sep 16, 2013 at 23:39
2

There are many cheap and small USB pen drives in the market, it's a pity the Pi won't directly boot from USB. I assume that another USB socket/bus would raise the cost of the Pi too much. On the counterpart, not having to buy a new SD every month is a money saver.

IMHO USB pen drives are more reliable than SD card. No benchmarks, just my experience.
I really hope for a "model C" Raspberry Pi with dedicated USB boot.

Improve this answer
3
  • 2
    Good idea for the model C. I'm pushing this conversation up to find a way out of "would be" projects. I believe RPi is as good an electric circuit as any, and should work and live alike. But people are making me believe that, after any idea implemented over RPi, I'll have to redesign a board, change the storage method, etc., because current state of the art does not suffice. For me it's like killing the baby after proving the wife was fertile.
    – m33600
    Sep 17, 2013 at 16:15
  • 2
    You can boot from a USB stick if you use an SD card for the initial part of the boot, having the SD card do a small amount of reads when the Pi is first powered up and almost nothing else during operation would make the cards last longer. But I agree that it would be nice for this to be a native feature of the Pi.
    – user8894
    Sep 18, 2013 at 9:28
  • @Dan that's exactly what I'm doing, but I have to keep backups of 2 images for each Pi, one is the USB pen drive, and the other is 2 GB of SD card, which only the first 50 Mb or so are useful (/boot partition). I am wondering how difficult would be to insert a small hardware selector to boot from SD or USB.
    – Alessandro Da Rugna
    Sep 18, 2013 at 9:43
2

You don't actually need to write to the SD Card at all, or at least not much after the initial configuration. Depending on the application you have in mind.

We use the RaspberryPi in a system we ship to customers and we configured the SD Card to be mounted read only with a union file system on top. The downside you lose any changes after a reboot, the upside, you can't corrupt a read only SD card with failed writes.

Have a look at http://blog.a-netz.de/2013/02/read-only-root-filesystem/ for a guide on how to do it. You can remount the filesystem RW if you need to make changes and then mount it RO when you are done.

The SD card will last approximately Forever(TM) in such device because they aren't ever really being written too.

It makes the system less flexible, but you can yank the power from it and never be worried about a file system corruption.

If you need writable storage that can't be lost then the use of NFS or SMB mounts to copy to could solve that problem.

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.