Re: A degrading micro-SD card ?

Kev,

Thank you. I was hoping for something like that.

As mentioned, I'm using a NOOBS image. AFAIK I've got zero control over which, and with which sizes it creates the partitions (it will just fill out all available space).

Besides, DD doesn't care about partitions, so I don't think that that solution will solve much of anything - unless I could somehow tell DD to stop where the last partition ends ...

....

Not what I expect to be doing on a simple restoring/duplication ...

I take it that it only backups the actual used space in the partition. If so, the actual backup would become smaller, which is a pre. On the other hand the ammount and complexity of work to restore it would increase, which is a con - especially having to recreate those partitions by hand (from what information?).

Facing that I would probably go for the simpler method, and just grab myself a handfull of identical SD cards. :-)

Thanks for the info.

Regards, Rudy Wieser

dd is pretty safe as it will stop when it gets to the end of the source or destination.

The key bit is to make the last partition a bit smaller so your image will fit on any SD card claiming to be the same size, as they can vary by up to 100s of MB.

That's easy with a normal single OS installation as it will have just the boot (FAT) and root (ext4) partitions. Put the SD card in another Linux machine and use gparted resize the last partition so there is enough space after it to allow it fir on another card.

NOOBs is a bit more complicated as it has multiple OS's and puts their boot and root partitions inside extended partitions. It is possible to resize the last root partition and then shrink the extended partition, but it's more involved.

As ever the recommendation is try out different OS's on a NOOBs card, but once you've decided which one(s) you want to use, put them on a dedicated SD card with a simple partition layout, and avoid a lot of grief.

---druck

Druck,

:-) It would be rather safe if it would continue too. Its just that on reading you get large image files, and on writing you waste a lot of time with out anything to show for.

Also, it depends on your definition of "safe" : if it stops with writing because the target (micro-SD card) is smaller than the source (image file) than you stand a good chance of an unusable, or perhaps even crashing copy. :-|

Though in my case my DD program just told me that the target micro-SD card was to small to contain the source image file, and stopped. Rightly so.

Yikes! And than just run a DD in a "just do it, ignore that its too big" mode ? That feels to me as if I'm just asking for trouble (see above) ...

On the other hand, I would not mind telling DD to include all partitions, ignoring any (slack) space after the last one though.

Hence my idea to make the NOOBS installation think the micro-SD card is actually smaller than it is ...

Do you have a bit more info about that ? I would not mind having the NOOBS pre-boot "press shift to reinstall" stuff removed.

Regards, Rudy Wieser

Dana Thu, 30 Sep 2021 12:36:24 +0200, R.Wieser snipped-for-privacy@not.available napis'o:

It knows what the size of partition is. It is written in the partition table.

You could make partition smaller. Look at resize2fs

After that you could also make partition smaller in the partition table. That way you will be able to copy from one card to another. In case you want to "reserve" the end of the card... you can make dummy partition at the end. With some kind of "weird" type your pi would not try to mount.

On Thu, 30 Sep 2021 13:54:46 +0200, "R.Wieser" snipped-for-privacy@not.available declaimed the following:

I don't think the Raspberry-Pi foundation even distributes NOOBS format any more. The closest is the "Raspberry-Pi Imager" -- which runs on Windows/Macs (and strangely, listed for Ubuntu even though R-Pi OS is based on Debian).

As I understand it, this program does a network download of the selected OS and writes just it to an SD card. One does not have the NOOBS overhead of having a couple of different OS on the card (along with the network install OS). {the imager installer is just 20MB for Windows machines -- so it obviously can not contain a 3GB OS image itself}

06/23/2021 06:27 PM 3,005,999,855

09/18/2021 12:29 PM 19,772,672 imager_1.6.2.exe

Not using an out-of-date NOOBS image might be an option...

Still won't do anything for the partition size filling the SD card -- when different brands of cards may reserve different amounts of blocks for bad-block remapping.

You'll need a USB connected SD card reader. Put a new SD card in it and connect it to the RPi.

Use the 'parted' command-line to format the new SD card with two partitions:

- partition no 1: a 1 GB fat32 partition with its boot flag set

- partition no 2: an ext4 partition occupying the rest of the card

Use the 'dd' utility to copy /dev/mmcblk0p1 into the first partition and /dev/root into the second partition.

Now the RPi should boot from the new card.

Yes, I know that the RPi OS installation is currently only 50 MB, but disk space is cheap these days and the process of upgrading the OS will require the boot partition to be at least twice the size of the installed operation system, because at one point in the upgrade process both the old and new versions are on the partition at the same time.

If you're using a tiny SD card, you can make the boot partition somewhat smaller, but don't make it less than 200GB or an upgrade may fail. Don't ask how I know this...

Lastly, if you're not already using 'apt' to do regular system upgrades over the 'net, start using it: its faster than messing round with Noobs and easy once you've done it the first time. Just run:

sudo apt-get update sudo apt-get upgrade sudo apt-get dist-upgrade sudo apt-get autoremove sudo apt-get autoclean sudo reboot

And, of course you can always save time and typing by putting that command sequence in a shell script and running that.

I always make a system backup before doing an upgrade but ymmv.

This is what gparted does graphically, in a much more friendly way and less disaster prone way than using resize2fs and parted manually.

Once the partitions are correct, you can just copy with dd, and it will stop automatically when it has filled the new card.

No don't do this, the system will object is there isn't room for this dummy partition on the new card. Just leave the space empty, then the system doesn't care if it is there or isn't there.

---druck

Not if you have resized the partitions first with gparted as I advised.

Right this is turning in to another one of these troll threads where you ask for advice, and then deliberately ignore / misinterpret it to cause a pointless argument. Pack it in.

---druck

This wont work unless the two partitions are exactly the same size on both cards, which they can't be if the new card is smaller.

If you are manually creating new partitions as above, don't use dd, but copy all the files with:-

rsync -axP /mnt/source/boot/ /mnt/dest/boot rsync -axVAXP /mnt/source/root /mnt/dest/root

---druck

This should be /mnt/source/root/ note the trailing slash or it will copy to /mnt/dest/root/root

---druck

Dennis,

That I'm using a NOOBS installation is irrelevant. My question was aimed at making *an* installation think the micro-SD card would be smaller than it actually is. IOW, changing something about the micro-SD card /before/ throwing an OS at it.

I only install from stuff I have already downloaded. That way I can re-install and have exactly the same as I did before. IOW, I rather dislike (understatement) the "just download it again and deal with whatever changes they made" approach.

:-) Don't try to tell me that removing the "repair" part is something they only thought of after NOOBS 3.5.0.

Indeed. And as I've not seen you mention anything about that in regard to whatever the latest available RPi OS version is (if-and-when it still supports my aging RPi ofcourse) ...

Regards, Rudy Wieser

Martin,

Thanks, but I'm not sure I follow. Should I understand from this that RPis 'dd' utility will automatically resize the source partition onto the target one ? Or is something else going on ?

Regards, Rudy Wieser

druck

You misunderstood what I was trying to say : You're suggesting to use a hack, ignoring the "target is too small" warning I take your 'dd' gives (mine on Windows won't even start the copy) and have not mentioning anything in regard to checking if it actually went alright. Not cool dude, not cool.

I understood your advice well enough. In fact well enough to point out to you that the result of your hack could not be trusted. And now *I'm* the bad guy ?

To use another, similar phrase : "go take a hike".

Regards, Rudy Wieser

See drucks post. The problem is that it *wont*.

create partitions manually and then transfer files as per drucks rsync cribs

I see no merit whatsoever in using DD on partitions - once you are at the file/directory level, use rsync to copy files

The merit of DD is that it copies the whole disk image. So can recreate partitions.

There's are reasons to use it, dd will copy any kind of partition correctly even ones you can't mount while rsync can be troublesome in the face of devices, sparse files, named pipes, mounts and the like. It may also be faster if the filesystem is fairly full with a great many small files.

There are reasons not to use it too, primarily that it will copy all the unused space and can only copy to a target at least as large as the partition.