8Gb SD card seen as only 4Gb

Hi all,

I'd run out of free space with the SD card I'd been using in my Pi. That card was 4Gb, so I decided to replace it with an 8Gb one. I dd'd the old card's contents over onto the new one and inserted it, expecting to have everything up and running with an extra 4Gb of free space, but the OS reports the new card as still only being 4Gb in total size. I'm no techie, so the best reason I can come up with to explain this is that Linux doesn't check the actual size of SD cards, it just relies on reading the partition table and since I used dd I'm guessing I've copied over the old partition table which tells the OS the card is 4Gb when it's actually 8Gb. Would that be right? If so, can I correct the error by editing the PT on the new card?
Thanks.

Originally Posted by Completely Clueless Hi all, I'd run out of free space with the SD card I'd been using in my Pi. That card was 4Gb, so I decided to replace it with an 8Gb one. I dd'd the old card's contents over onto the new one and inserted it, expecting to have everything up and running with an extra 4Gb of free space, but the OS reports the new card as still only being 4Gb in total size. I'm no techie, so the best reason I can come up with to explain this is that Linux doesn't check the actual size of SD cards, it just relies on reading the partition table and since I used dd I'm guessing I've copied over the old partition table which tells the OS the card is 4Gb when it's actually 8Gb. Would that be right? If so, can I correct the error by editing the PT on the new card? Thanks.

If you have LVM, you can extend the disk, and resize the filesystem.
What is output of: lsblk or fdisk -l

What exactly did you dd? The whole card, the partition, or the individual files? It sounds like you've ended up with a 4GB partition on an 8GB drive. The partition gets mounted and the empty space ignored. In that case, you can either keep it as it is and partition the empty space separately, or repartition the entire drive and copy across the files from the old card. Or better still, follow dc.901's advice and resize the partition.

A Raspberry pi does not use LVM. If you are running raspbian there is a configuration script to expand the root filesystem to fill the card. Must be really old since the minimum size for 8GB has been around for awhile now...

[QUOTE=Pastychomper;6175264]What exactly did you dd? The whole card, the partition, or the individual files?

The whole card: sda---->sdb

Are you running raspian?

Originally Posted by michaelk Are you running raspian?

Yes.

raspi-config has a utility to expand the root partition. If that does not work will have to think of another plan.

Originally Posted by michaelk raspi-config has a utility to expand the root partition. If that does not work will have to think of another plan.

Thanks. How do I avail myself of that feature? As you will have gathered, I'm not that clued-up on such things.

From a terminal window run the command
sudo raspi-config

It is an ncurses menu based utility, select advanced options, then expand filesystem.

I don't know if it will work but its worth a try...

https://www.raspberrypi.org/document...aspi-config.md

Originally Posted by michaelk From a terminal window run the command sudo raspi-config It is an ncurses menu based utility, select advanced options, then expand filesystem. I don't know if it will work but its worth a try... https://www.raspberrypi.org/document...aspi-config.md

Many thanks, Michael. It's getting very late here now so I'll give it a try in the morning and report back in due course.....

See man resize2fs to do it manually.