How can I resize my / (root) partition?
Even though my SD card is 16GB, the image I flashed onto it was only 2GB and now I can only see 2GB of storage space on the disk.
How can I resize the image so that I have more space on my root partition?
Thanks..worked great for me and didn't tank my system..still have IRC and apache webserver and my full 8gb capacity
Why resize a root partition when you can create new partition at the remaining free SD-card space and then mount it inside the root partition at `/mnt/storage` for example. This effectively isolates system and data and makes it easier to maintain and backup.
@mbaitoff - because the default system image only has 68MiB free space, which doesn't leave much room for adding additional software.
@Jules - I wasn't asking why one would want to resize a partition. A was asking why would one resize the system partition instead of mounting additional storage at system partition mount point thus effectively isolating system and software/data? If you want storage, mount remaining SD spcae at `/mnt/storage`, if you want programs - mount at `/opt/software/`.
@mbaitoff most programs install in /usr, not /opt/software. The prebuilt images have the contents of /usr in the root partition. It therefore seems essential to increase the size of the root partition if you want to install any non-default software.
Assuming you are using Debian.
The Short Version:
- Backup your system
- Remove the main and swap partitions (leaving the boot partition alone)
- Recreate the main partition to utilize the remaining disk space (excluding the boot partiton). Make sure to reuse the same start sector as the original root partition.
- reboot the system
- resize the new boot root partition to utilize the full partition size.
Step by Step Instructions
First make a backup of your SD Card using the instructions found here in case something goes wrong.
From the command line or a terminal window enter the following
sudo fdisk /dev/mmcblk0
pto list the partition table
you should see three partitions. if you look in the last column labeled System you should have
- W95 FAT32
- Linux Swap
make a note of the start number for partiton 2, you will need this later. though it will likely still be on the screen (just in case).
dto delete a partition.
You will then be prompted for the number of the partition you want to delete. In the case above you want to delete both the Linux and Linux swap partitions.
dagain and then type
3to delete the swap partition.
Now you can resize the main partition.
nto create a new partition.
This new partition needs to be a primary partition so type
2when prompted for a partition number.
You will now be prompted for the first sector for the new partition. Enter the start number from the earlier step (the Linux partition)
Next you will be prompted for the last sector you can just hit enter to accept the default which will utilize the remaining disk space.
wto save the changes you have made.
Next reboot the system with the following command:
once the system has reboot and you are back at the commandline enter the following command:
sudo resize2fs /dev/mmcblk0p2
Note: this can take a long time (depending on the card size and speed) be patient and let it finish so you do not mess up the file system and have to start from scratch.
Once it is done reboot the system with the following command:
You can now verify that the system is using the full capacity of the SD Card by entering the following command:
Why This Works:
The real magic here is that you delete the root and swap partitions, then recreate only the root partition (using the original start sector) before writing the data to the disk. As a result you don't erase the existing data from the root partition.
By removing the swap partition you allow the root partition room to grow beyond its current size and fill the unused portion of the disk (because of the placement of the partitions -the root partition is sandwiched between the boot and swap partitions - it can't simply be resized leaving the swap partition alone).
You then resize (which is safe to run on a mounted disk) the file system to use all the space in the new root partition.
A good answer. But this will still only give a maximum of 2GB I believe, the size of the image.
@Jivings check the linked reference for proof it works - also I did this before putting xbmc on the pi.
@finnw It looks to me like this method deletes the root partition so that it can be recreated larger, which is not really optimal.
@finnw You can see more evidence for this method here http://www.raspberrypi.org/phpBB3/viewtopic.php?f=5&;t=5584 as well as an asnwer to your resize2fs question.
@Jivings if done correctly you don't lose a thing, but it is the reason I made step one backup.
From the comments it seems like you should also document **why** this works, not just how.
It seems very wrong that you have to delete a partition in order to resize it.
@AlexChamberlain I think if the command was resize (it is actually called resize in Windows) partition rather than delete partition this would go down a little easier.
This really felt like complete spine replacement surgery (with leaving old spinal cord in place) on a live patient without using anesthetics or even interrupting their daily routine, but surprisingly, it worked just fine. If you're scared, do it on a newly-flashed card, which you can flash anew if anything goes wrong; also you might want to create a swapfile and mount it, since the swap partition got removed.
I've been using this process like forever without any problem, however the latest images from arch linux arm changed the partition structure, so you can't follow the above instructions in a 'copy-and-paste' fashion, I found the updated instructions in this website: http://jan.alphadev.net/post/53594241659/growing-the-rpi-root-partition, this works for me.
@Couto if that is the case please post an answer with the steps for arch?
Wait, how do you do that on a Mac? I am trying to install Raspbian again on my sd card but I have formatted it several times with the erasing kind of formatting and it still does not seem to be gaining any memory.
@AwesomeUser You don't do it on the mac, you do it on the pi itself. Also, if you are running raspbian you can boot the pi and from the command line issue the following command sudo raspi-config, and choose the resize root partition option.
What if you actually like your swap partition, and would like to recreate it after following these steps?
@zaz, that is really a separate question and should not be asked in the comments of an answer.
@SteveRobillard the question was "how can i make my root partition bigger" - not "how can i make my root partition bigger and as a bonus remove my other partitions"
@zaz and that is why it should be a separate question. Click the ask button above and ask about your swap partition. New questions do not belong in the comments especially to old questions. By asking it here the only person who is likely to see it is me. if you ask a new question the entire community will have a chance to see and answer it. Also, note that depending on the OS/distro you are running Raspbian for instance includes a script to resize the root partition, and does not need to be done manually.
I know how to create a swap partition, what I'm saying is you should add "leave space for swap partition" and "fdisk another swap partition to replace the one deleted in step 2" to the answer, because the way it is presented currently makes it look like the swap partition isnt neccesary.
Actually it would probably just be enough to post a link to http://raspberrypi.stackexchange.com/questions/70/how-to-set-up-swap-space or something, and make a remark along the lines of "We removed the swap partition, but those are a bad idea on a raspberry anyway because sd card."
I tried this on raspberry pi3 but I am getting this error after reboot: `PANIC: VFS: Unable to mount root fs on unknown-block(179,2) Entering kdb (current=0xcb82ac80, pid 1) due to Keyboard Entry`.
@haccks First you should not ask new questions in the comments to another question. Second, assuming you are running Raspbian did you not use raspi-config to do this. As you have learned this way can bork your system if not done correctly. I would suggest re-imaging your card and starting fresh.
@SteveRobillard; I am not asking a new question. I came out to this answer and gave it a try. And I am using Kali image instead of Raspbian. I wanted to know how to do this using CLI ( earlier I used `gparted`).
Can this be done on a PI to shrink instead of grow a partition? (While doing that on the same PI).
@clankill3r Maybe, but I would not recommend it, as it can potentially destroy your system. A search here or google will turn up complete instructions for shrinking the size of the disc image.
For NOOBS partitions, the partitions would be e.g. primary "1", and extended "2" that contains the **logical** partitions "5" (`SETTINGS`), "6" (`/boot`) and "7" (`/` root). Make sure you select "7" and **logical** as partition type when creating the new partition. For more check this tutorial.
@Steve Robillard Thank you Steve, this worked like a charm! After failing to resize from another OS and messed up the installation, I tried this method. It is the right method to resize. We don't need to remove and move the card to another system just to resize a partition. Great work!
I did: `sudo resize2fs -p /dev/mmcblk0p3` and got `resize2fs 1.43.3 (04-Sep-2016) resize2fs: Device or resource busy while trying to open /dev/mmcblk0p3 Couldn't find valid filesystem superblock.`
@EliaWeiss are you running noobs? What distro are you using? Is the filesystem already expanded?
@SteveRobillard Please see more info in https://raspberrypi.stackexchange.com/questions/82585/resize2fs-device-or-resource-busy-while-trying-to-open-dev-mmcblk0p3
@Steve Robillard Thank you Steve. Just one complementary information, in my case I use a RPi2, I boot on the SDCard and use an external HD as /, so disk path is /dev/sda2. Plus I have no swap partition ...
Great answer! Would you mind adding something about deleting the signature?
Same here! After creating the partition (i.e. enter the number of last sector) it asks me "Do you want to remove the signature? [Y]es/[N]o: "
An easier CLI option is to open `fdisk mmcblk1`, choose `O` to dump the disk layout to a local script, and back it up. Use `p` to get the number of sectors on the disk, and in each partition. Sum up the `Sectors` values for partitions you want to keep, and subtract them from the total. Now edit the script, and use that number for the `size` of the target partition. Save it, use `I` to load it into `fdisk`, and write your changes. Use`partprobe /dev/mmcblk1` instead of rebooting and, finally, `resize2fs /dev/mmcblk1p2`.
Using the Debian-Wheezy Beta image, there is a configuration utility built in that makes this easy:
There is a utility called
raspi-config. This runs on first boot if you're connected directly to the RPi. If you're over SSH you can run it manually using
$ sudo raspi-config. (I think you can re-run the tool manually at any time).
The second option on the blue dialog that follows is titled
expand_rootfs, with the description "Expand root partition to fill SD card".
Selecting this will cause your root partition to be resized to fill the card the next time you boot your RPi.
Update for 2015!
I'm coming back to this answer with a note of caution: I have been using a bunch of 16GB SD cards, and I got caught out by maxxing my partition to fill the card I was using. Doing so caused a bunch of problems when switching to a new card which (even though it was stated as 16GB) was about 200MB smaller than the older card.
This came to a head when I switched a couple of RPis from v1 to the new v2 model, which uses Micro SD cards.
I now leave about 1GB free to make absolutely sure that my images can be switched between SD cards without issue.
@JamesSkimming: This is the solution to use for Debian-Wheezy Beta image. Not for others.
This doesn't work for Raspbian when installed from NOOBS on the SDCard's they're shipping with RPi kits. when you try to run the expand option it says that it's not supported by this config, but since your running noobs it's probably using all the space anyway... problem is I'm trying to reflash the 8GB image onto a 32GB Card
Raspi-config doesn't know how to resize root of Raspbian Wheezy. expand_rootfs as you suggested caused issues. The answer above yours works like a charm in a live system and no need to "leave about 1 GB".
For anyone using Plex and moving your sd card files to a larger sd card, this worked great after copying the new image.
If you are not very comfortable working on the command line, like in Steve Robillards excellent answer, there are some GUI applications available. In particular gparted works very well.
I think it's installed by default on a Ubuntu LiveCD but not on an installed system. There is of course an easy fix for this:
apt-get install gparted. You can't do this on the actual Pi, because to resize partitions they need to be unmounted.
The picture below is in Dutch, but don't let that spoil the fun. It's very easy to use. This is the layout of the default debian image on a 8gb sdcard.
Right-click the partions to unmount them and then right-click to resize or move the partition. You can also create new partitions and format existing ones. In the picture below I've removed the swap partition and now I'm able to resize the root partition to the entire space on the right of it. Don't fill it entirely, because you still have to add a swap partition.
You can play with the partition layout, changes are only written if you apply the changes (the grayed out 'return' key in the first picture).
It's very easy to move partitions but like in Steve's answer I'd recommend you remove the swap partition entirely, then resize the root and then recreate a swap. Moving a partition can take a very long time and the swap does not contain data you need to keep.
If you use the newer Debian Wheezy image: http://www.raspberrypi.org/archives/1435 A boot-time script allows you to resize to fill the sdcard automatically.
How would do such a thing though?
I followed this video and it worked perfectly for me (I have a 16GB card):