Whenever I try to update my pi using sudo apt-get update && sudo apt-get upgrade it will often hang at some point during the installation. It's been different ones each time, but the last was pulse audio.

Furthermore, I am able to ping the pi and an ssh appears to connect, but never gives me a prompt. I've had another terminal open at the same time and top shows the CPU around 90+%

Has anyone else encountered this?

I can attach logs once I am able.

  • I have almost the same issue: the sudo apt-get upgrade procedure stopped at some moment. And after that I can not connect to my RPi via SSh. But I can still have access to my server test page. The ACT-led is shining all the time. And this continues for 3 days.
    – user7445
    Commented May 16, 2013 at 20:51
  • I've had this twice now. It wasn't an out of memory option, as described below. Yesterday, it hung for a long time on some package during the upgrade process, and I was able to switch to a new window in tmux and run free -m. There was still about 300M free and no swap in use. Currently, it's hanging and has been for 10 hours. It's not just an issue with OS unresponsiveness during disk flush.
    – Halfgaar
    Commented Jan 11, 2014 at 10:20

2 Answers 2


I also had a problem with a hanging update. The reason was the power source. I had a 400mA power source that was to low for the RaspberrPi. I've changed to 1000mA and it was running nicely. Perhaps you can check that?

  • It seems to be my problem! With another power source everything is OK. Commented Oct 5, 2014 at 10:47

Updating the system is an I/O-intensive operation. The OS does not immediately write data to the SD card, instead it will buffer it in the RAM. At some point, it will try to write these buffers to the SD card. Since the SD card is not fast enough the OS will look unresponsive when flushing buffers.

Another possibility is that your system is running out of memory, thereby causing swapping. If you do not have swap space, the OS will start killing random processes. If you do have swap, but on slow media, it will still take some time before processes can continue.

  • Would you suggest transferring the OS to the HDD that is attached and only using the SD card for boot then?
    – whotyjones
    Commented May 11, 2013 at 0:01
  • @whotyjones That is a possibility, but personally I would just get a fast SD card from a well-known brand and update the system when daemons and GUI are closed. (I have the SDSDU-008G-U46, 8 GB myself for €9.00)
    – Lekensteyn
    Commented May 11, 2013 at 8:17
  • I'll order one and see how it works. It's something I'd considered but I didn't think it would cause that much of an issue.
    – whotyjones
    Commented May 12, 2013 at 21:32

Your Answer

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

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