Hello,

I am halfway to solving a long standing problem since I upgraded to Hardy.

Background to the Problem:

I currently have Linux Mint Elyssa installed on my Packard-Bell desktop system 2gb ram, Pentium D, nVidia G72 G-Force 7300 SE. I moved to Mint because I enjoyed Ubuntu (my first love) but at the same time this problem was driving me nuts and I had to try out another distro.

The problem I kept having was whenever I plugged in my fat32 500gb external hd and started copying large files the whole system would freeze - it would not even respond to my attempts to raise Skinny Elephants. Googling this forum produced many different results and theories but I couldn't access logs due to the freeze at the time and I tried some of the solutions but to no avail.

Linux Mint was very good at first, it was working fine when I attached the external drive and would copy many large files. Now the problem has started happening again almost exactly the same...

The Problem:

When I plug in my external drive, before it mounts the whole system freezes, just as before on Ubuntu, however I have discovered if I log off completely before plugging in the external drive, it will mount and work fine (but will crash if I try to copy multiple files more than ~1.5gb).

I have done a bit more digging and research and may have discovered the culprits, and this is where I need the help of the brains of this forum.

I have a Belkin 4-port usb 2.0 hi-speed hub attached to my pc which in turn has 6 usb 2.0 ports directly attached to the motherboard. I noticed a number of things:

  • When I plug in a flash memory stick, the system does not mount/recognise it (previously it did). However if I do the following first it will automount:
    Code:
    sudo rmmod ehci_hcd
sudo modprobe ehci_hcd
  • I can mount unmount and plug in the flash memory drive in this way, but as soon as I start Vuze (which is a java based app) I can plug in and mount once but if I remove the flash memory or the hub and plug in again the system will freeze up
  • Whilst the Belkin hub is plugged in, I have problems with my external HD in that it freezes like this regardless of running Vuze.
  • When I plug in the flash memory to one of the motherboard usb ports, or unplug the Belkin hub and plug in the external drive then there is no freeze, whether I am running Vuze or not.


So there appears to be 2 seperate behavioral problems between my flash memory, external hd and Vuze (java) but they both relate to the Belkin 4-port usb hub.

My questions are these:

  • Is there a problem with Belkin 4-port usb 2.0 hi-speed hub and Ubuntu which causes the system to freeze like this?
  • Is there a way to record the logs like dmesg before a system crash? - I know exactly how to evoke one now. Are there any other logs I can get info from?
  • Am I understanding right that ehci_hcd is the usb 2.0 module which I am restarting? If I disable this, the usb devices seem to work normal - does this mean I have to use usb 1.1?
  • Has anyone else experienced this and have a solution other than disabling usb 2.0 or logging off to plug in usb devices and logging back on?
  • Ideally I'd like to find out why it was working when I first installed Mint but then the problem came back (without doing a fresh reinstall).. does anyone know what I should be looking for?


Thanks in advance for taking the time to read through this and answer!