Weird USB error messages on Arch Linux

April 29th, 2012

I was getting weird USB error messages on Arch Linux such as:

  • USB …. error -62
  • Along lag at boot at the “Waiting for udev events to process”
  • USB 1-2 not accepting address 2.

I have a Gigabyte 990x AUD3 motherboard and a Western Digital external hard drive.  I was running kernel version 3.3.3-1 x86_64, and after endless troubleshooting I just downgrade my kernel to 3.3.2-1 and that fixed all my problems.

USB Drives do not create a /dev/ Node on Arch Linux

April 14th, 2012

When plugging in a USB stick or USB hard drive no /dev/sdX node was being created.  lsusb and dmesg showed that the device was detected yet still no node. It turns our for me that for some reason the modules usb-storage and uas were not being loaded.

modprobe usb-storage
modprobe uas

Running the above commands as root resolved my problems and now the /dev/sdX nodes are being properly created. To make this change permanent add these modules to /etc/rc.conf.

Recovering Data from a Linux Software Raid 1 Array

September 15th, 2011

To recover data from a Linux Software Raid 1 Array assuming no logical volume management (LVM) is present.  Use the following command to mount a single disk from the array:

mount -t ext4 -o ro /dev/sdX /mnt/destination

The trick is to tell the mount command what type of file system the partition actually contains. Mount it read only so you do not mess up what could be your only remaining backup copy of the data.