IT Troubleshooting

Computer Beeps and Fails to Boot

Every motherboard and BIOS has its own special beep code.  Check the motherboard manual for details on the beep error codes (short, long, continuous, intermittent, etc) to narrow down the bad or missing hardware.

Some of us have he ASUS 9X79 Motherboard.  When it fails to find a boot device, it makes what sounds like a continuous stream of short beeps.  You will not find this in the manual.  What you will find in the manual is the listing of the motherboard LEDs.  When a component is tested upon startup, the corresponding LED lights up.  The last LED to light up before failure indicates which system has failed.

In one instance, the boot-device LED was the last to light up before the motherboard started to beep.  As further proof that the boot-device was at fault and not other components, the user could get into the BIOS, move around with keyboard and mouse, and list all components (CPU, motherboard, etc).  However, when the user continued and tried to boot, a black screen with a flashing “_” cursor and motherboard would beep.  Also, the user was able to boot using a valid live OS CD, further indicating the hard drive containing the boot loader was corrupted somehow.

The Fix:

Backup all data.

Boot using a valid live OS CD.  Find out the drive containing the old root directory.  Make a new directory on the live CD file system.  Mount the old root directory into that new directory.  Mount another hard drive to store the backup of the old root directory.  Copy all the necessary files from the old root directory to the extra hard drive.


boot repair is a GUI for repairing grub and other boot loader related files.  It works on ubuntu.  Rewrite the grub loader on the drive containing the corrupted boot loader.  Restart.

How do I Find the Last Updated File When There are a Bazillion Files in a Folder

Say you want to find the last updated file using wildcard for the filename.  Normally, you can type

ls -lht *.fasta

in order to list all the files and sort them by last modifed time.  However, ls starts to slow to a crawl when there are more than several thousand files in a folder.  Also, the ls commandline expands all files matching the wildcard and might hit the maximum command character limit.

A better way to do this is to use the find command and pipe it to sort:

find /parentfolder/ -type f -name "*.fasta" -printf '%T@ %p\n' | sort -k 1nr | head

How Do I Find My Motherboard and Bios Model Remotely?

No need to physically open your machine to find your motherboard and bios model.  Simply execute the following on the terminal commandline:

# [ -f /usr/sbin/dmidecode ] && sudo -v && echo -n "Motherboard" && sudo /usr/sbin/dmidecode -t 1 | grep "Manufacturer\|Product Name\|Serial Number" | tr -d "\t" | sed "s/Manufacturer//" && echo -ne "\nBIOS" && sudo /usr/sbin/dmidecode -t 0 | grep "Vendor\|Version\|Release" | tr -d "\t" | sed "s/Vendor//"
Motherboard: Supermicro
Product Name: H8QG6
Serial Number: 1234567890

BIOS: American Megatrends Inc.
Version: 080016 
Release Date: 05/27/2011


How do I tell how many PCI slots are available remotely?

You don’t have to pop open your server to find out how many free PCI slots you have. Simply run “dmidecode” as root on a remote terminal.

$ sudo dmidecode -t 9 | grep -E "DMI type"\|Usage\|Type
Handle 0x0008, DMI type 9, 17 bytes
    Type: 32-bit PCI
    Current Usage: Available
Handle 0x0009, DMI type 9, 17 bytes
    Type: x8 PCI Express
    Current Usage: Available
Handle 0x000A, DMI type 9, 17 bytes
    Type: x16 PCI Express
    Current Usage: Available