Linux tcp tuning:
http://www-didc.lbl.gov/TCP-tuning/linux.html
Generate random numbers on linux:
dd if=/dev/urandom bs=1 count=128 | od -x
Solaris:
psrinfo -v lists the processors on a box
Re-format external USB hard-drive
Motive: I wanted a backup solution that preserved file permissions when using rsync with the
-a option.
My Western Digital usb drive had a vfat file system - which doesn't preserve file permissions.
This is what you'll need to do in order to convert to an ext3 file system:
When you plug the drive in check
dmesg to find out which /dev device it's been mapped to. I found mine under /dev/sda1.
Then you'll need to partition the disk:
fdisk /dev/sda1
This will give you a command prompt interface. Type
p to get a list of the current partitions.
I had 4 partitions, so I deleted them all using the
d command.
Then create a your partition(s). I created 1 great big extended partition using the
n command. It asks you a few questions about block sizes etc, I chose the defaults.
Then I typed
w to write the partition data to the disk. Then I quit fdisk.
Then I created the filesystem:
mkfs.ext3 /dev/sda1
It asked me a few questions, I excepted all the defaults.
Then you're ready to mount the device:
mount /dev/sda1 /mnt/usbdrive
You'll have to create the folder /mnt/usbdrive yourself.
So that the disk gets mounted on reboot add the following line to /etc/fstab:
/dev/sda1 /mnt/usbdrive ext3 defaults 0 0
This also means you can simply type:
mount /dev/sda1
when mounting the disk from the command line.
to top
