Posts tagged "linux"
Debian 8 Uses only One Core of a Multi Core CPU
Problem: A fresh installed Debian 8 (Jessie) 32bit 686 uses only one core of a 6 core Xeon CPU. amd64 kernels don't have this problem. Solution: The HP Proliant DL360 Gen9 has a BIOS option called "Processor x2APIC Support". When you set this option to "Disabled" the Linux kernel uses all 6 cores. x2APIC is a new co...
Wget Ignores its Timeout
Problem: wget has an option to configure the timeout for dns, connect, and read or a combined timeout option "-T". This option usually works, but it does not work during SSL handshake. You can test it with these commands: in one terminal start a dummy tcp service: nc -l 7777 and then try to connect to this service: ...
Mapping Mouse buttons to Commands
New mice often have lots of buttons. Some buttons are used by X and some are used by Applications: 1,2,3: Left, middle and right mouse button 4,5: Y axis mouse wheel 6,7: X axis mouse wheel 8,9: Foward and backward in browsers usually But other buttons are not mapped to any function mostly. My Mad Catz R.A.T.5 mouse...
Openbox goes weird with R.A.T.5 Mad Catz
Problem: when you connect the Mad Catz R.A.T.5 mouse to a Linux box running openbox window manager, the window handling stops working. Sometimes mouse follow focus does not work, sometimes even clicking a window cannot activate it. Sometimes clicking window borders does not work, sometimes clicking into windows is i...
USB SCSI Disconnects when Idle
Problem: An external USB harddrive disconnects and immediately reconnects with different device name. You find log entries like these: Jan 17 00:46:52 workstation kernel: [212306.086568] sd 33:0:0:0: [sdj] Attached SCSI disk Jan 17 01:51:14 workstation kernel: [216168.064075] usb 2-4: USB disconnect, device number 1...
1:1 Copy of Hard Disks with Errors
Problem: When you get I/O errors on your computers hard disk, it's usually urgent to copy all data to a new disk. If you try to do a 1:1 copy using dd, you will see that dd stops when it reaches the first bad sector. Solution: use the following command to copy from one hard disk to second hard disk, with every bad s...
"dd" shows its progress
Problem: "dd" is a useful tool on linux . E.g. you can copy a disk image or wipe a disk, etc. But dd doesn't show you any progress indicator, and you don't know how long you have to wait until it has finished. Solution: send signal USR1 to the dd process and it will show you how much data it has already transferred ...
Howto generate an SSL key and self signed cert with openssl
For SSH, HTTPS, TLS SMTP,POPS, IMAPS you need a RSA key pair. Most Linux package installers produce this pairs automatically, but if you like, you can generate them yourself. The quickest method I found is: openssl req -x509 -nodes -newkey rsa:2048 -keyout servername.key -out servername.crt -days 1024 This command a...
Unix/Linux date command fails when calculating "yesterday"
Problem: A shell-script running every day short after midnight doesn't work properly once per year after daylight-saving time adjustment. e.g. an expected logfile is missing ("somefile.YYYYMMDD.log") Discussion: The Unix date command calculates the wrong date when used with "--date yesterday" on the day after daylig...
Openbox Config File
I don't use desktop environments on Linux. I prefer small,fast, efficient window managers. Some years ago I used olvwm (open look window manager) which was dicontinued by sun. Then I switched to wmx which I patched for my needs, but still it was missing some features. Now I use openbox which is highly configureable ...