Linux, programming and more
Watchdog is responsible for monitoring tiny systems like raspberry PI, BeagleBone or any other system.
The main functionality of the watchdog is to check, if the system is still responding, lets say, to keep-alive messages.
Let’s assume, the system is stuck in a kernel panic, this will be automatically restarted by watchdog after reaching a grace time period. So a manual rebooting by unplugging the DC adapter is not required at all.
If you need to change the hostname of an existing munin node with a lot of data, and you want to retain all this existing historical data, follow this procedure:
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After some days of my vacation, my Fedora workstation was not able to boot. I stuck in the grub rescue shell, something was wrong with my MBR-recoord. There was a wrong UUID.
As I tried to update grub (command update-grub) – I stuck again – command not found! This is a Debian/Ubuntu specific command and is not available here.
This is a update-grub in Fedora way:
1 | grub2-mkconfig -o /boot/grub2/grub.cfg |
And finally the MBR installation:
1 | grub2-install --recheck --no-floppy /dev/sda |
Inetd listens for connections on certain sockets. When a connection is found on one of its sockets, it decides what service the socket corresponds to, and invokes a program to service the request. The server program is invoked with the service socket as its standard input, output and error descriptors.
Essentially, inetd allows running one daemon to invoke several others [Read more…]
If you get a certificate from a customer and you should implement it in some piece of software (for example nginx). The first step is to compare the received files.
After this check the displayed hash should [Read more…]