Category: linux

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postsrsd monit config

This might work to configure monit on Debian (Jessie) to monitor postsrsd.

check process postsrsd matching "/usr/sbin/postsrsd"
    group postsrsd
    start program = "/etc/init.d/postsrsd start"
    stop  program = "/etc/init.d/postsrsd stop"
    if failed host localhost port 10001 then restart 
    if failed host localhost port 10002 then restart
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compiling a vanilla kernel to a .deb

As I keep losing this….

Creating a .deb kernel package from a vanilla kernel.org kernel :

  1. wget https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.4.24.tar.xz
  2. tar -xf linux-4.4.24.tar.xz
  3. cd linux-4.4.24
  4. cp /boot/config-whatever .config
  5. Optionally: edit and set: CONFIG_DEBUG_INFO=n to stop the *dbg* package being generated
  6. make olddefconfig
  7. make deb-pkg -j6 LOCALVERSION=-dg1
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Bash random number generation

Historically I’ve used $RANDOM as a random number source in bash — a bit like :

RAND=$(( $RANDOM % 10 ))

when I’ve needed a random number out of 0,1,2,3,4,5,6,7,8 and 9

one problem with this is that $RANDOM itself is populated between 0 and 32767 by the shell – so it’s not going to give totally even distribution.

Finally, I discovered ‘shuf’ — usage like :

shuf -i 1-100 -n 1

-i RangeFrom-RangeTo
-n how many

So –

RAND=$(( shuf -i 1-10 -n 1))