Linux: emergency reboot or shutdown
echo 1 > /proc/sys/kernel/sysrq
echo b > /proc/sysrq-trigger
Convert Virtualbox image to QEMU image:
qemu-img convert -f vdi -O qcow2 Virtualbox.vdi QEMU.qcow
Centos 7 change kernel:
awk -F\' /^menuentry/{print\$2} /etc/grub2.cfg
grub2-set-default 1
grub2-mkconfig -o /boot/grub2/grub.cfg
shutdown -r now
Mount RAMDISK:
mount -t tmpfs -o size=512m tmpfs /mnt/ramdisk
Create ansible role:
ansible-galaxy init <rollename>
Install LT kernel from Elrepo:
rpm -Uvh https://elrepo.org/linux/kernel/el7/x86_64/RPMS/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
yum --enablerepo=elrepo-kernel install kernel-lt
git - overwrite local files:
git fetch --all
git reset --hard origin/master