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(Created page with "=How to nuke linux machine remotely= ==chroot== telinit 2 for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices') ; do service...") |
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=How to nuke linux machine remotely= | =How to nuke linux machine remotely= | ||
==chroot== | ==chroot== | ||
lsblk | |||
telinit 2 | telinit 2 | ||
for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices') ; do service $SERVICE stop; done | for i in 1 2 3 4 5 ; do for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices|sudoscriptd') ; do service $SERVICE stop; done ; done | ||
service nfs stop | service nfs stop | ||
service rpcidmapd stop | service rpcidmapd stop | ||
| Line 20: | Line 21: | ||
chroot . | chroot . | ||
dd if=/dev/zero of=/dev/sda bs=1M & | dd if=/dev/zero of=/dev/sda bs=1M & | ||
while kill -USR1 $(pgrep -f dd); | while ps uxawww| grep -q "[d]d " ; do kill -USR1 $(pgrep -f "dd ") ; sleep 1 ; done | ||
If shutdown fail then this might work. | |||
echo 1 > /proc/sys/kernel/sysrq | |||
echo b > /proc/sysrq-trigger | |||
==pivot_root== | ==pivot_root== | ||
| Line 27: | Line 31: | ||
telinit 2 | telinit 2 | ||
# stop services | # stop services | ||
for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices') ; do service $SERVICE stop; done | for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices|sudoscriptd') ; do service $SERVICE stop; done | ||
service nfs stop | service nfs stop | ||
service rpcidmapd stop | service rpcidmapd stop | ||
| Line 42: | Line 46: | ||
cp -ax /usr/{bin,sbin,lib,lib64} /dev/shm/tmproot//usr/ | cp -ax /usr/{bin,sbin,lib,lib64} /dev/shm/tmproot//usr/ | ||
cp -ax /var/{account,empty,lib,local,lock,nis,opt,preserve,run,spool,tmp,yp} /dev/shm/tmproot//var/ | cp -ax /var/{account,empty,lib,local,lock,nis,opt,preserve,run,spool,tmp,yp} /dev/shm/tmproot//var/ | ||
rsync -aP /dev/ /dev/shm/tmproot/dev/ --exclude shm | |||
# Switch the filesystem root to the temporary filesystem: | # Switch the filesystem root to the temporary filesystem: | ||
Latest revision as of 10:30, 16 December 2019
How to nuke linux machine remotely
chroot
lsblk
telinit 2
for i in 1 2 3 4 5 ; do for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices|sudoscriptd') ; do service $SERVICE stop; done ; done
service nfs stop
service rpcidmapd stop
killall java
mkdir /dev/shm/ramdisk/
cd /dev/shm/ramdisk
mkdir proc sys dev usr
rsync -a /usr/bin/ usr/bin/
rsync -a /bin/ bin/
rsync -a /usr/sbin/ usr/sbin/
rsync -a /sbin/ sbin/
rsync -a /lib64/ lib64/
mount -t proc proc proc/
mount -t sysfs sys sys/
mount -o bind /dev dev/
mount /dev/shm -o remount,rw,exec,suid,dev
chroot .
dd if=/dev/zero of=/dev/sda bs=1M &
while ps uxawww| grep -q "[d]d " ; do kill -USR1 $(pgrep -f "dd ") ; sleep 1 ; done
If shutdown fail then this might work.
echo 1 > /proc/sys/kernel/sysrq echo b > /proc/sysrq-trigger
pivot_root
http://www.ivarch.com/blogs/oss/2007/01/resize-a-live-root-fs-a-howto.shtml
# Stop all services other than the network and SSH, and stop SELinux interfering:
telinit 2
# stop services
for SERVICE in $(chkconfig --list | grep 2:on | awk '{print $1}' | grep -Ev 'sshd|network|rawdevices|sudoscriptd') ; do service $SERVICE stop; done
service nfs stop
service rpcidmapd stop
setenforce 0
# Unmount all filesystems:
umount -a
# Create a temporary filesystem:
mkdir /dev/shm/tmproot/
mount none /dev/shm/tmproot/ -t tmpfs
mkdir /dev/shm/tmproot//{proc,sys,usr,var,oldroot}
cp -ax /{bin,etc,mnt,sbin,lib,lib64} /dev/shm/tmproot//
cp -ax /usr/{bin,sbin,lib,lib64} /dev/shm/tmproot//usr/
cp -ax /var/{account,empty,lib,local,lock,nis,opt,preserve,run,spool,tmp,yp} /dev/shm/tmproot//var/
rsync -aP /dev/ /dev/shm/tmproot/dev/ --exclude shm
# Switch the filesystem root to the temporary filesystem:
pivot_root /dev/shm/tmproot/ /dev/shm/tmproot/oldroot
mount none /proc -t proc
mount none /sys -t sysfs
mount none /dev/pts -t devpts
# restart sshd
service sshd restart
# You should now try to make a new connection. If that succeeds, close your old one to release the old pty device. If it fails, get the SSH daemon properly restarted before proceeding.
# Close everything that's still using the old filesystem:
umount /oldroot/proc
umount /oldroot/dev/pts
umount /oldroot/selinux
umount /oldroot/sys
umount /oldroot/var/lib/nfs/rpc_pipefs
# Now try to find other things that are still holding on to the old filesystem, particularly /dev:
fuser -vm /oldroot/dev
# Common processes that will need killing:
killall udevd
killall gconfd-2
killall mingetty
killall minilogd
Finally, you will need to re-execute init:
# telinit u
Unmount the old filesystem:
umount -l /oldroot/dev
umount /oldroot