How to enable hibernation in Ubuntu 12.04 lts [Solved]

After upgrading to Precice Pangolin - Ubuntu 12.04 lts, I was unable to hibernate my machine by default. I googled it and found a solution(It worked for me.)

To check whether hibernate is supported, Open a terminal and type:

pm -hibernate

after entering this, your system will attempt a hibernate.

to enable hibernation, open a terminal and type the following line and press enter.

sudo gedit /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla

insert the following content

[Re-enable hibernate by default]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes

save and exit.

restart the system once and hibernation will be enabled. 

[Solved] Ubuntu Hibernate not working

For some laptop models, ubuntu installations show up by not hibernate in expected way. I have dug up in google about this issue and found some solutions.

this post.was the most relevant one thanks to the author,

make a script under /etc/pm/sleep.d/. 

sudo gedit /etc/pm/sleep.d/20_custom-ehci_hcd

paste the following code into the file you have just created:

#!/bin/sh
#inspired by http://art.ubuntuforums.org/showpost.php?p=9744970&postcount=19
#...and www.ubutnusolved.blogspot.com    


VERSION=1.1
DEV_LIST=/tmp/usb-dev-list
DRIVERS_DIR=/sys/bus/pci/drivers
DRIVERS="ehci xhci" # ehci_hcd, xhci_hcd
HEX="[[:xdigit:]]"
MAX_BIND_ATTEMPTS=2
BIND_WAIT=0.1

unbindDev() {
  echo -n > $DEV_LIST 2>/dev/null
  for driver in $DRIVERS; do
    DDIR=$DRIVERS_DIR/${driver}_hcd
    for dev in `ls $DDIR 2>/dev/null | egrep "^$HEX+:$HEX+:$HEX"`; do
      echo -n "$dev" > $DDIR/unbind
      echo "$driver $dev" >> $DEV_LIST
    done
  done
}

bindDev() {
  if [ -s $DEV_LIST ]; then
    while read driver dev; do
      DDIR=$DRIVERS_DIR/${driver}_hcd
      while [ $((MAX_BIND_ATTEMPTS)) -gt 0 ]; do
          echo -n "$dev" > $DDIR/bind
          if [ ! -L "$DDIR/$dev" ]; then
            sleep $BIND_WAIT
          else
            break
          fi
          MAX_BIND_ATTEMPTS=$((MAX_BIND_ATTEMPTS-1))
      done  
    done < $DEV_LIST
  fi
  rm $DEV_LIST 2>/dev/null
}

case "$1" in
  hibernate|suspend) unbindDev;;
  resume|thaw)       bindDev;;
esac

save the file and exit back to terminal.

Give execution permission:

sudo chmod 755 /etc/pm/sleep.d/20_custom-ehci_hcd


Now your system must work well with hibernate option.