Unix Shell Script to backup the PostgreSQL database

posted Sep 17, 2010, 2:53 PM by Sachchida Ojha   [ updated Sep 17, 2010, 3:16 PM ]

#!/bin/sh
if [ "$(whoami)" != "postgres" ]; then
echo " only postgres user can run this Script"
exit
fi

#
# Postgresql backup script
#
# Version
# |
# -- 1.1.2
#
# Description
# |
# -- A bourne shell script that automates the backup, vacuum and
# analyze of databases running on a postgresql server.
#
#
# Requirements
# |
# -- grep, awk, sed, echo, gzip, chmod, touch, mkdir, date, psql,
# test, expr, dirname, find, tail, du, pg_dump, vacuum_db
#
# Installation
# |
# -- Set the path and shell you wish to use for this script on the
# | first line of this file. Keep in mind this script has only been
# | tested on the shells above in the "Tested on" section.
# |
# -- Set the configuration variables below in the configuration
# | section to appropriate values.
# |
# -- Remove the line at the end of the configuration section so that
# | the script will run.
# |
# -- Now save the script and perform the following command:
# |
# | chmod x ./pg_backup.sh
# |
# -- Now run the configuration test:
# |
# | ./pg_backup.sh configtest
# |
# | This will test the configuration details.
# |
# -- Once you have done that add similiar entries given as examples
# below to the crontab (`crontab -e`) without the the _first_ #
# characters.
#
# # Run a backup, vacuum and analyze every morning at 03:00
# 00 03 * * * /server/postgres/pg_backup.sh bva > /dev/null 2>&1
# # Run a backup at 09:00, 12:00, 15:00, 18:00 everyday
# 00 09 * * * /server/postgres/pg_backup.sh b > /dev/null 2>&1
# 00 12 * * * /server/postgres/pg_backup.sh b > /dev/null 2>&1
# 00 15 * * * /server/postgres/pg_backup.sh b > /dev/null 2>&1
# 00 18 * * * /server/postgres/pg_backup.sh b > /dev/null 2>&1
#
# Restoration
# |
# -- Restoration can be performed by using psql or pg_restore.
# | Here are two examples:
# |
# | a) If the backup is plain text:
# |
# | Firstly gunzip your backup file (if it was gzipped).
# |
# | gunzip backup_file.gz
# | psql -U postgres database < backup_file
# |
# | b) If the backup is not plain text:
# |
# | Firstly gunzip your backup file (if it was gzipped).
# |
# | gunzip backup_file
# | pg_restore -d database -F {c|t} backup_file
# |
# | Note: {c|t} is the format the database was backed up as.
# |
# | pg_restore -d database -F t backup_file_tar
# |
# -- Refer to the following url for more pg_restore help:
#
# http://www.postgresql.org/idocs/index.php?app-pgrestore.html
#
# To Do List
 # 1. db_connectivity() is BROKEN, if the script can not create a
# connection to postmaster it should die and write to the logfile
 # that it could not connect.
# 2. make configtest check for every required binary
 #
########################################################################
# Start configuration #
########################################################################
#
##################
# Authentication #
##################
#
# Postgresql username to perform backups under.
postgresql_username="postgres"
# Postgresql password for the Postgresql username (if required).
postgresql_password="password"
# Postgresql hostname to connect to.
postgresql_hostname="localhost"
##################
# Locations #
##################
#
# Location to place backups.
location_backup_dir="/var/lib/pgsql/data/backup"
# Location to place the pg_backup.sh logfile.
location_logfile="/var/lib/pgsql/data/backup/dump.log"
# Location of the psql binaries.
location_binaries="/usr/bin"
##################
# Permissions #
##################
#
# Permissions for the backup location.
permissions_backup_dir="0755"
# Permissions for the backup files.
permissions_backup_file="0644"
# Permissions for the backup logfile.
permissions_backup_log="0644"
##################
# Other options #
##################
#
# Databases to exclude from the backup process (separated by a space)
exclusions="template"
# Backup format
# |
# -- p = plain text : psql database < backup_file
# -- t = tar : pg_restore -F t -d database backup_file
# -- c = custom : pg_restore -F c -d database backup_file
#
backup_format="c"
# Backup large objects
backup_large_objects="yes"
# Gzip the backups
backup_gzip="yes"
# Date format for the backup
# |
# -- %d-%m-%Y = DD-MM-YYYY
# -- %Y-%m-%d = YYYY-MM-DD
# -- %A-%b-%Y = Tuesday-Sep-2001
# -- %A-%Y-%d-%m-%Y = Tuesday-2001-18-09-2001
# |
# -- For more date formats type:
#
# date --help
#
backup_date_format="%Y-%m-%d"
# You must comment out the line below before using this script
#echo "You must set all values in the configuration section in this file then run ./pg_backup.sh configtest before using this script" && exit 1
########################################################################
# End configuration #
########################################################################
#
#################
# Variables #
#################
#
version="1.1.2"
current_time=`date %H:%M`
date_info=`date $backup_date_format`
PGUSER="$postgresql_username"
PGPASSWORD="$postgresql_password"
PATH="$PATH:/bin:/usr/bin"
# Export the variables
export PGUSER PGPASSWORD PATH
#################
# Checking #
#################
#
# Check the backup format
if [ "$backup_format" = "p" ]; then
backup_type="Plain text SQL"
backup_args="-F $backup_format"
elif [ "$backup_format" = "t" ]; then
backup_type="Tar"
if [ "$backup_large_objects" = "yes" ]; then
backup_args="-b -F $backup_format"
else
backup_args="-F $backup_format"
fi
elif [ "$backup_format" = "c" ]; then
backup_type="Custom"
if [ "$backup_large_objects" = "yes" ]; then
backup_args="-b -F $backup_format"
else
backup_args="-F $backup_format"
fi
else
backup_format="c"
backup_args="-F $backup_format"
backup_type="Custom"
fi
#################
# Functions #
#################
#
# Obtain a list of available databases with reference to the user
# defined exclusions
db_connectivity() {
tmp=`echo -n '(';echo -n $exclusions | sed 's/\ /\|/g'; echo -n ')'`
if [ "$exclusions" = "" ]; then
databases=`$location_binaries/psql -h $postgresql_hostname -U $postgresql_username -q -c "\l" template1 | sed -n 4,/\eof/p | grep -v rows\) | awk {'print $1'} || echo "Database connection could not be established at $timeinfo" >> $location_logfile`
else
databases=`$location_binaries/psql -h $postgresql_hostname -U $postgresql_username -q -c "\l" template1 | sed -n 4,/\eof/p | grep -v rows\) | grep -Ev $tmp | awk {'print $1'} || echo "Database connection could not be established at $timeinfo" >> $location_logfile`
fi
}
# Setup the permissions according to the Permissions section
set_permissions() {
# Make the backup directories and secure them.
mkdir -m $permissions_backup_dir -p "$location_backup_dir/`date %B-%Y`/$date_info"
# Touch the log file
touch "$location_logfile"
 # Make the backup tree
chmod -f $permissions_backup_log "$location_logfile"
chmod -f $permissions_backup_dir "$location_backup_dir"
chmod -f $permissions_backup_dir "$location_backup_dir/`date %B-%Y`"
chmod -f $permissions_backup_dir "$location_backup_dir/`date %B-%Y`/$date_info"
}

# Run backup
run_b() {
for i in $databases; do
start_time=`date ' %s'`
timeinfo=`date ' %T %x'`
"$location_binaries/pg_dump" $backup_args -h $postgresql_hostname $i > "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
if [ "$backup_gzip" = "yes" ]; then
gzip "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup.gz"
else
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
fi

finish_time=`date ' %s'`
duration=`expr $finish_time - $start_time`
echo "Backup complete (duration $duration seconds) at $timeinfo for schedule $current_time on database: $i, format: $backup_type" >> $location_logfile
echo "Backup file name:"$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup
done
exit 1
}

# Run backup and vacuum
run_bv() {
for i in $databases; do
start_time=`date ' %s'`
timeinfo=`date ' %T %x'`
"$location_binaries/vacuumdb" -h $postgresql_hostname -U $postgresql_username $i >/dev/null 2>&1
"$location_binaries/pg_dump" $backup_args -h $postgresql_hostname $i > "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
if [ "$backup_gzip" = "yes" ]; then
gzip "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup.gz"
else
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
fi
finish_time=`date ' %s'`
duration=`expr $finish_time - $start_time`
echo "Backup and Vacuum complete (duration $duration seconds) at $timeinfo for schedule $current_time on database: $i, format: $backup_type" >> $location_logfile
done
exit 1
}

# Run backup, vacuum and analyze
run_bva() {
for i in $databases; do
start_time=`date ' %s'`
timeinfo=`date ' %T %x'`
"$location_binaries/vacuumdb" -z -h $postgresql_hostname -U $postgresql_username $i >/dev/null 2>&1
"$location_binaries/pg_dump" $backup_args -h $postgresql_hostname $i > "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
if [ "$backup_gzip" = "yes" ]; then
gzip "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup.gz"
else
chmod $permissions_backup_file "$location_backup_dir/`date %B-%Y`/$date_info/$current_time-postgresql_database-$i-backup"
fi
finish_time=`date ' %s'`
duration=`expr $finish_time - $start_time`
echo "Backup, Vacuum and Analyze complete (duration $duration seconds) at $timeinfo for schedule $current_time on database: $i, format: $backup_type" >> $location_logfile
done
exit 1
}

# Run vacuum
run_v() {
for i in $databases; do
start_time=`date ' %s'`
timeinfo=`date ' %T %x'`
"$location_binaries/vacuumdb" -h $postgresql_hostname -U $postgresql_username $i >/dev/null 2>&1
finish_time=`date ' %s'`
duration=`expr $finish_time - $start_time`
echo "Vacuum complete (duration $duration seconds) at $timeinfo for schedule $current_time on database: $i " >> $location_logfile
done
exit 1
}

# Run vacuum and analyze
run_va() {
for i in $databases; do
start_time=`date ' %s'`
timeinfo=`date ' %T %x'`
"$location_binaries/vacuumdb" -z -h $postgresql_hostname -U $postgresql_username $i >/dev/null 2>&1
finish_time=`date ' %s'`
duration=`expr $finish_time - $start_time`
echo "Vacuum and Analyze complete (duration $duration seconds) at $timeinfo for schedule $current_time on database: $i " >> $location_logfile
done
exit 1
}
# Print information regarding available backups
print_info() {
echo "Postgresql backup script version $version"
echo ""
echo "Available backups:"
echo ""
if [ ! -d $location_backup_dir ] ; then
echo "There are currently no available backups"
echo ""
exit 0
else
for i in `find "$location_backup_dir" -type d -maxdepth 2`; do
echo "$i `du -h \"$i\" | tail -n 1 | awk {'print $1'}`"
#for j in `ls "$location_backup_dir/$i"`; do
# echo " $j `du -h \"$location_backup_dir/$i/$j\" | tail -n 1 | awk {'print $1'}`"
#done
done
echo ""
fi
exit 1
}

 # Print configuration test
print_configtest() {
echo "Postgresql backup script version $version"
echo ""
echo "Configuration test..."
echo ""
# Check database connectivity information
echo -n "Database hostname : "
echo "$postgresql_hostname"
echo -n "Database username : "
echo "$postgresql_username"
echo -n "Database connectivity : "
$location_binaries/psql -h $postgresql_hostname -U $postgresql_username -q -c "select now()" template1 > /dev/null 2>&1 && echo "Yes" || echo "Connection could not be established..."

# Backup information
echo ""
echo "Backup information:"
echo ""
echo -n "Backup format : "
if [ "$backup_format" = "p" ]; then
echo "Plain text SQL"
elif [ "$backup_format" = "t" ]; then
echo "Tar"
else
echo "Custom"
fi
echo -n "Backup large objects : "
if [ "$backup_large_objects" = "yes" ]; then
echo "Yes"
else
echo "No"
fi
echo -n "Gzip backups : "
if [ "$backup_gzip" = "yes" ]; then
echo "Yes"
else
echo "No"
fi
echo -n "Backup date format : $date_info"
echo ""
# File locations
echo -n "Backup directory : "
echo "$location_backup_dir"
echo -n "Backup logfile : "
echo "$location_logfile"
echo -n "Postgresql binaries : "
echo "$location_binaries"
# Backup file permissions
echo -n "Backup directory permissions : "
echo "$permissions_backup_dir"
echo -n "Backup file permissions : "
echo "$permissions_backup_file"
echo -n "Backup log permissions : "
echo "$permissions_backup_log"
# Databases that will be backed up
echo -n "Databases that will be backed up : "
echo ""
for i in $databases; do
echo " $i"
done
# Databases that will not be backed up
echo -n "Databases that will not be backed up :"
echo ""
if [ "$exclusions" = "" ]; then
echo " none"
else
for i in $exclusions; do
echo " $i"
done
echo ""
fi

# Check if the backups location is writable
echo "Checking permissions:"
echo ""
echo -n "Write access : $location_backup_dir: "
# Needed to create/write to the dump location"
test -w "$location_backup_dir" && echo "Yes" || echo "No"
# Check if the logfile location is writable
echo -n "Write access : $location_logfile: "
# Needed to create/write to this scripts logfile"
if [ ! -x $location_logfile ] ; then
test -w `dirname "$location_logfile"` && echo "Yes" || echo "No"
else
test -w "$location_logfile" && echo "Yes" || echo "No"
fi

# Check if the binaries are executable
echo -n "Execute access : $location_binaries/psql: "
test -x $location_binaries/psql && echo "Yes" || echo "No"
echo -n "Execute access : $location_binaries/pg_dump: "
test -x $location_binaries/pg_dump && echo "Yes" || echo "No"
echo -n "Execute access : $location_binaries/vacuumdb: "
test -x $location_binaries/vacuumdb && echo "Yes" || echo "No"
echo ""
exit 1
}

 

# Print help
print_help() {
echo "Postgresql backup script version $version"
echo ""
echo "Usage: $0 [options]"
echo ""
echo "Options:"
echo " b, Backup ALL databases"
echo " bv, Backup and Vacuum ALL databases"
echo " bva, Backup, Vacuum and Analyze ALL databases"
echo " v, Vacuum ALL databases"
echo " va, Vacuum and Analyze ALL databases"
echo " info, Information regarding all available backups"
echo " configtest, Configuration test"
echo " help, This message"
echo ""
echo "Report bugs to <support@dbceo.com >."
exit 1
}
case "$1" in
# Run backup
b)
db_connectivity
set_permissions
run_b
exit 1
;;
# Run backup and vacuum
bv)
db_connectivity
set_permissions
run_bv
exit 1
;;
# Run backup, vacuum and analyze
bva)
db_connectivity
set_permissions
run_bva
exit 1
;;
# Run vacuum
v)
db_connectivity
set_permissions
run_v
exit 1
;;
# Run vacuum and analyze
va)
db_connectivity
set_permissions
run_va
exit 1
;;
# Print info
info)
set_permissions
print_info
exit 1
;;
# Print configtest
configtest)
db_connectivity
set_permissions
print_configtest
exit 1
;;
# Default
*)
print_help
exit 1
;;
esac
Comments