How to write Pg_agentt Back script for pg_backup.sh and pg_backup.config
Here are some scripts which will backup all databases in a cluster individually, optionally only backing up the schema for a set list. The reason one might wish to use this over pg_dumpall is that you may only wish to restore individual databases from a backup, whereas pg_dumpall dumps a plain SQL copy into a single file. This also provides the option of specifying which databases you only want the schema of. The idea is to run these in a nightly cron job.
- pg_backup.config - The main configuration file. This should be the only file which needs user modifications.
- pg_backup.sh - The normal backup script which will go through each database and save a gzipped and/or a custom format copy of the backup into a date-based directory.
- pg_backup_rotated.sh - The same as above except it will delete expired backups based on the configuration.
pg_backup.config
##############################
## POSTGRESQL BACKUP CONFIG ##
##############################
# Optional system user to run backups as. If the user the script is running as doesn't match this
# the script terminates. Leave blank to skip check.
BACKUP_USER=
# Optional hostname to adhere to pg_hba policies. Will default to "localhost" if none specified.
HOSTNAME=
# Optional username to connect to database as. Will default to "postgres" if none specified.
USERNAME=
# This dir will be created if it doesn't exist. This must be writable by the user the script is
# running as.
BACKUP_DIR=/home/backups/database/postgresql/
# List of strings to match against in database name, separated by space or comma, for which we only
# wish to keep a backup of the schema, not the data. Any database names which contain any of these
# values will be considered candidates. (e.g. "system_log" will match "dev_system_log_2010-01")
SCHEMA_ONLY_LIST=""
# Will produce a custom-format backup if set to "yes"
ENABLE_CUSTOM_BACKUPS=yes
# Will produce a gzipped plain-format backup if set to "yes"
ENABLE_PLAIN_BACKUPS=yes
# Will produce gzipped sql file containing the cluster globals, like users and passwords, if set to "yes"
ENABLE_GLOBALS_BACKUPS=yes
#### SETTINGS FOR ROTATED BACKUPS ####
# Which day to take the weekly backup from (1-7 = Monday-Sunday)
DAY_OF_WEEK_TO_KEEP=5
# Number of days to keep daily backups
DAYS_TO_KEEP=7
# How many weeks to keep weekly backups
WEEKS_TO_KEEP=5
######################################
pg_backup.sh
#!/bin/bash
###########################
####### LOAD CONFIG #######
###########################
while [ $# -gt 0 ]; do
case $1 in
-c)
if [ -r "$2" ]; then
source "$2"
shift 2
else
${ECHO} "Unreadable config file \"$2\"" 1>&2
exit 1
fi
;;
*)
${ECHO} "Unknown Option \"$1\"" 1>&2
exit 2
;;
esac
done
if [ $# = 0 ]; then
SCRIPTPATH=$(cd ${0%/*} && pwd -P)
source $SCRIPTPATH/pg_backup.config
fi;
###########################
#### PRE-BACKUP CHECKS ####
###########################
# Make sure we're running as the required backup user
if [ "$BACKUP_USER" != "" -a "$(id -un)" != "$BACKUP_USER" ]; then
echo "This script must be run as $BACKUP_USER. Exiting." 1>&2
exit 1;
fi;
###########################
### INITIALISE DEFAULTS ###
###########################
if [ ! $HOSTNAME ]; then
HOSTNAME="localhost"
fi;
if [ ! $USERNAME ]; then
USERNAME="postgres"
fi;
###########################
#### START THE BACKUPS ####
###########################
FINAL_BACKUP_DIR=$BACKUP_DIR"`date +\%Y-\%m-\%d`/"
echo "Making backup directory in $FINAL_BACKUP_DIR"
if ! mkdir -p $FINAL_BACKUP_DIR; then
echo "Cannot create backup directory in $FINAL_BACKUP_DIR. Go and fix it!" 1>&2
exit 1;
fi;
#######################
### GLOBALS BACKUPS ###
#######################
echo -e "\n\nPerforming globals backup"
echo -e "--------------------------------------------\n"
if [ $ENABLE_GLOBALS_BACKUPS = "yes" ]
then
echo "Globals backup"
if ! pg_dumpall -g -h "$HOSTNAME" -U "$USERNAME" | gzip > $FINAL_BACKUP_DIR"globals".sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to produce globals backup" 1>&2
else
mv $FINAL_BACKUP_DIR"globals".sql.gz.in_progress $FINAL_BACKUP_DIR"globals".sql.gz
fi
else
echo "None"
fi
###########################
### SCHEMA-ONLY BACKUPS ###
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
SCHEMA_ONLY_CLAUSE="$SCHEMA_ONLY_CLAUSE or datname ~ '$SCHEMA_ONLY_DB'"
done
SCHEMA_ONLY_QUERY="select datname from pg_database where false $SCHEMA_ONLY_CLAUSE order by datname;"
echo -e "\n\nPerforming schema-only backups"
echo -e "--------------------------------------------\n"
SCHEMA_ONLY_DB_LIST=`psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$SCHEMA_ONLY_QUERY" postgres`
echo -e "The following databases were matched for schema-only backup:\n${SCHEMA_ONLY_DB_LIST}\n"
for DATABASE in $SCHEMA_ONLY_DB_LIST
do
echo "Schema-only backup of $DATABASE"
if ! pg_dump -Fp -s -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to backup database schema of $DATABASE" 1>&2
else
mv $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz
fi
done
###########################
###### FULL BACKUPS #######
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
EXCLUDE_SCHEMA_ONLY_CLAUSE="$EXCLUDE_SCHEMA_ONLY_CLAUSE and datname !~ '$SCHEMA_ONLY_DB'"
done
FULL_BACKUP_QUERY="select datname from pg_database where not datistemplate and datallowconn $EXCLUDE_SCHEMA_ONLY_CLAUSE order by datname;"
echo -e "\n\nPerforming full backups"
echo -e "--------------------------------------------\n"
for DATABASE in `psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$FULL_BACKUP_QUERY" postgres`
do
if [ $ENABLE_PLAIN_BACKUPS = "yes" ]
then
echo "Plain backup of $DATABASE"
if ! pg_dump -Fp -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to produce plain backup database $DATABASE" 1>&2
else
mv $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE".sql.gz
fi
fi
if [ $ENABLE_CUSTOM_BACKUPS = "yes" ]
then
echo "Custom backup of $DATABASE"
if ! pg_dump -Fc -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" -f $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress; then
echo "[!!ERROR!!] Failed to produce custom backup database $DATABASE" 1>&2
else
mv $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress $FINAL_BACKUP_DIR"$DATABASE".custom
fi
fi
done
echo -e "\nAll database backups complete!"
pg_backup_rotated.sh
#!/bin/bash
###########################
####### LOAD CONFIG #######
###########################
while [ $# -gt 0 ]; do
case $1 in
-c)
CONFIG_FILE_PATH="$2"
shift 2
;;
*)
${ECHO} "Unknown Option \"$1\"" 1>&2
exit 2
;;
esac
done
if [ -z $CONFIG_FILE_PATH ] ; then
SCRIPTPATH=$(cd ${0%/*} && pwd -P)
CONFIG_FILE_PATH="${SCRIPTPATH}/pg_backup.config"
fi
if [ ! -r ${CONFIG_FILE_PATH} ] ; then
echo "Could not load config file from ${CONFIG_FILE_PATH}" 1>&2
exit 1
fi
source "${CONFIG_FILE_PATH}"
###########################
#### PRE-BACKUP CHECKS ####
###########################
# Make sure we're running as the required backup user
if [ "$BACKUP_USER" != "" -a "$(id -un)" != "$BACKUP_USER" ] ; then
echo "This script must be run as $BACKUP_USER. Exiting." 1>&2
exit 1
fi
###########################
### INITIALISE DEFAULTS ###
###########################
if [ ! $HOSTNAME ]; then
HOSTNAME="localhost"
fi;
if [ ! $USERNAME ]; then
USERNAME="postgres"
fi;
###########################
#### START THE BACKUPS ####
###########################
function perform_backups()
{
SUFFIX=$1
FINAL_BACKUP_DIR=$BACKUP_DIR"`date +\%Y-\%m-\%d`$SUFFIX/"
echo "Making backup directory in $FINAL_BACKUP_DIR"
if ! mkdir -p $FINAL_BACKUP_DIR; then
echo "Cannot create backup directory in $FINAL_BACKUP_DIR. Go and fix it!" 1>&2
exit 1;
fi;
#######################
### GLOBALS BACKUPS ###
#######################
echo -e "\n\nPerforming globals backup"
echo -e "--------------------------------------------\n"
if [ $ENABLE_GLOBALS_BACKUPS = "yes" ]
then
echo "Globals backup"
if ! pg_dumpall -g -h "$HOSTNAME" -U "$USERNAME" | gzip > $FINAL_BACKUP_DIR"globals".sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to produce globals backup" 1>&2
else
mv $FINAL_BACKUP_DIR"globals".sql.gz.in_progress $FINAL_BACKUP_DIR"globals".sql.gz
fi
else
echo "None"
fi
###########################
### SCHEMA-ONLY BACKUPS ###
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
SCHEMA_ONLY_CLAUSE="$SCHEMA_ONLY_CLAUSE or datname ~ '$SCHEMA_ONLY_DB'"
done
SCHEMA_ONLY_QUERY="select datname from pg_database where false $SCHEMA_ONLY_CLAUSE order by datname;"
echo -e "\n\nPerforming schema-only backups"
echo -e "--------------------------------------------\n"
SCHEMA_ONLY_DB_LIST=`psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$SCHEMA_ONLY_QUERY" postgres`
echo -e "The following databases were matched for schema-only backup:\n${SCHEMA_ONLY_DB_LIST}\n"
for DATABASE in $SCHEMA_ONLY_DB_LIST
do
echo "Schema-only backup of $DATABASE"
if ! pg_dump -Fp -s -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to backup database schema of $DATABASE" 1>&2
else
mv $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz
fi
done
###########################
###### FULL BACKUPS #######
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
EXCLUDE_SCHEMA_ONLY_CLAUSE="$EXCLUDE_SCHEMA_ONLY_CLAUSE and datname !~ '$SCHEMA_ONLY_DB'"
done
FULL_BACKUP_QUERY="select datname from pg_database where not datistemplate and datallowconn $EXCLUDE_SCHEMA_ONLY_CLAUSE order by datname;"
echo -e "\n\nPerforming full backups"
echo -e "--------------------------------------------\n"
for DATABASE in `psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$FULL_BACKUP_QUERY" postgres`
do
if [ $ENABLE_PLAIN_BACKUPS = "yes" ]
then
echo "Plain backup of $DATABASE"
if ! pg_dump -Fp -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress; then
echo "[!!ERROR!!] Failed to produce plain backup database $DATABASE" 1>&2
else
mv $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE".sql.gz
fi
fi
if [ $ENABLE_CUSTOM_BACKUPS = "yes" ]
then
echo "Custom backup of $DATABASE"
if ! pg_dump -Fc -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" -f $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress; then
echo "[!!ERROR!!] Failed to produce custom backup database $DATABASE"
else
mv $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress $FINAL_BACKUP_DIR"$DATABASE".custom
fi
fi
done
echo -e "\nAll database backups complete!"
}
# MONTHLY BACKUPS
DAY_OF_MONTH=`date +%d`
if [ $DAY_OF_MONTH -eq 1 ];
then
# Delete all expired monthly directories
find $BACKUP_DIR -maxdepth 1 -name "*-monthly" -exec rm -rf '{}' ';'
perform_backups "-monthly"
exit 0;
fi
# WEEKLY BACKUPS
DAY_OF_WEEK=`date +%u` #1-7 (Monday-Sunday)
EXPIRED_DAYS=`expr $((($WEEKS_TO_KEEP * 7) + 1))`
if [ $DAY_OF_WEEK = $DAY_OF_WEEK_TO_KEEP ];
then
# Delete all expired weekly directories
find $BACKUP_DIR -maxdepth 1 -mtime +$EXPIRED_DAYS -name "*-weekly" -exec rm -rf '{}' ';'
perform_backups "-weekly"
exit 0;
fi
# DAILY BACKUPS
# Delete daily backups 7 days old or more
find $BACKUP_DIR -maxdepth 1 -mtime +$DAYS_TO_KEEP -name "*-daily" -exec rm -rf '{}' ';'
perform_backups "-daily"
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