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This section describes how to make a one-time backup and restore of the files and database. This is useful for rolling back to known-good versions of a service, such as at initial installation and just before an upgrade. First, you back up the database to a file within the file tree. Then, you back up the file tree. All of the information needed to rebuild the site, including the AOLserver config files, is then in tree for regular file system backup.
Back up the database to a file.
Download the backup script. Save the file export-oracle.txt as /tmp/export-oracle.txt
Login as root. The following commands will install the export script:
[joeuser ~]$ su - [root ~]# cp /tmp/export-oracle.txt /usr/sbin/export-oracle [root ~]# chmod 700 /usr/sbin/export-oracle
Setup the export directory; this is the directory where backups will be stored. We recommend the directory /ora8/m02/oracle-exports.
[root ~]# mkdir /ora8/m02/oracle-exports [root ~]# chown oracle:dba /ora8/m02/oracle-exports [root ~]# chmod 770 /ora8/m02/oracle-exports
Now edit /usr/sbin/export-oracle and change the SERVICE_NAME and DATABASE_PASSWORD fields to their correct values. If you want to use a directory other than /ora8/m02/oracle-exports, you also need to change the exportdir setting.
Test the export procedure by running the command:
[root ~]# /usr/sbin/export-oracle mv: /ora8/m02/oracle-exports/oraexport-service_name.dmp.gz: No such file or directory Export: Release 8.1.6.1.0 - Production on Sun Jun 11 18:07:45 2000 (c) Copyright 1999 Oracle Corporation. All rights reserved. Connected to: Oracle8i Enterprise Edition Release 8.1.6.1.0 - Production With the Partitioning option JServer Release 8.1.6.0.0 - Production Export done in US7ASCII character set and US7ASCII NCHAR character set . exporting pre-schema procedural objects and actions . exporting foreign function library names for user SERVICE_NAME . exporting object type definitions for user SERVICE_NAME About to export SERVICE_NAME's objects ... . exporting database links . exporting sequence numbers . exporting cluster definitions . about to export SERVICE_NAME's tables via Conventional Path ... . exporting synonyms . exporting views . exporting stored procedures . exporting operators . exporting referential integrity constraints . exporting triggers . exporting indextypes . exporting bitmap, functional and extensible indexes . exporting posttables actions . exporting snapshots . exporting snapshot logs . exporting job queues . exporting refresh groups and children . exporting dimensions . exporting post-schema procedural objects and actions . exporting statistics Export terminated successfully without warnings.
PostgreSQL. Create a backup file and verify that it was created and has a reasonable size (several megabytes).
[root root]# su - service0 [service0 service0]$ pg_dump -f /var/lib/aolserver/service0/database-backup/before_upgrade_to_4.6.dmp service0 [service0 service0]$ ls -al /var/lib/aolserver/service0/database-backup/before_upgrade_to_4.6.dmp -rw-rw-r-x 1 service0 service0 4005995 Feb 21 18:28 /var/lib/aolserver/service0/database-backup/before_upgrade_to_4.6.dmp [service0 service0]$ exit [root root]# su - service0 pg_dump -f /var/lib/aolserver/service0/database-backup/before_upgrade_to_4.6.dmp openacs-dev ls -al /var/lib/aolserver/service0/database-backup/before_upgrade_to_4.6.dmp exit
Back up the file system. Back up all of the files in the service, including the database backup file but excluding the auto-generated supervise directory, which is unneccesary and has complicated permissions.
In the tar command,
c create a new tar archive
p preserves permissions.
s preserves file sort order
z compresses the output with gzip.
The --exclude clauses skips some daemontools files that are owned by root and thus cannot be backed up by the service owner. These files are autogenerated and we don't break anything by omitting them.
The --file clause specifies the name of the output file to be generated; we manually add the correct extensions.
The last clause, /var/lib/aolserver/service0/, specifies the starting point for backup. Tar defaults to recursive backup.
[root root]# su - service0 [service0 service0]$ tar -cpsz --exclude /var/lib/aolserver/service0/etc/daemontools/supervise \ --file /tmp/service0-backup.tar.gz /var/lib/aolserver/service0/ tar: Removing leading `/' from member names [service0 service0]$
Suffer a catastrophic failure on your production system. (We'll simulate this step)
[root root]# svc -d /service/service0
[root root]# mv /var/lib/aolserver/service0/ /var/lib/aolserver/service0.lost
[root root]# rm /service/service0
rm: remove symbolic link `/service/service0'? y
[root root]# ps -auxw | grep service0
root 1496 0.0 0.0 1312 252 ? S 16:58 0:00 supervise service0
[root root]# kill 1496
[root root]# ps -auxw | grep service0
[root root]# su - postgres
[postgres pgsql]$ dropdb service0
DROP DATABASE
[postgres pgsql]$ dropuser service0
DROP USER
[postgres pgsql]$ exit
logout
[root root]#Restore the operating system and required software. You can do this with standard backup processes or by keeping copies of the install material (OS CDs, OpenACS tarball and supporting software) and repeating the install guide. Recreate the service user (service0).
Restore the OpenACS files and database backup file.
[root root]# su - service0 [service0 service0]$ cd /var/lib/aolserver [service0 aolserver]$ tar xzf /tmp/service0-backup.tar.gz [service0 aolserver]$ chmod -R 775 service0 [service0 aolserver]$ chown -R service0.web service0
Restore the database
Oracle.
Set up a clean Oracle database user and tablespace with the same names as the ones exported from (more information).
Invoke the import command
imp service0/service0 FILE=/var/lib/aolserver/service0/database-backup/nighty_backup.dmp FULL=YPostgres. If the database user does not already exist, create it.
[root root]# su - postgres
[postgres ~]$ createuser service0
Shall the new user be allowed to create databases? (y/n) y
Shall the new user be allowed to create more new users? (y/n) y
CREATE USER
[postgres ~]$ exit
Because of a bug in Postgres backup-recovery, database objects are not guaranteed to be created in the right order. In practice, running the OpenACS initialization script is always sufficient to create any out-of-order database objects. Next, restore the database from the dump file. The restoration will show some error messages at the beginning for objects that were pre-created from the OpenACS initialization script, which can be ignored.
[root root]# su - service0 [service0 ~]$ createdb service0 CREATE DATABASE [service0 ~]$ psql -f /var/lib/aolserver/service0/packages/acs-kernel/sql/postgresql/postgresql.sql service0 (many lines omitted) [service0 ~]$ psql service0 < /var/lib/aolserver/service0/database-backup/database-backup.dmp (many lines omitted) [service0 ~]$ exit [postgres ~]$ exit logout
Activate the service
[root root]# ln -s /var/lib/aolserver/service0/etc/daemontools /service/service0 [root root]# sleep 10 [root root]# svgroup web /service/service0