PostgreSQL WAL Files Settings

By default, Veeam Backup & Replication creates application-consistent image-level backups of VMs running the PostgreSQL instance and removes write ahead log (WAL) files after each successfully completed backup session, which allows you to restore PostgreSQL databases using specific backups. To protect mission-critical PostgreSQL databases, you can instruct Veeam Backup & Replication to create secondary restore points with WAL files in addition to primary image-level backups — this will allow you to restore your databases to specific points in time.

Configuring Access to PostgreSQL Instance

To specify how Veeam Backup & Replication will access the PostgreSQL instance, switch to the PostgreSQL tab of the Processing Settings window and do the following:

1. From the Specify PostgreSQL account with superuser privileges drop-down list, select a user account that Veeam Backup & Replication will use to connect to the PostgreSQL instance. The account must have privileges described in section Permissions. If you have not set up credentials beforehand, click the Manage accounts link or click Add on the right to add credentials.

By default, the Use guest credentials option is selected in the list. With this option selected, Veeam Backup & Replication will connect to the PostgreSQL instance under the account. In this case, Veeam Backup & Replication will use the account specified at the Guest Processing step of the wizard to access the VM guest OS and connect to the PostgreSQL instance.

Note that if you plan to select the System user without password file (peer) authentication method at the step 2 of this procedure, you can add a user account in the Credentials Manager without specifying the password for the account.

2. In the Specified user is section, specify how the user will authenticate against the PostgreSQL instance:

• Select Database user with password if the account you specified at the step 2 is a PostgreSQL account, and you entered the password for this account in the Credentials Manager.

• Select Database user with password file (.pgpass) if the password for the account you specified at the step 2 is defined in the .pgpass configuration file on the PostgreSQL VM. The password file must be located in the user's home directory. For more information about the password file, see PostgreSQL documentation.
• Select System user without password file (peer) if you want Veeam Backup & Replication to use the peer authentication method. In this case, Veeam Backup & Replication will use the account you specified at the step 2 as the OS account and as the PostgreSQL account to connect to PostgreSQL. For more information about the peer authentication method, see PostgreSQL documentation.

Configuring WAL Files Backups

To back up PostgreSQL WAL files periodically, do the following:

1. In the Backup logs every field, specify how frequently you want WAL files to be backed up. The maximum field value is 480 minutes.
2. In the Retain log backups section, choose either of the following options:

• Select the Until the corresponding image-level backup is deleted option if you want to remove WAL files backups and the related image-level backups at the same time, according to the retention policy settings specified at step 4.  
• Select the Keep only last <N> days of log backups if you want to retain WAL files backups for a specific time period, regardless of the retention policy settings specified for image-level backups. Note that WAL files backups must always be retained for a longer period than image-level backups.  

For more information on how Veeam Backup & Replication retains transaction logs, see the Veeam Backup & Replication User Guide, section Retention for PostgreSQL WAL Files.

3. In the Temporary location for archive logs section, specify the path to a folder on the PostgreSQL machine where Veeam Backup & Replication will temporarily store archive logs until they are backed up.

Keep in mind that you must create the folder beforehand manually. Also, make sure that there is enough free space in this folder for the log files and required permissions are granted to the user account.

4. In the Log shipping servers section, decide whether you want to use a specific Windows server to transfer WAL files backups or let Veeam Backup & Replication choose it automatically to reduce the load on the backup server.

By default, Veeam Backup & Replication automatically chooses a log shipping server for each of the processed VMs based on network settings and rules listed in the Veeam Backup & Replication User Guide, section Log Shipping Servers. You can also manually limit the list of machines that may be used as log shipping servers — to do that, click Choose, select the Use the specified servers only option and then select check boxes next to the necessary Windows servers.

For a Windows server to be displayed in the list of available guest interaction proxy servers, it must be added to the backup infrastructure as described in the Veeam Backup & Replication User Guide, section Adding Microsoft Windows Servers.