First off, I feel I should explain why it has taken so long to write Part 2. I had a bit of crash whilst mountain biking and fractured my right wrist which subsequently required two plates and ten screws to be inserted. Although still bandaged up, I’m officially back in the office, although my typing is somewhat slower. And yes, damn it… I am right handed!
Right, so what’s in Part 2? In Part 1 I stated what I would cover in Part 2 but as I have progressed I have had to change the content slightly to create a better flow. Here’s a summary of what I’m going to cover in this article:
- What are journal files (transaction journal files)?
- What the backup timer is and how to set it up.
- An explanation of the fields on System Backup Maintenance.
- Success and failure notifications.
- How do you know if a backup is in progress?
What are journal files?
In layman’s terms, when any record in a database is added, updated or deleted the operation (change to the data) is recorded in a file, this is known as a transaction journal file. For e.g. when a record is updated, a ‘before and after’ image of the record is recorded in the journal file so if for some reason the update cannot be completed then the database can be rolled back to the state before updating commenced.
The other very useful thing about journal files is they can be ‘played back’. For e.g. if I had a good database backup from 2 weeks ago and I had all the journal files since that backup, I would be able to apply all of the changes contained in the journal files to the backup, this is commonly referred to as restoring or recovering a database.
What is the backup timer and how to set it up.
Ah the infamous backup timer. Essentially, the backup timer causes a check to be performed on a regular frequency (usually every 10 minutes) to establish if the day and time has been reached for the Abel Database backup to be initiated. The activation of the backup timer is set up from the System Files Maintenance screen, but will need the Server background application to be running to perform a backup – see below. To activate the backup timer, select Database Backup from the Preset Timer combo box and click SAVE. You may wonder why the backup timer can be toggled on or off? The main reason is that some clients choose to have an Abel test environment running and generally this environment does not need to be backed up. Another is that some clients prefer to use the Jade Care tool set to manage their backups, hence not requiring this timer.
The Abel backup routines come as part of the Server background application which, as long as it has been enabled, will automatically start when the Abel server node [mode?] is started. When the Server background application is started, the backup timer is started.
An explanation of the fields on System Backup Maintenance.
The main purposes of the System Backup Maintenance screen are:
- To schedule the backup process (which days of the week and at what time).
- To set where the database backup files are stored.
- To set where the journal backup files are stored.
- To set up success and failure notifications.
Some of the fields are pretty self explanatory like which days of the week and at what time the backup is to run and where the backup files are stored. However there are a few fields that may not be as obvious such as:
- Journals Backup Folder: It’s important to understand this. When a journal switch occurs (a new journal file is started) the old journal file is copied to this location. With that in mind, we recommend that this folder be on a different physical disk to the Journals Root Folder. I’ll go into this in more detail in Part 3.
- Delete Journal files older than [X] days: This is a house keeping setting for deleting old journal files that are no longer of use. When closed journal files (in the Journals Root Folder and in the Journals Backup Folder) have been backed up to tape or a device they may be discarded.
- Journal File Size: This specifies the size of the transaction journal file. A journal switch occurs when the journal exceeds this size.
- Delete Backup History older than: The table on this screen lists all the backup jobs that have occurred. Every now and then you may wish to flush some or all of this history. To do this, enter the desired date and then click the Delete button to the right of the date field – doing this will delete all history older than the date entered.
- Server Background Running: This is an information only field. It tells you whether the Server Background Application is running or not. Unless there’s a very specific reason, it should always display Yes. If it says No and you are unaware of why then you’d better contact your Abel Distributor because the Abel backup relies on it running.
Success and Failure Notifications
Abel goes to a lot of trouble to tell you about problems with your backup should one occur, but the backup notification system needs to be setup in order for notifications to occur. There is a section for setting up notifications on the System Backup Maintenance screen. Notifications can be setup for reporting both a successful or failed backup. Abel offers two forms of notifications:
- Email notifications (up to two email addresses).
- Internal message notifications (up to two internal users)
Additionally, Abel has other internal checks to make sure the Abel backup system is healthy, such as:
- If a backup has been missed, a notification is sent out reporting which backups have been missed.
- If the backup timer is not configured correctly a notification is sent out reporting this. A common situation where this occurs is if the Abel database is moved to a different folder location or server, in this case Abel automatically disables the backup timer and so requires a user to reactivate it. The reason we disable it is most clients who have a test system will occasionally take a copy of their production database to replace their test database, and we don’t want the test system backing up over the top of the production system backup.
How do you know if a backup is in progress?
The System Backup Maintenance screen displays real time information about a backup that is in progress. The top entry in the history table will display information about the backup that is in progress. The status of the backup and which file is currently getting backed up are displayed. If the backup completes successfully without any errors the Status column will display Backup Completed. If the backup fails for any reason the status of the backup will display Failed and information about the error is displayed in the error column.
Hopefully after reading this you will have gained a better understanding of the Abel backup process and how to check your own setup.
Again your feedback is welcome so do post a comment if you have any questions.
In Part 3 I will cover how the journal file location can affect performance.