When to use AlwaysOn availability in SQL Server?
We are using AlwaysOn Availability Group feature of SQL Server 2012. Regular full database backups and transaction log backups are done every day on the secondary database. I have read here doing the transaction log backup on either the primary replica or the secondary replica will mark both replicas’ transaction logs as reusable.
Why is log file not shrinking in AlwaysOn group?
The problem is Redo Queue Size in Secondary-1 Node is increasing and not decreasing as what I through it should. Also log-file on Primary node is slowly increasing which is going to fill-up whole disk-space. Now Secondary-1 Node showing LOG-BACKUP. How do I solve this issue? Should I take Log backup on Secondary-1 Node and check?
Why is MY SQL server log file still full?
I am guessing since log_reuse_wait_desc is showing “AVAILABILITY_REPLICA” on Primary Node, means not all the log is transferred to Secondary replica, and so its still full. I checked Redo Queue Size in Secondary-1 Node showing 27GB, Secondary-2 is showing nothing. So most likely Secondary 1needs to get all logs from Primary.
How big is the SQL server log file?
Primary node, one secondary node in Sync mode and another secondary node in Async mode. Main Database on Primary node, log file-size is 434GB, Used 99.91%. Log backups is happening every hour only on Primary node.
What happens if your SQL server log file is too big?
SQL Server log file is too big – resolved! If your SQL Server transaction log (LDF) file is too big – you are doing something wrong. As technet puts it: Typically, truncation occurs automatically under the simple recovery model when database is backed up and under the full recovery model when the transaction log is backed up.
Why did transaction log grow to 121gb?
Determine why did the log grow to 121Gb so it does not repeat (you have a suspicion, would be nice to confirm if possible). Size the log to a size appropriate for your operational needs.
Why is the AlwaysOn availability group log file so big?
When you use AlwaysOn Availability Group, even if you take a proper backup the log file might grow larger and the log drive might get full over time. in order to maintain proper (minimize) log file size you can use the following technique. on the AlwaysOn configuration, change the backup priority options to primary replica/server.
Which is better synchronous commit mode or AlwaysOn?
Synchronous-commit mode emphasizes high availability over performance, at the cost of increased transaction latency. Under synchronous commit mode, transactions wait to send the transaction confirmation to the client until the secondary replica has hardened the log to disk.
How does a transaction log backup affect the log chain?
For example, if a transaction log backup is taken on an asynchronous replica that is significantly behind the primary replica, what will actually be backed up and how will that affect the log chain? In addition, since the log backups can be taken from either the primary replica or any secondary replica, how will the log chain be maintained?