The following conditions have been verified:

• The Monitor database is configured correctly.
• There are no communication issues between Director and the Delivery Controller.
• There are no connectivity issues between the Delivery Controller and the SQL Server hosting the Monitor database.

A CDF trace captured on the Delivery Controller shows multiple exceptions similar to the following:

Failed to add VdaProcessData payload. Machine: S-1-5-21-XX, Exception System.Data.Entity.Infrastructure.DbUpdateException: An error occurred while updating the entries.
See the inner exception for details.
---> System.Data.Entity.Core.UpdateException: An error occurred while updating the entries. See the inner exception for details.
---> System.Data.SqlClient.SqlException: The transaction log for database 'MONITOR_DB' is full due to 'LOG_BACKUP'.
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)

This exception indicates that:

• The Citrix Monitor Service cannot write new monitoring data to the Monitor database.
• The SQL Server transaction log is full.

The SQL Server transaction log for the Monitor database is full. As a result, SQL Server rejects new write operations, including inserts performed by the Citrix Monitor Service (for example, VdaProcessData payloads).

This issue can occur for several reasons, including:

• The disk hosting the transaction log is full.
• The transaction log file has reached its configured maximum size.
• Transaction log autogrowth is disabled.
• Scheduled transaction log backups are failing or are not running (when the database uses the Full or Bulk-Logged recovery model).
• A long-running transaction or another condition is preventing transaction log truncation.

The database administrator (DBA) should investigate the Monitor database and ensure that sufficient transaction log space is available.

The following queries can help identify the cause of the issue.

Check the recovery model and determine why the transaction log cannot be reused:

SELECT name, recovery_model_desc, log_reuse_wait_desc FROM sys.databases WHERE name = 'MONITOR_DB';
*Replace MONITOR_DB with the name of your Monitor database.

Check transaction log usage:

SELECT * FROM sys.dm_db_log_space_usage;

Check the transaction log file location, size, autogrowth, and maximum size:

SELECT
    name,
    physical_name,
    size,
    size * 8 / 1024 AS SizeMB,
    max_size,
    growth
FROM sys.database_files;

The DBA should also verify:

• Available free disk space on the volume hosting the transaction log file.
• Available free space at the transaction log backup destination (if log backups are configured).
• Whether autogrowth is enabled.
• Whether the transaction log file has reached its configured maximum size.
• Whether scheduled transaction log backups are completing successfully.

Users might not see recent historical data in Citrix Director. This can affect the Dashboard, Trends, Filters, and Summary views.

XenDesktop Database Transaction Log Growing Excessively

Provisioning Services: PVS Servers May Stop Responding Or Target Devices May Freeze During Startup Due To Large Size Of MS SQL Transaction Logs