WriteBackExtreme keeps track of errors in log files. These log files can be viewed in the management console and are also visible in the file storage on the machine.
In the management console, Click on Info & License in the menu and click the pink System logs button. At the left there is a list of log files. The left part of the page shows the lines in the log files. Clicking on a line will open the details of the log item. There is also a download logs button that will compress all log files into a zip file for easy sending.
On the filesystem in the directory where WriteBackExtreme.exe is located, there is a directory .app-runtime/storage/logs which contains all log files. (On linux this will be at /usr/local/share/writebackextreme/.wbe-runtime/storage/logs)
When you encounter an error in the application, it is always helpful to send the logs with the support ticket so we can directly start investigating.
Application startup
When the application does not start, the cause can probably be found in the log files. they are located in <installation_path>/.wbe-runtime/storage/logs/*.log. When opening a support ticket, please provide these files.
Could not startup server, Contact Apps For Tableau support when the problem persists
The app server is unable to start. This can have multiple causes like:
Application is configured as administrator but is currently not running with administrator privileges.
Check if there is no other WriteBackExtreme process running in the background. Open Task manager and select the Details tab. You should have only one process called WriteBackExtreme.
Check if there is no other process running on the port that is configured in WriteBackExtreme. You can do that with this command in cmd:
netstat -aon
Open power shell and navigate to the directory where WriteBackExtreme.exe is located. run this command to manually trigger the application server:
./WriteBackExtreme.exe serve
This command might give more details about what went wrong.
listen tcp :443: bind: Only one usage of each socket address (protocol/network address/port) is hormally permitted
When this error appears in your wbe-application.log it is not able to spin the server because the port you have configured is already in use by another program.
WriteBackExtreme is slow or unresponsive
A typical reason of a slow experience is the database connection itself. Especially databases that are not running in the same network could potentially be slower.
When the management console for example is also slow you can take a look at the application performance. Open Powershell and navigate to the directory where WriteBackExtreme.exe is located. Run this command to see the statistics of the internal workers:
./WriteBackExtreme.exe workers --interactive
This will generate an interactive statistics table like so:
Note: The amount of rows (workers) is dependent on the amount of CUP's you have
When this shows a lot of Memory or CPU consumption it could be a good idea to increase the number of workers. Alter the wbe.config.yaml configuration file and add a num_workers option to the http part like so:
Note: Indentation in the wbe.config.yaml file matters! Always use 2 spaces indentation.
Increasing the amount of workers to more than 30 will not increase performance, it can lead to unwanted behavior.
WriteBackExtreme does not start after reboot when running as a service
A common cause of this is that when the repository database is mysql, postgresql or sql server on the same machine it could be that WriteBackExtreme is started before the database is started. This can be resolved by adding a delayed start in the service configuration.
Linux
Add a sleep to the service file (typically located at /etc/systemd/system/WriteBackExtreme.service)
ExecStartPre=/bin/sleep 15
Windows
Open services.
Look for WriteBackExtreme service
Right click and select properties
On the general tab, select Automatic (delayed start) as startup type.
Extension
The tableau Extension does not show any schemas
The main cause of this is that your user account does not have the correct permissions to view a schema. Check in the management console if this user belongs to any groups. Then check on the connections page if there are connections for any of the groups of this user. If that is the case, check if there are schemas attached to these connections. If there this is the case, go to the permissions tab of the schema and check if the groups this user belongs to has permissions enabled.
The tableau extension does not show (all) data
A cause of this could be Row level Security (RLS). RLS restricts the data shown base on policys set on the schema. Check in the management console if RLS is active.
Check in the management console in the Data tab if the data you are looking for is there. When RLS is active you can simulate what the extension should display by selecting the user.
Extension configuration can limit the data based on the `Show data when` setting.
Too many attempts
When the extension shows the message `Too many attempts` you have reached the limit of the built-in rate limiter. This rate limiter is limiting the network traffic per user to ensure the extension keeps it's stability.
When this error occurs there is probably too much data in the database table. The extension loads the data in chunks of 1000 rows, this means that a user can load a maximum of 60000 rows at a time.
There are ways to increase these limits but it comes with downsides in terms of reaching other limits like memory limits. The best way is to decrease your data.
If you do want to increase the pagination size, alter the wbe.config.yaml file in the WriteBackExtreme installation folder:
add a pagination_size in the db section:
Log states: Allowed memory size of xxx bytes exhausted
When this happens it simply tries to load too much data. The extension loads 1000 records at a time until all records are fetched. When you have loads of data within a row or a lot of columns it could exhaust the memory.
The best way to fix this is by limiting the data itself. Do you really need to fetch this much data? or could a slimmer table also do the job? Fact is that slimmer tables will perform a lot better than big tables that contain loads of data.
When a slimmer table is not an option, there are two options to fix this:
Decrease the number of loaded records at a time. (default 1000). Note that this will change the limit for all schemas!
Open the _settings table in your repository database and search for a row with the setting_key='db_pagination_size'. Change the setting_value to a value that works. You need to restart WriteBackExtreme for the changes to make effect
Increase the memory limit by altering the wbe.config.yaml file like so:
Note that the indentation in wbe.config.yaml matters!
WriteBackExtreme only supports data in UTF-8 Encoding. When your database table has characters other than UTF-8 this error message will be displayed.
This can only be solved by removing the non UTF-8 characters from your database table.
Single Sign On (SAML)
Authentication method by which the user authenticated with the service doesn't match requested authentication method
Whenever you suddenly get an error with Single Sign On related to the authentication method Password Protected does not match the .... with Microsoft please follow this link:
