Troubleshoot SQL Server Agent jobs

SQL Server Agent is a Microsoft Windows service that executes scheduled administrative tasks, which are called jobs in SQL Server. Jobs can automate numerous tasks such as backing up a database, updating statistics, monitoring system jobs, and more. However, like any other service, it can face issues that disrupt normal operations. This article will delve into common problems that may arise in SQL Server Agent jobs and demonstrate solutions on how to troubleshoot them effectively.

Understanding the SQL Server Agent Job

SQL Server Agent jobs perform various tasks in an allocated schedule. But before debugging any error, it’s essential to understand the structure of these jobs. A SQL Server Agent job comprises one or more steps, a schedule, alerts, and notifications. Each step is necessary to complete the job, and they must all run successfully for the job to succeed.

Common Issues with SQL Server Agent Jobs

SQL Server Agent Job Failed to Run

This is amongst the most common issues with SQL Server Agent jobs. You may find this error in the job history. The usual suspects are:

• Incorrect Credentials: If the job owner does not have enough permissions to execute the necessary tasks, the job will fail.
• Disabled SQL Server Agent Service: Check if your service is running. If not, set it to “Automatic” and restart your server if necessary.

Job Failure Without Error Message

In some cases, the job fails without any error message. In such a case, you can update the job step command to output to a text file. By doing this, you get more information on what may have caused the job to fail.

For example:

sql
exec sp_mysproc > C:\outputs\output.txt

This will output the results of ‘sp_mysproc’ stored procedure to ‘output.txt’.

SQL Server Agent Not Starting

There are situations where the SQL Server Agent service fails to start. This might be due to issues with the MSDB database, lack of necessary permissions, or maybe, the service account has been deleted, disabled, or the password changed.

SQL Server Performance Affected by Runaway Jobs

There might be situations where long-running jobs can slow down the performance of your SQL Server. To pinpoint such jobs, you can use the ‘sys.dm_exec_requests’ dynamic management view, which will show you the currently running requests.

For example:

sql
SELECT session_id,
start_time,
status,
command,
database_id,
user_id,
wait_type,
wait_time,
cpu_time,
total_elapsed_time
FROM sys.dm_exec_requests

Troubleshooting SQL Server Agent Job Failures

1. Checking the Job History: The very first step is to check the job’s history in SQL Server Agent, which will show you if the job succeeded or failed and will provide a detailed error message if the job failed.
2. Checking Account Permissions: Verify if the SQL Server Agent service account has the necessary permissions to execute the job.
3. Checking Job Ownership: The job owner may not have the required permissions to execute the job. This can be solved by changing the job ownership in the ‘Owner’ box.
4. SQL Server Agent Log: Check the SQL Server Agent log as it might provide valuable information in troubleshooting the SQL Server job.

Conclusion

Understanding the roots of SQL Server Agent jobs and how they function is paramount. When they fail, it becomes an intimidating task to troubleshoot the issue, especially when the error messages are not clear. However, understanding the common issues and knowing how to decode the varied error notifications can make the task less daunting. Reading and interpreting SQL Server logs, checking job histories, verifying permissions and ownerships, and ensuring that services are up and running are fundamental troubleshooting tasks any database administrator should be familiar with.

No single troubleshooting method solves all SQL Server Agent jobs errors, but having a toolkit of solutions will save ample time and result in faster resolution times. SQL Server Agent jobs, while integral, can be a source of problems if not correctly managed. Learning how they operate and how to troubleshoot these issues is crucial in maintaining a healthy SQL Server environment.

Practice Test

True/False: You can view the history of a SQL Server agent job by using the default trace.

• True
• False

Answer: True

Explanation: The default trace in SQL Server provides information about when and how a job ran. You can view this information by accessing the traces.

True/False: SQL Server Management Studio (SSMS) can be used to troubleshoot SQL Server Agent jobs.

• True
• False

Answer: True

Explanation: SQL Server Management Studio (SSMS) has a feature that allows the user to check and view the job activity monitor, which provides information about the SQL Server Agent jobs.

Which of the following can be a source of SQL Server Agent job failure?

• Incorrect scripts
• User privileges issue
• Network connectivity issues
• None of the above

Answer: Incorrect scripts, User privileges issue, Network connectivity issues

Explanation: Any of these mentioned issues can become a source of SQL Server Agent job failure.

How can you determine the status of a SQL Server Agent job?

• Job Activity Monitor
• Error logs
• Both A and B
• None of the above

Answer: Both A and B

Explanation: You can determine the status of a SQL Server Agent job by monitoring job activity or analyzing error logs.

True/False: SQL Server Agent has built-in support for automatic retries after a failure.

• True
• False

Answer: True

Explanation: SQL Server Agent does support automatic retries after a job failure. The number and interval of retry attempts can be configured in job step properties.

True/False: SQL Server Agent requires the user privileges to be set up directly on the database.

• True
• False

Answer: False

Explanation: SQL Server Agent uses a service account, which can be configured with necessary privileges without setting it up directly on the database.

In which SQL Server system database are SQL Server Agent jobs stored?

• Master
• Model
• Msdb
• Tempdb

Answer: Msdb

Explanation: The msdb database stores SQL Server Agent information, including job details.

Which tool is used to create, modify, and delete SQL Server Agent jobs?

• SQL Server Configuration Manager
• SQL Server Job Manager
• SQL Server Management Studio
• SQL Server Agent

Answer: SQL Server Management Studio

Explanation: SQL Server Management Studio (SSMS) is used to manage SQL Server Agent jobs.

True/False: It is not possible to disable a SQL Agent job that is currently running.

• True
• False

Answer: False

Explanation: A SQL Agent job can be disabled even when it is running. However, this will not stop the execution of a currently running instance of the job.

What is the default retry interval for a job step in a SQL Server Agent job?

• 5 minutes
• 1 minute
• 0 minutes (No retry)
• 10 minutes

Answer: 0 minutes (No retry)

Explanation: By default, there is no retry interval set for a SQL Server Agent job. This means the job will not automatically retry in case of failure unless it is configured otherwise.

True/False: SQL Server Agent allows job chaining, i.e., executing one job upon the successful completion of another.

• True
• False

Answer: True

Explanation: SQL Server Agent supports job chaining. A job step can be configured to execute another job upon its success, failure, or completion.

True/False: Sysadmin role is automatically granted all permissions on SQL Server Agent.

• True
• False

Answer: True

Explanation: The sysadmin role is automatically granted all permissions on SQL Server Agent, allowing them to perform any action.

Which of the following commands can be used to start or stop SQL Server Agent service?

• sqlagent
• net start
• sqlserver
• net stop

Answer: net start, net stop

Explanation: The ‘net start’ and ‘net stop’ commands are used to start and stop respective services, including SQL Server Agent.

Which of the following SQL Server Agent system stored procedures can be used to create a job?

• sp_add_job
• sp_delete_job
• sp_update_job
• sp_create_job

Answer: sp_add_job

Explanation: The stored procedure used to create a new SQL Server Agent job is sp_add_job.

True/False: SQL Server Agent jobs are always running in the background.

• True
• False

Answer: False

Explanation: SQL Server Agent jobs are not always running. They run on scheduled times or when they are manually started.

Interview Questions

What is the first step when troubleshooting a failed SQL Server Agent job?

The first step is usually to check the job history. The job history can provide a detailed report about the job execution, including any error messages encountered.

What can you do if a SQL Server Agent job is taking longer to run than expected?

You can examine the job history and the SQL Server Error Log to identify if there are any errors or delays. Additionally, you can monitor the job’s progress and performance using SQL Server Performance Monitor and Activity Monitor.

How do you view the history of SQL Server Agent Jobs?

In SQL Server Management Studio, navigate to the SQL Server Agent, then Jobs. Right-click on the job you want to see the history for, and select ‘View History’.

If an SQL Server Agent Job occasionally fails with a network-related error, what could be the problem?

Intermittent network errors can be due to various issues like network congestion, network hardware failures, or issues with the network drivers. This can sometimes be resolved by retuning network settings or fixing the network hardware or drivers.

How can you find out who modified a SQL Server Agent Job?

This can be found in the system tables in the msdb database. The sysjobs table has a column called “date_modified” and “modified_by”.

What should you do if you receive an ‘access denied’ error when running a SQL Server Agent job?

The SQL Server Agent service account or the proxy account for the job step may lack the necessary permissions. Make sure these accounts have the rights to access required resources.

How can you verify if SQL Server Agent is running or not?

In SQL Server Management Studio, the SQL Server Agent node will display a green arrow if it is started or a red square if it is stopped.

What is steps can you take if a SQL Server Agent job is failing to complete?

To resolve this issue, you can troubleshoot following these steps: Understanding what the job does, viewing the job history for errors, checking the SQL Server error logs for details of the error, and making sure that the server has sufficient resources like CPU, Memory, Disk IO, etc.

How can you schedule SQL Server Agent Jobs to run at a specific time?

In the properties of the SQL Server Agent job, there is a Schedules page. Here you can create a new schedule by specifying the time and frequency at which the job should run.

What can cause a SQL Server Agent Job to skip scheduled runs?

A job may skip scheduled executions if the SQL Server Agent service isn’t running at the scheduled time, if the job is already running at the scheduled start time, or if the job is disabled.

How can you enable logging in SQL Server Agent jobs for better troubleshooting?

In the job step properties, under the Advanced page, you can specify a file under the ‘Output file’ section. All execution results, including errors, will be written to this file.

How do you delay the start of a SQL Server Agent job?

In the job step properties, under the General page, you can set the ‘Retry attempts’ and ‘Retry interval (minutes)’ options. This tells SQL Server Agent to automatically retry the job if it fails at first.

What role must the user have to be able to manage SQL Server Agent jobs?

To manage SQL Server Agent jobs, the user must be a member of one of the SQL Server Agent fixed database roles in the msdb database: SQLAgentUserRole, SQLAgentReaderRole, or SQLAgentOperatorRole.

How can you find out the last time a SQL Server Agent job was run?

This can be obtained from the job history. In SQL Server Management Studio, navigate to SQL Server Agent, then Jobs. Right-click on the job and select ‘View History’. The last run date is displayed there.

What should you do if an SQL Server Agent job is stuck in a running state?

You can try stopping the job manually using ‘Stop Job’ option in SQL Server Management Studio. Be careful as this might have impact on the current operations. If the problem persists, there might be an issue like a deadlock that needs to be investigated and resolved.