Database administrators have to identify the problems at the first point as and when they happen to ensure smooth management of the database applications. When it comes to SQL server being used as the database, it is essential to know the troubleshooting steps and the tools which you can use. In this article, we are trying to cover the SQL server troubleshooting tips and the tools used to deal with SQL server problems.
When we are dealing with technical problems, it is essential to investigate and uncover the actual root cause of it. Regardless of the issue in hand, you need to do some in-depth analysis to understand what causes the problems and which elements to be isolated in order to control it. There are several such tools in order to look for clues in SQL server administration,
Tools for SQL troubleshooting
There are a huge number of tools used for SQL troubleshooting, which we may not be able to cover in full. So, here we will discuss the top tools which are unavailable within the SQL Server and also for Windows OS. In many cases, one shouldn't be able to find enough info by using these tools only to determine the actual cause of the problems, so it needs to be used in effective combinations with other strategies to delineate the actual trouble. Some of the top tools used are:
- Event viewer
When the SQL Server starts, it initiates a default trace event. The profiler can help to review this information which is captured through the default trace events. You may be amazed to see the options to find by exploring this default trace info. Adding to it, you can also find it very useful to create your own trace while doing troubleshooting of the problems.
It is the same Notepad we know by default, which may not seem to be ideal troubleshooting too. However, this can be used for opening various log files. A notepad will let you do the string search within the log files which are larger in size to find the needed information quickly. If the log files are very lengthy, then you may have to use WordPad as an alternative.
When your SQL system has any problems, then the event records will write such events to the event logs of Windows. You may browse through such events once in a while by using the tool Event Viewer. These entries in the event log will give you some quick solutions as to why the SQL Server instance doesn't behave properly given the fact that there are many even records associated with the problems you are working on.
Information gathering for SQL server troubleshooting
In order to understand a problem, you have to fist collection some relevant information about the problem. One should review the log files in order to understand what log records and errors messages are there, which may lead to better understand the causes of the problem. Here is a step-by-step approach to gathering information in terms of SQL server issues. Refer to RemoteDBA.com for more customized approaches.
The primary step in resolving a problem is to collect relevant facts. You should understand what kind of an issue is happening for which you should interview the DBAs, programmers, and even the customers if there is access. You have to analyze if it's a system-wide issue or limited around a localized application or any components of that application.
For this, you should also know the timeframe around the occurrence of an issue or whether it is a problem or not. Adding to it, you also should note when the last time system was working properly. You should also identify if there are any new systems or application changes got introduced, which might have ended up in any trouble. By having some real facts about the problem, you can search for any available clues which may lead to identifying the root cause of the issue.
Testing it in different machines and environment
You should run testing in various environments as a part of fact gathering. Sometimes, even seasoned technicians tend to miss out this strategy. Testing at different environments will help gather more information and also to have a better insight towards the issue.
Sometimes, you may find out only the environment gets affected, against a set of environments. If only one such environment gets affected, the problem might be some configuration errors related to that environment rather than the system. Sometimes, it may be the data captured in that environment might be causing the issue.
Similar to environments, you may also try testing for various machines also as well as application servers. You may sometimes find a different setup or configuration causing the issue. This way, you have to explore all various set-ups available and use the configuration options to document which all work and which won't.
Review SQL error logs
There is a log file maintained by the SQL Server as "ERRORLOG." Each time the server startups, a new error log file gets created. You can also find up to six old log files in the directory. There is a sequential number also associated with each file to understand its particulars. You can locate this ERRORLOG file at the "Log" folder in the standard "Program Files Microsoft SQL Server."
You can easily find the logs associated with the timeframe of the occurrence of the problem. You can also check an see if there any anomalies in the output messages by the SQL Server. Sometimes, if there is a change detected by the SQL Server or it encounters any issues, it gets logged to the ERRORLOG file.
At the next step, you can use the event viewer to look at various log records for warnings and actual errors events. An expert review of the default trace, which is the evidence that the SQL Server automatically starts to be done next. This trace will have details of all the configuration changes. You also have to check the changelog also to get some clues about why the specific problems in occurring and what application or modification is causing the problem. Once on reaching up to this level, the troubleshooting is much easier.