Investigating problems with Web and Business tiers

The Web and Business tiers in the Application View provide a visual indication of problems with the performance and availability of application servers, compared to the set Minor and Critical thresholds. You can use the information presented on the Web and Business tiers (also known as presentation and logic tiers) to identify performance and availability problems in your application. The information presented by the tiers is based on monitoring data from the App Visibility agents.

The assignment of an application server as a Web or Business tier depends how App Visibility Manager recognizes most of the transactions on the server:

Web: A monitored server where most transactions are Transaction-type requests, that is, the server is the first to receive transaction requests within an application. For example, a web server that mostly receives end-user transaction requests, or a server that mostly receives requests from a non-monitored component (such as a PHP server), is recognized as a Web tier.
Business: A monitored server where most transactions are Request-type requests, that is, the server receives most requests from a monitored server.

For information about transaction types, see Analyzing business transactions.

This topic presents the following information about the application servers tiers:

Related topics

Setting up applications for monitoring

Analyzing end-user experience with the User tier

Analyzing database problems with the Database tier

Monitoring synthetic transactions by application

Before you begin

To see the Application View tab, your system must include TrueSight App Visibility Manager and you must have Application Operator Open link -level access, or higher.

Determine if the application has problems in the Web or Business tiers

In the Application View, the Web and Business tiers display the number of servers that have one or more transaction problems (latency violations or errors) during the selected period. The tiers display the following information:

Impacted Servers (number inside the circle). Number of impacted application servers
Colored part of the circle. Ratio of impacted application servers to the total number of servers. The color reflects whether the percentage of servers experiencing issues exceeds the defined thresholds.
Hits per second. Number of hits handled by the servers per second. The type of hit depends on the type of application server, for example, HTTP requests received by a web server, or messages received by a messaging server.

The following example describes the information in the Web and Business tiers:

Example of the Web and Business tiers

For the five-minute period reflected in the example, the Web tier shows that the combined hit rate of all the servers in the tier is one hit per second. The Business tier shows ten hits per second. Three web servers are impacted, that is, three servers have latency violations, errors, or server metric violations. Three servers is a little more than half of the number of web servers in the tier. One business server is impacted, representing half of the servers in the Business tier.

To select a Web or Business tier for analysis

On the Application View tab of the Application Monitoring page, position the time slider to select a five-minute period of interest.
Click the Web or Business tier to display the application servers that were active in the time period.

Example of the Tier Members and Selection Details
In the Tier Members section of the page, click a filter to show or hide application servers with the selected status.
Filters for servers with Critical and Minor events are selected by default to show the servers with detected issues.

Evaluating details of selected servers

Click one or more server names to examine problem details.

For selected servers, the following details are displayed:

Overall issues in the Summary tab
Examine specific problems with servers

Overall issues in the Summary tab

On the Summary tab, you can compare relative values for selected servers. For example, you might want to examine the server with the largest number of hits per second, or with the greatest percentage of latency violations.

For selected servers, the following details are displayed on the Summary tab, below the Tier Members section. Click a column heading to sort entries.

Column	Description
Action menu	Select Show Business Transactions to examine transaction details
Severity icon	Representation of the severity level of events on the server
Application Server Name	Name of the application server
Hits/Sec	Estimated number of requests sent to the servers per second Variations in the reported metrics might occur between the values in the tier box and the total of tier members because of the way fractional results are calculated.
Impacted Transactions	Percentage of transactions on the server with latency violations or errors that exceed defined thresholds
Latency Violations	Percentage of transactions on the server with latency violations
Errors	Percentage of transactions on the server with errors

The following example describes how the status is determined per transaction entry point, and how this can differ for the application or server status.

Example of server status and transaction status

In a five-minute period, a server has 25 transactions without any latency violations or availability errors, and 1 transaction entry point, login.jsp, that has an exception error.

The statuses of the application and server are Critical, even though fewer than 5% of all the transactions that were executed have issues. (That is, with the default settings of 5% for Minor, 10% for Critical.)

When you drill down to the login.jsp transaction, you see the status of the transaction is Critical because it ran once and had an exception error. That is, every time the transaction ran (once) it had an error, so the percentage of transaction executions with errors for this entry point is 100%.

Examine specific problems with servers

Click the Problems tab to examine the problems detected on the selected servers. Problems include latency violations, errors, and server metrics.

For selected servers, the following details are displayed. Click a column heading to sort entries.

Column	Description
Severity icon	Representation of the problem severity level The severity level remains unchanged until all transaction and server problems of that level are closed.
Problem	Brief description, such as `Transaction latency on the server` and `Transactions with error on the server`, or a brief description of a server metric problem (for example, `CPU usage`, `Memory usage`, and `Thread count`)
Application Server Name	Name of the application server
Problem Started	Time and date that the problem started which caused the displayed severity If the problem started earlier than the displayed time, click the start time to reset the time selection. The time slider moves to the five-minute period that includes the problem start time.
Threshold	For application server metrics, the value of the threshold that was crossed For transactions, which represent an aggregation of entry points, the threshold value is not applicable (N/A). For a list of default threshold values, see Application metrics and problems. To view the transaction thresholds, see Viewing event thresholds (SLAs) of applications.
Current Status	Open or Closed, which represents the current status of the problem, and time in which the problem was resolved, if applicable

Where to go from here

Analyzing business transactions