How do I resolve an error when accessing the servers tab on recently upgraded/installed version 4.3?

[Preet.Gaur]

After a v4.3 upgrade, some users may need to resolve an error

AppDynamics v4.3 offers persistent view options for users using a POST request. Because some Java versions can't parse slashes ("/") in POST query parameters unless the "/" is defined in the config file, some users may see an error message.

This article includes the steps to edit the config file with a defined "/".

Table of Contents

• Problem
• Cause and Solution
• Additional Resoiurces

Problem

After upgrading or installing AppDynamics version 4.3.x, users may see the following error when accessing the "Servers" tab in the Controller UI.

The requested URL /controller/restui/userPreferenceManager/setGeneralUserPreference/SIMMachinesListController-stateId--SIM_MODE-4.3-metricToggles/[{"selected":false,"label":"Availability (%)","type":0,"metricName":"Hardware Resources|Machine|Availability"},{"selected":false,"label":"Availability (%) Trend","type":1,"metricName":"Hardware Resources|Machine|Availability"},{"selected":true,"label":"CPU (%)","type":0,"metricName":"Hardware Resources|CPU|%Busy"},{"selected":true,"label":"CPU (%) Trend","type":1,"metricName":"Hardware Resources|CPU|%Busy"},{"selected":false,"label":"CPU Steal (%)","type":0,"metricName":"Hardware Resources|CPU|%Stolen"},{"selected":false,"label":"CPU Steal (%) Trend","type":1,"metricName":"Hardware Resources|CPU|%Stolen"},{"selected":true,"label":"Disk I/O (%)","type":0,"metricName":"Hardware Resources|Disks|Avg IO Utilization (%)"},{"selected":true,"label":"Disk I/O (%) Trend","type":1,"metricName":"Hardware Resources|Disks|Avg IO Utilization (%)"},{"selected":true,"label":"Disk Usage (%)","type":0,"metricName":"Hardware Resources|Volumes|Used (%)"},{"selected":true,"label":"Disk Usage (%) Trend","type":1,"metricName":"Hardware Resources|Volumes|Used (%)"},{"selected":false,"label":"Load - 1min","type":0,"metricName":"Hardware Resources|Load|Last 1 minute"},{"selected":false,"label":"Load - 1min Trend","type":1,"metricName":"Hardware Resources|Load|Last 1 minute"},{"selected":true,"label":"Memory (%)","type":0,"metricName":"Hardware Resources|Memory|Used %"},{"selected":true,"label":"Memory (%) Trend","type":1,"metricName":"Hardware Resources|Memory|Used %"},{"selected":false,"label":"Memory Swap Used (%)","type":0,"metricName":"Hardware Resources|Memory|Swap Used %"},{"selected":false,"label":"Memory Swap Used (%) Trend","type":1,"metricName":"Hardware Resources|Memory|Swap Used %"},{"selected":true,"label":"Network I/O (%)","type":0,"metricName":"Hardware Resources|Network|Avg Utilization (%)"},{"selected":true,"label":"Network I/O (%) Trend","type":1,"metricName":"Hardware Resources|Network|Avg Utilization (%)"}] was not found on this server.

Following is a screenshot of the same error.

Cause and Solution

As of AppDynamics v4.3, view options are persistent for users. To do this, AppDynamics keeps track of the last tab a user selected on the time previous by using an API call.

The cause of the error is that some versions of Apache are unable to parse slashes ("/") in POST query parameters unless the "/"  is defined as query parameter in the config file.

Solution

The solution is to turn on the AllowEncodedSlashes NoDecode option in the Controller server's Apache config file (httpd.conf).

Additional Resources

For more information, see the Stack Overflow discussion Need to allow encoded slashes on Apache.