[WebServerMonitor] Couldn't get server version. Error retrieving IBM HTTP Server version in release 7.0.0.29 with APM PowerPack for Web Servers.

Products

• CA Application Performance Management Agent (APM / Wily / Introscope)
• INTROSCOPE

Issue/Introduction

Description:

When using APM PowerPack for WebServers, it obtains information about the webservers by making HTTP requests.

One important part of the process is obtaining the server version. This is done by reading a value published by the server in HTTP headers.

If the header value cannot be read, you will see this error message:

11/15/13 04:17:02 PM CET [INFO] [WebServerMonitor] Couldn't get server version http://100.100.100.100:8370/server-status

You will not see performance information for the webserver.

Solution:

IBM made changes to security beginning with IBM HTTP Server 7.0.0.29

Before that release, the default behavior was to publish the server header value, but since fixpack 29, the default is not to publish the server header.

This is documented here:

http://www-01.ibm.com/support/docview.wss?uid=swg1PM77980

To workaround this problem, add the value

AddServerHeader On

to httpd.conf .

Environment

Release:
Component: APMPPK