PQ74545: PLUGIN MARKS THE ONLY APPSERVER DOWN | |||||||||||||||||||||||||||||||||||||||||
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![]() APAR status Closed as program error. Error description In a plugin trace can be seen this error message: "ERROR: ws_server: serverSetFailoverStatus: Marking AppServer down". Next 60 seconds in a case that RetryInterval of ServerGroup is not set, all subsequent http requests to appServer fail. This problem is highly visible with thread based WebServer, such as iPlanet or IHS/Apache on Windows. Desired behaviour would be to have a configurable parameter in plugin config file. The customer should have a choice to decide, if they want the plugin to mark the only application server down in a simple WebSphere environment without server groups & clones, or to mark down the only AppServer that is up in a cloning WebSpheer environment. Please, take into consideration also a technote: "How to configure a weighted load balancing mechanism for the WebSphere plugin" that was written by Sharon McCloskey.Local fix Set RetryInterval of ServerGroup to some low value, such as 5 or 10 seconds. It might influence performance (but I am not sure how much).Problem summary **************************************************************** * USERS AFFECTED: WebSphere Application Server plugin users * **************************************************************** * PROBLEM DESCRIPTION: Only server in ServerGroup marked down. * **************************************************************** * RECOMMENDATION: * **************************************************************** In versions prior to 4.0, the failover code would not mark down the only server in a server group, as marking it down didn't really do anything useful: there's no failover if there's only one server in the ServerGroup, so marking the server down will at best make it take a little bit longer for the plugins to notice when the only application server comes back up. This APAR is to extend this behavior of not marking down the only server in a ServerGroup to WebSphere versions 4 and above.Problem conclusion This APAR pulls the behavior of 4.0 back into line with the older failover mechanism it was based on. Keep in mind that this fix only improves our behavior in cases where there is only one server in a ServerGroup, and is not meant as a fix for servers being marked down for unknown reasons. For any situation where a server is being marked down for unknown reasons, work still needs to be done to work out why the server is being marked down, even if applying this APAR makes the symptoms less severe - the kinds of things that cause servers to be marked down randomly are usually signs of a deeper problem that needs to be addressed.Temporary fix Comments
APAR is sysrouted FROM one or more of the following: PQ71608 APAR is sysrouted TO one or more of the following: Modules/Macros
Publications Referenced
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Product categories: Software > Application Servers >
Distributed Application & Web Servers > WebSphere Application
Server > General
Operating system(s):
Software version: 00W
Software edition:
Reference #: PQ74545
IBM Group: Software Group
Modified date: May 23, 2003
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