Application Server property settings for a Web server plug-in
Use this page to view or change appserver settings for a Web server plug-in.
To view this console page, click...
Application Servers | server | Additional Properties | Web server plug-in properties
- Server role
- Role this appserver is assigned.
Primary Add this appserver to the list of primary appservers. The plug-in initially attempts to route requests to the appservers on this list.
Backup Add the list of backup appservers. The plug-in does not load balance across the backup appservers. A backup server is only used if a primary server is not available. When the plug-in determines that a backup appserver is required, it goes through the list of backup servers, in order, until no servers are left in the list or until a request is successfully sent and a response received from one of the servers on this list.
Default setting: Primary
- Read/Write timeout
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Specify whether there is a time limit for how long the plug-in waits to send a request to or receive a response from the appserver.
If Set Timeout is selected, specify the length of time, in seconds that the plug-in waits to send a request or to receive a response.
It might take a couple of minutes for an appserver to process a request. Setting the value too low might cause the plug-in to send a false server error response to the client.
If you select No Timeout, the plug-in uses blocked I/O to write requests to and read responses from the appserver until the TCP connection times out.
This field is ignored for a plug-in running on a Solaris platform.
Data type Integer Default No Timeout - Connect timeout
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Specify whether or not there is a limited amount of time the appserver will maintain a connection with the Web server.
You can select either No timeout or Set timeout. If you select Set timeout you, must specify, in seconds, the length of time a connection with the Web server is to be maintained.
This property enables the plug-in to perform non-blocking connections with the appserver. Non-blocking connections are beneficial when the plug-in is unable to contact the destination to determine whether or not the port is available. If no value is specified for this property, the plug-in performs a blocking connect in which the plug-in sits until an operating system times out (which could be as long as 2 minutes depending on the platform) and allows the plug-in to mark the server unavailable.
A value of 0 causes the plug-in to perform a blocking connect. A value greater than 0 specifies the number of seconds you want the plug-in to wait for a successful connection. If a connection does not occur after that time interval, the plug-in marks the server unavailable and fails over to another appserver defined for the requested application.
Data type Integer Default 0 - Maximum number of connections that can be handled by the Application Server
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Maximum number of pending connections to an Application Server that can be flowing through a Web server process at any point in time.
This field corresponds to the ServerMaxConnections element in the plugin-cfg.xml file.
You can select either No limit or Set limit. If you select Set limit you, must specify the maximum number of connections that can exist between the Web server and the Application Server at any given point in time. For example, assuming that:
- The appserver is fronted by 5 nodes running an IHS Web server.
- Each node starts 2 processes.
- This property is set to 50.
In this example, the appserver could potentially get up to 500 connections. (You take the number of nodes, 5, multiply it by the number of processes, 2, and then multiply that number by the number specified for this property, 50, for a total of 500 connections.)
If this attribute is set to either zero or -1, there is no limit to the number of pending connections to the Application Servers.
Data type Integer Default -1 - The appserver is fronted by 5 nodes running an IHS Web server.
- Use extended handshake to check whether appserver is running
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When selected, the Web server plug-in will use an extended handshake to check whether or not the Application Server is running.
This field corresponds to the ServerExtendedHandshake element in the plugin-cfg.xml file.
Select this property if a proxy firewall is between the plug-in and the appserver.
The plug-in marks a server as down when the connect() fails. However, when a proxy firewall is in between the plug-in and the appserver, the connect() will succeed, even though the back end appserver is down. This causes the plug-in to not failover correctly to other appservers.
If the plug-in performs some handshaking with the appserver to ensure that it is started before it sends a request it can failover to another appserver if it detects that the appserver with which it is attempting to perform a handshake is down.
By default, this field is not checked. Select this field if you want to use extended handshake to check whether an appserver is running.
- Send the header "100 Continue" before sending the request content
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This field corresponds to the WaitForContinue element in the plugin-cfg.xml file.
When selected, the Web server plug-in will send the header "100 Continue" to the appserver before it sends the request content.
By default, this field is not checked. Select this field to enable this function.
Related tasks
Communicating with Web servers
Related Reference
Object names: What the name string cannot contain