Technical data

11 Configuring Network Resources
11-6 Creating and Configuring WebLogic Server Domains
Note: The default channel and administration channel, derived from values in the
ServerMBean and SSLMBean, are always considered for outgoing
connections, and use a default weight of 50.
Handling Channel Failures
Although WebLogic Server always attempts to use the highest-weighted channels
before lower-weighted ones, a network failure may render the selected channel
unavailable. To handle potential failures, WebLogic Server selects outgoing channels
using the following algorithm:
1. WebLogic Server first tries the highest-weighted channel having the required
quality of service.
2. If a connection cannot be made using the highest-weighted channel, WebLogic
Server tries the next-highest weighted channel with the required quality of
service.
3. If the connection request fails again, the server continues the connection attempt
using lower-weighted channels, until all channels have been attempted.
4. If the server cannot connect using any available channel, a failure message is
returned to the calling user.
This algorithm ensures that users receive a connection error message only when all
channels of the required quality of service level have been exhausted. If all channel
combinations are exhausted and another user attempts to initiate an outgoing
connection (or a connection is retried after a failure), WebLogic Server restarts the
channel selection process, starting with the highest-weighted channel.
Upgrading Quality of Service Levels for RMI
For RMI lookups only, WebLogic Server may upgrade the service level of an outgoing
connection. For example, if a T3 connection is required to perform an RMI lookup, but
an existing channel supports only T3S, the lookup is performed using the T3S channel.
This upgrade behavior does not apply to server requests that use URLs, since URLs
embed the protocol itself. For example, the server cannot send a URL request
beginning with
http:// over a channel that supports only https://.