Handling weblogic T3 protocol message size issues

Do not be surprised when you see an error like below in weblogic server logs.

Incoming message of size: '10000080' bytes exceeds the configured maximum of: '10000000' bytes for protocol: 't3

In nutshell, above error happens when either weblogic server is not configured to handle message of size more than 10MB or client connected to WLS could not handle more than 10MB message size.
Most of the times it is JMS message processing but need not be always JMS.

First lets understand what is T3 and how it works.

T3 is a proprietary communication protocol being used by WLS to handle data traffic between java to java applications or JVM to JVM
WLS has a mechanism to keep track of JVMs with which it is connected and always creates just one connection to the connected JVM.
These connected JVMs could be server JVM to server JVM or client JVM to server JVM.

Features of T3 protocol

• High performance for various above said reasons
• Multiplexes various data sources data packets into single connection
• Minimizes the packet size

By default T3 protocol is configured to handle messages of size 10 MB, if server receives messages more than 10 MB size then it can not handle.

Solution: To Increase message size

1. Go to servers--->protocols--->general--->max message size--->change it to required value (It is preferable to have same size on both the admin and the soa servers)

2. Go to servers--->configuration--->server start--->arguments--->-Dweblogic.MaxMessageSize = same value given in previous step

3.Set weblogic.MaxMessageSize = 'required value' as system property on client side

4.Bounce client and the servers.