To put in the fix for this issue, you’ll have to edit the domain.xml file (for your domain) and look for the following line:
<connection-pool max-pending-count="4096" queue-size-in-bytes="4096" receive-buffer-size-in-bytes="4096" send-buffer-size-in-bytes="8192"/>
Change the figure in receive-buffer-size-inbytes, to the below :
<connection-pool max-pending-count="4096" queue-size-in-bytes="4096" receive-buffer-size-in-bytes="8192" send-buffer-size-in-bytes="8192"/>
The above line may appear many times within domain.xml, it’s okay to update all of them.
After that restart the domain and clusters and retest. The problem should go away.