SNA Server Stops After Logging Event 684 and 685. (180619)

SYMPTOMS

The SNA Server service may stop unexpectedly and log the following Event ID in the Windows NT Event Viewer Application log:

Event ID: 685
Source: SNA Server
Description: An attempt was made to extend a buffer pool, but
the related pool had reached its maximum size. The affected component is terminating, and an audit of the buffer pools just before termination is attached

<the data will indicate a large number of trusted headers owned by the SNASERVR process >

This event will be preceded by numerous Event 684 messages, which indicate that the SNA Server's trusted header use is growing by about 150 per minute until the maximum trusted header pool is reached (of 100,000). When this occurs, SNA Server stops.

This problem coincides with the use of an APPC application that uses the DISPLAY API function to retrieve all LU6.2 configuration and state information.

CAUSE

When receiving an APPC DISPLAY request from an APPC application to retrieve LU6.2 information, SNA Server occasionally allocates an extra trusted header it doesn't actually use and then fails to free it.

STATUS

Microsoft has confirmed this to be a problem in SNA Server versions 3.0, 3.0 SP1 and 3.0 SP2. This problem is fixed in SNA 4.0.

This problem was corrected in the latest SNA Server version 3.0 U.S. Service Pack. For information on obtaining this Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K