PROBLEM:
In theory and in most cases having jumbo frames enabled in a network has been proven to increase network performance and reduce CPU overhead. It is possible that it may also cause inconsistency or incompatibility with certain network protocols or applications.
This article is to specifically highlight one case where there was evidence of an incompatibility with the Traverse WMI Query Daemon.
SOLUTION:
If the following symptoms are exhibited, please review the environment settings and disable the 'Large Send Offload' feature on the NIC for the DGE to see if the issue is resolved. A server reboot is required after this change has been made.
- All WMI tests monitored by a specific DGE(-X) or proxy go unreachable or unknown.
- WMI Query Daemon stops working (component is still running and no sign of a crash)
- monitor.log shows:
m.c.w.s.WmiQdNetworkClientImpl$TelnetClientHandlerNew I/O worker #1: (WARN ) Unexpected exception from downstream. : null - Wireshark capture shows (attached)
.