Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Thu, 2 Aug 2007 18:22:35 -0600

Hello Mike,

The CA UDP server spits out that message when it receives a datagram with
undecipherable protocol.

If there is substantial multi-bit damage in the datagram it can slip through
the UDP and Ethernet CRC checksum validations. Watch out for vxWorks
auto-negotiation problems with {10/100} and {full duplex/half duplex}
Ethernet that can occur if the vxWorks system is turned on before the switch
is. Also watch out for invalid termination and or branching of legacy coax
based Ethernet. There can also be intermittent issues with copper Ethernet
cables that pass close to electronic noise sources. Look for non-zero error
counts in the output from "ifShow".

Does the CA based communication function correctly after the IOC boots?

Jeff

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Laznovsky, Michael
Sent: Thursday, August 02, 2007 5:33 PM
To: EPICS Tech Talk
Subject: "invalid UDP request" during boot

Hi- anyone know what these "invalid UDP request" messages mean?  They've 
just started appearing during the boot of an mv2700/R3.13.10 vxWorks IOC. 
The numbers after "gtw01:" appear to be port numbers mostly associated with 
edm processes on solaris machines.

thanks,
Mike

-----

# Start EPICS
iocInit( getenv("RESOURCE_DEF") )
############################################################################
Starting###   iocInit
@(#)EPICS IOC CORE built on Oct  9 2006
###  @(#)Version R3.13.10 $2004/04/15 13:36:02$
############################################################################

iocInit: All initialization complete
CAS: invalid (damaged?) UDP request from gtw01:46316 ?
CAS: invalid (damaged?) UDP request from gtw01:39871 ?
CAS: invalid (damaged?) UDP request from gtw01:46316 ?
CAS: invalid (damaged?) UDP request from gtw00:36836 ?
CAS: invalid (damaged?) UDP request from gtw00:44255 ?
CAS: invalid (damaged?) UDP request from gtw01:45271 ?
CAS: invalid (damaged?) UDP request from gtw00:45758 ?
CAS: invalid (damaged?) UDP request from gtw01:46316 ?
...

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System