  DECnet MOP Download DATACHECK OPCOM? 
 The Question is:
 
Hi,
 
I keep getting these OPCOm Message:
 
%%%%%%%%%%%  OPCOM  23-AUG-2000 12:14:04.46  %%%%%%%%%%%
Message from user DECNET on SKBV00
DECnet event 0.3, automatic line service
From node 36.10 (SKBV00), 23-AUG-2000 12:14:00.27
Circuit MNA-0, Load, Line communication error
%SYSTEM-F-DATACHECK, write check error
Node = 13.104 (SKBS04), File = MOM$SYSTEM_SOFTID:SH1601ENG
Operating system, Ethernet address = 08-00-2B-26-7F-B3
 
%%%%%%%%%%%  OPCOM  23-AUG-2000 12:47:51.10  %%%%%%%%%%%
Message from user DECNET on SKBV00
DECnet event 0.3, automatic line service
From node 36.10 (SKBV00), 23-AUG-2000 12:47:46.58
Circuit MNA-0, Load, Line communication error
%SYSTEM-F-DATACHECK, write check error
Node = 13.100 (SKBS00), File = MOM$SYSTEM_SOFTID:SH1601ENG
Operating system, Ethernet address = 08-00-2B-26-86-14
 
 
What does this mean?
 
This is coming from two DECServer 300 terminal servers.
 
 
 The Answer is:
 
  This message is originating from a error detected by DECnet Phase IV
  on an OpenVMS VAX node, with the error resulting from a failed MOP
  download operation.  The failure is occuring because the DECserver 300
  is repeatedly requesting a download of the SH1601ENG file.
 
  This error could be caused by a network hardware problem (check for
  various counters incrementing in your NCP database), or by excessive
  collisions, or potentially by a MOP protocol mismatch (V3 vs V4).
 
  If you should see Remote Failure to Defer, Block Check and Framing
  Errors, these are generally indicative of network hardware problems
  -- though these Block Check and Framing Errors do not usually cause
  DATACHECK errors.
 
  An attempt at downloading the same device blocked by a parallel MOP
  download -- this can arise with multiple nodes answering the same MOP
  request -- usually does not produce DATACHECK errors.
 
  The OpenVMS Wizard would check the firmware revision of the DEMNA module,
  and would also inspect the Ethernet cabling for validity -- including a
  check to ensure the total length of the LAN segment does not exceed the
  limits, and to check that the number of bridges or repeaters included
  in the segment does not exceed the limits.
 
  The OpenVMS Wizard would also generally move to LANCP for MOP downloads
  and related operations.
 
  As more information will be required, please contact the Compaq Customer
  Support Center.
