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Jnc moved page Maintenance Operation Protocol to Maintenance Operations Protocol: Misspelled title: Per request

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The '''Maintenance Operation Protocol''' (usually abbreviated as "MOP") originated about 1976 as a part of the [[DECnet]] Phase II [[network]] [[protocol]] suite. It provides network services for management and maintenance.

== Naming Conventions ==

* A "host" is a [[computer]] that provides MOP services
* A "satellite" is a computer or network device that uses MOP services.

== Functions ==

MOP provides several functions:

* Down-Line loading (host to satellite) of memory contents, e.g. for booting diskless computers and network devices such as terminal servers
* Up-Line loading (satellite to host) of memory contents, e.g. for failure analysis
* Testing of network hardware and cabling
* Force satellite entry into the MOP mode, i.e. halt current satellite operation and put the satellite into MOP mode. This provides a means for the host to control an unattended satellite system.
* Remote Console

MOP works on the local network link only.

== Configuration ==

MOP is configured via the DECnet [[Network Control Program (DECnet)|Network Control Program]], (usually abbreviated as "NCP").
All configuration takes place on the host computer only.

Most NCP commands used for MOP configuration are identical for all versions of all DEC operating systems. The following examples are for DECnet [[VMS]] V4.0 and newer.

Activate MOP service on circuit <code>UNA-0</code> (= Ethernet device DEUNA or DELUA; replace with your network device type DECnet circuit-id):

$ '''MC NCP SET CIRCUIT UNA-O STATE OFF'''
$ '''MC NCP DEF CIRCUIT UNA-O SERVICE ENABLED'''
$ '''MC NCP SET CIRCUIT UNA-O SERVICE ENABLED STATE ON'''

This enables the host computer to answer any incoming MOP requests on network circuit <code>UNA-0</code>.

If the MOP request is a satellite download request (e.g. for booting), some parameters have to configured first, e.g.:

* Satellite DECnet address
* Satellite node name
* Load file
* ... and possibly others depending on the task to perform.

For details see the respective manuals.

== Debugging ==

For debugging purposes it is helpful to enable MOP related event logging (Examples for VMS V4.0 and later):

Enable [[OPCOM]] messages to the current terminal:
$ '''Reply/Enable'''

Enable DECnet logging to the OPCOM process:
$ '''MC NCP SET LOGGING CONSOLE STATE ON'''

Activate DECnet event 0.3 "Automatic circuit service":
$ '''MC NCP SET LOGGING CONSOLE EVENT 0.3'''

Activate DECnet event 0.7 "Aborted service request":
$ '''MC NCP SET LOGGING CONSOLE EVENT 0.7'''

== History ==

MOP underwent continuous development; the last known revision is 4.0.0, dating from 1992.
With the introduction of VMS V6.2 in 1995, MOP was decoupled from DECnet and integrated into the OpenVMS distribution with the new [[LANCP]] (LAN Control Program) command interface.

{| class="wikitable" style="text-align: center;
|+ MOP Revision History
|-
! Revision !! Date !! Reference
|-
| 1.1 || January 1976 || cited at: AA-D602A-TC Maintenance Operation Protocol, pdf page 37
|-
| 2.0 || March 1978 || [https://www.vaxhaven.com/images/9/9e/AA-D602A-TC.pdf AA-D602A-TC Maintenance Operation Protocol]
|-
| 2.1.0 || October 1980 || [https://www.vaxhaven.com/images/8/8b/AA-K178A-TK.pdf AA-K178A-TK DECnet Digital Network Architecture Phase III Maintenance Operation Protocol]
|-
| 3.0.0 || December 1983 || [http://decnet.ipv7.net/docs/dundas/aa-x436a-tk.pdf AA-X436A-TK DECnet Digital Network Architecture Phase IV Maintenance Operations Functional Specification]
|-
| 4.0.0 || June 1992 || [https://bitsavers.org/pdf/dec/decnet/EK-DNA11-FS-001_MOP_Functional_Specification_V4.0.0_Jun92.pdf EK-DNA11-FS-001 Maintenance Operation Protocol Functional Specification Version 4.0.0]
|}

== See also ==

[[DECnet]]

[[Category: DEC Networking]]
[[Category: DECnet]]

Maintenance Operations Protocol - Revision history

Jnc: Jnc moved page Maintenance Operation Protocol to Maintenance Operations Protocol: Misspelled title: Per request

Vaxorcist: New page: Maintenance Operation Protocol