Celebrate National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

OpenVMS Systems: DECNET and Two NIC Interfaces

Posted on 2011-03-11
1
Medium Priority
?
1,024 Views
Last Modified: 2012-06-22
I have a system with two NIC interfaces. The NICs are attached to CISCO switches over a multi-building campus. NIC 1 is configured for EWA0: and has an IP address configured on the 10.0 network. NIC 2 is configured for EWC0: and has an IP address configured on the 100.0 network.

The problem, an OpenVMS system across campus is on the 100.0 network and DECNET seems to be attached (Circuit is defined) to EWA0: and not EWC0:

The Circuit status is up for both connections and the line is associated with the MAC address of NIC #2 for EWC0:

How does one hard-wire DECNET to use a specific Circuit / Line / NIC interface?

I attempted a set/define node <address> name <node name> circuit EWC0 and DECNET displayed an error.

I have not tried to set the EWA0: state to disabled... but would DECNET know to connect to EWC0?  I was told DECNET broadcasts on all interfaces and selects and interface which responses to a "hello" broadcast.

Any thoughts on this?

Thanks!
 
0
Comment
Question by:TimPeer
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 40

Accepted Solution

by:
noci earned 2000 total points
ID: 35118181
DECnet has NODE addresses (a MACHINE has one address) not in interface.
IP has interface addresses... there fore a machine has at least one address per interface.

Also in IP there are separate queries done to get translations for IP -> MAC (the ARP protocol).
In DECnet the MAC address is set to a variant of the DECnet address...
==> All interfaces that are KNOWN to DECNet (ie the have a circuit & line ) definition then the MAC address is converted during boot time, to prevent MAC address change issues later on.

This causes the requirement that two interfaces of a system MAY NEVER carry DECnet in the same broadcast domain (Layer-2 (V)LAN).

If you want the interface changed then just remove the xx-0 interface and create a xx-2 interface.
The exact xx- is dependant on your interface.     if you have XXA0 & XXC0 then you have XX-0 & XX-2 respectively.

so it is:

LIST CIRCUIT XX-0 ALL
DEFINE CIRCUIT XX-2 STATE ON
DEFINE CIRCUIT XX-2 .....   (any parameters you can copy form the currnt XX-0)
LIST LINE XX-0 ALL
DEFINE LINE XX-2 STATE ON
DEFINE LINE XX-2 .....    ( Any parameters from previous XX-0)
SET KNOWN CIRCUITS ALL
SET KNOWN LINES ALL

! If you need to remove XX-0 then use the following
PURGE CIRCUIT XX-0 ALL
PURGE LINE XX-0 ALL
SET CIRCUIT XX-0 STATE OFF
SET LINE XX-0 STATE OFF
CLEAR CIRCUIT XX-0 ALL
CLEAR LINE XX-0 ALL
! The MAC address will only be cleared on REBOOT.

Replace all XX in above with the correct interface name (Probably EW).
And yes if the interface comes up it will detect other systems in the vicinity and start coomincating if they are within the SAME area. (onther wise you need an extra routing license to do level-2 routing.

0

Featured Post

Veeam Disaster Recovery in Microsoft Azure

Veeam PN for Microsoft Azure is a FREE solution designed to simplify and automate the setup of a DR site in Microsoft Azure using lightweight software-defined networking. It reduces the complexity of VPN deployments and is designed for businesses of ALL sizes.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Please see preceding article here: http://www.experts-exchange.com/Networking/Operating_Systems/A_11209-Root-Bridge-Election.html Figure 1 After Root Bridge has been elected, then what?..... Let's start by defining a Root Port in la…
Configuring network clients can be a chore, especially if there are a large number of them or a lot of itinerant users.  DHCP dynamically manages this process, much to the relief of users and administrators alike!
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question