how to reconfig the hardware address

[Wim Van den Wyngaert]

I'll retry.

Your network card had address A.

Decnet starts and calculates a new address B based upon the decnet address. From then on, all network protocols that start will use that address B.

If you assign the decnet address to another node and stop the old node, the address with which the new node will communicate is the same as that of the old node (that is B).

Study hard !

Wim

[lovexeagle]

what I want to know is why my "clone" system can not communicate to the old network through decnet Address ?

Does I must reconfig the DECnet Address?

if not, what the problem can make the network crash.

thanks for your patient answerï¼ you are a good guy :)

[Wim Van den Wyngaert]

Not sure what you mean with "clone".

if you have 2 nodes on the same network with the same decnet config, you are in shit. 2 nodes will fight for the network packages. Result will be very messy (didn't try it yet). You will have to rename 1 of the 2 nodes or put 1 out of order (power off).

Wim

[lovexeagle]

the word "clone" is from karl :).
I mean "backup/image" from A to mathine B
what I want to do is B does the same function as Aã B is a backup system of Aã
they will not appear in the same network at the same timeã

[Karl Rohwedder]

If system B is only connected to the network, if system A is down, you may leave all addresses unchanged, so that B may work as A in case of problems.

I attached a (quite crude) DCL procedure, which converts DECnet addresses to their AA... equivalent and vice versa for your information.


regards Kalle

[Wim Van den Wyngaert]

Then read this one.
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1038607

If the hardware is the identical the machine should work without change (licenses ?). Otherwise you might encounter some problems.

Wim

[Jan van den Ende]

lovexeagle,

To begin with:
WELCOME to the VMS forum!

What is not yet clear to me:
Is the _ORIGINAL_ node (from which you made the system disk Backup) running at the moment?

If so, than you would be trying to get two same MAC-addresses in your network, which will not work, and therefore, you MUST reconfigure DECnet to a unique address (let's say, you chose x.y) Be sure to change SYSGEN parameter SCSSYSTEMID to (1024 * x) + y. You will then need a reboot.
After that, you get a new AA:00:.. MAC address (it is calculated automaticly).
Now you have a network, and you can configure IP.

Note: this ONLY applies when the original node of that system disk is still running, and on the same network. If not, forget about this post.

Hope this helps.

Success.

Proost.

Have one on me.

jpe

[William Brown_2]

You also need to check the id of the network card in the old vs the new system. If they are the same ethernet cards and the same number of cards, then it should be the same. If different you need to check...could be EIA or EWA depending on the cards.

On a running system (with phase IV Decnet)
go into NCP and give the command SHOW KNOWN CIRCUITS. This will show the known devices and their states (-ON should mean working, -off not working, -starting probably means trying but having a problem.) Also, NCP command SHOW KNOW LINES will show know lines of which some might not be know to DECnet.

You might even need to run NETCONFIG.COM to get DECnet configured with the correct config for the 'new' system if different than the old (so that DECnet has seen all the lines AND circuits).

Just some more of the many possibilities depending on the situation.

Good day,

Bill

[Colin Butcher]

Hello,

OpenVMS systems can run many network protocols, not just TCP/IP. Typically you will find the following protocols in use with ethernet network interfaces:

- SCS (a layer 2 protocol used for cluster traffic)
- LAT (a layer 2 protocol used for terminal and printer traffic, usually with terminal servers, otherwise known as DECservers)
- MOP (a layer 2 protocol used for down-line loading devices, often DECservers and cluster satellites)
- DECnet (a layer 3 protocol used for node to node communication)
- TCP/IP (a layer 3 protocol used for node to node communication)

These different protocols all work in different ways and can all co-exist on the same network interfaces.

The ethernet specifications require each network interface to have a unique address - known as the MAC address (Media Access Control). The MAC address is usually based on a unique number contained in ROM on the network interface and is known as the hardware MAC address.

The interface operates with the physical MAC address, which is usually loaded from the hardware MAC address, but it can be set by the network layer drivers to an alternate value. DECnet Phase IV (and Phase V in Phase IV compatible mode) sets the physical MAC address to a known value based on the DECnet Phase IV node address.

DECnet node addresses have the format

[Chinraj Rajasekaran]

Hi,

there is a useful list in the VMS FAQ
Section 5.7
http://h71000.www7.hp.com/faq/vmsfaq_007.html#mgmt9

Cheers
Raj