topic Re: Decnet problems in Operating System - OpenVMS

Decnet problems

Wim Van den Wyngaert — Thu, 09 Feb 2006 06:54:02 GMT

I have node A and B in the same decnet area.

On A, I do set host B and get "remote node is not currently reachable".

I go to B with TCP and try set host A. It works.

I retry on A to do set host B. It works too.

Some time later on, it no longers works.

What's wrong ?

Wim

Re: Decnet problems

Karl Rohwedder — Thu, 09 Feb 2006 07:08:10 GMT

Do you have Phase V and DEcnet-over-IP?
Maybe the nameresolution is different. Try
running CDI$TRACE from a 2nd terminal and check what is going on.

regards Kalle

Re: Decnet problems

Wim Van den Wyngaert — Thu, 09 Feb 2006 07:09:38 GMT

Decnet+ on VMS 7.3. Also 6.21H3 can not communicate with the host.

Transport is NSP.

Wim

Re: Decnet problems

Volker Halle — Thu, 09 Feb 2006 07:41:17 GMT

Wim,

the fact that it works for a while after you've done B: SET HOST A can be explained by the end-node cache. An end node remembers (for some time) which node it has been communicating with.

To get naming out of the picture and DECnet-over-IP, just repeat your tests using the plain DECnet adresses.

Volker.

Re: Decnet problems

Wim Van den Wyngaert — Thu, 09 Feb 2006 08:49:49 GMT

Addresses don't work either.
No TCP involved.

Wim

Re: Decnet problems

Volker Halle — Thu, 09 Feb 2006 08:59:09 GMT

Wim,

how many routing circuits on node A and node B ? End nodes or routing nodes ?

Is a router involved (NCL SHOW ROUT CIRC csmacd-a ADJ * ALL) ? If so, it's the router's job to find a path to the remote node. Once a path has been found, the end node (using the address data in the end-node cache) can communicate directly (assuming both nodes are on the same LAN).

Volker.

Re: Decnet problems

Wim Van den Wyngaert — Thu, 09 Feb 2006 10:57:35 GMT

Volker,

Sorry for the delay, internet not working properly.

On A : 1 router. On B : none. They are not configured manualy on VMS. Is something missing in network config ?

Wim@home

Re: Decnet problems

Volker Halle — Thu, 09 Feb 2006 11:06:11 GMT

Wim,

there's something wrong in the network config or router. But this explains, WHY you can do B: SET HOST A - an end-node without a router just tries to send the packet out on the LAN - and it works !

Then (for some time) A can also do SET HOST B, as node B's address is in it's endnode cache. Once this times out, A has to ask the router, which does NOT seem to know about node B.

Node B does not seem to see the Router Hello messages and the router does not seem to see node B's endnode hello messages. (DECnet) Multicast messages blocked ?

You could use TRACE START/LIVE "routing circuit csmacd-0" on node B to see if it receives any router hello messages.

Volker.

Re: Decnet problems

Wim Van den Wyngaert — Thu, 09 Feb 2006 14:37:21 GMT

Will come back on it on Monday.

Thx Volker.

Wim

Re: Decnet problems

Wim Van den Wyngaert — Mon, 13 Feb 2006 01:30:45 GMT

It seems that hello messages are seen for the wrong area. Time to call the network team.

Wim