another problem with NCP

[SCC_2]

Hello,
Run Micro VAx 3100 model 90 and have pathwork link to Pc. Beem running great for years.
Today don't work, error directory look up failure...

I check the ncp - sh node all2
usually it said 1.2 (all2) sva-0 0
today it said 1.2 (all2) unreachable

the excutor node 1.1 (alspan0 status = 0 looks o.k.

what wrong with it this time.
Thanks !
SCC

[Uwe Zessin]

If node ALL2 is still running, then it very much looks like a network probem. DECnet nodes exchange so-called 'hello' messages every few seconds with the DECnet router nodes. If the 'refresh' does not happen any longer, the node goes into state 'unavailable'.


Node ALL2 could be an 'end-node' that does not understand the network's topology. Node ALSPAN apparently is a router and knows how to send packages in a more complex network. In that case ALL2 sends data for nodes it cannot reach directy to ALSPAN which makes sure the data goes the correct way.


Assuming that the PC is still running and no one has made any changes to it, I would first check the network cabling. Most likely this is a 10BASE2 ('thin-wire') cabling. Check if somebody has made a change, here. Is the segment terminated correctly at both ends? Is it really a network segment or has somebody cabled it as a "T"?

If DECnet event logging is set up,
NCP> show known logging

will tell you, then you might be able to look into OPERATOR.LOG to find out when node ALL2 went offline the last time.


Network problems can be very nasty - I've heard a story about an IT manager's office where a network segment ended at the back of his seat. When ge got bored, e.g. in meetings, he pulled the terminator from the segment, played with it a little and then put it back. You can imagine that the network people only found this out by pure luck!

[Wim Van den Wyngaert]

My first action always is checking if lat is still working with set host/lat xxx. That is, if lat is not disabled. If it works, the network is there but not working for decnet (router missing, bad setup ...).

Wim

[Volker Halle]

SCC,

does the MicroVAX see other DECnet-nodes on your network (e.g. node ALL5 1.5) ? If not, the problem may also be on the MicroVAX network connection. Can ALL5 communicate with ALL2 (try: NCP TELL 1.5 SHO EXE from node ALL2).

Volker.

[Antoniov. · Accepted solution]

Hi SCC,
try follow steps:
1. If you can use another network protocol like $ SET HOST/LAT or $ TELNET. After of this you know if your machine is physically connected to network.
2. $ MC NCP SHOW KNOW CIRC
I guess you see SVA-0 in synchronising state. If yes your machine can't comuicate with other server; may be somethink like unplugged cable. If your circuit is ON the trouble is focused on ALL2 node.
You can also see statistic counter with
$ MC NCP SH KN LINE COUNT
$ MC NCP SH KN CIRC COUNT

Antonio Vigliotti

[comarow]

I would start off with replacing the cable.

Were there any messages about networking not starting?

Does set host/0 work? That shows that DECNET software is working.

[SCC_2]

Thank you for so many of you people trying to help. When I type ncp: sh known node
it show
executor node = 1.1 (alspan)
state = on
idenfication = decnet-vax v5.5-2, vms v5.5-2
1.2 (all2) unreachable

I check the 10baset cable, can't really tell they are bad or not, until I go and get some new one to test.

but no matter what I did it still showing
node 1.2 (all2) state unreachable.

I try to follow the manual and type

set circuit sva-0 state on max routers 5
come back error
%ncp-w-opefai, operation failure
%system-f-nolicense, operation requires software license

I don't think I see this before.
will this cause the problem that not to work ?

Thanks !
SCC

[Volker Halle]

SCC,

VMS is very good at keeping status and counter information to help you troubleshoot any problem, but you need to know where to look for. So some basic understanding of the software components is needed for troubleshooting...

This node seems to be an ENDNODE (you can check this with NCP SHOW EXE CHAR) - it would need a DECnet routing license for setting CIRC MAX ROUTERS and it doesn't seem to have one.

An ENDNODE does not know about the reachability of other endnodes, it only knowns, if there is a valid functioning network circuit and maybe a router on the network (shows as NEXT NODE in NCP SHOW KNO NODES).

If SVA-0 (your DECnet CIRCUIT) is NOT listed, then it looks like that circuit is not in the ON state, so there is no way to get out of your node with the DECnet protocol. Please check with NCP SHOW KNO CIRC - SVA-0 must be in ON state. If it isn't, check NCP SHOW KNO CIRC COUNTER and even more important NCP SHOW KNO LINE COUNTER. Are there any error counters non-zero and probably incrementing ?

Volker.

[Antoniov.]

Hi SCC,

$ MC NCP SHOW KNOW CIRC
I guess you see SVA-0 in synchronising state. If yes your machine can't comuicate with other server; may be somethink like unplugged cable. If your circuit is ON the trouble is focused on ALL2 node.

You can also see statistic counter with
$ MC NCP SH KN LINE COUNT
$ MC NCP SH KN CIRC COUNT

Antonio Vigliotti

[SCC_2]

Hello,
when I type sh kn cir come back
no information in database

when I type sh kn line it show sva-0 state on
but not on cir.

Scc