DTSS too few servers message

[Antoniov.]

After upgraded decnet from IV to V I see on console periodically a message like:
DTSS too few servers detected

Reading documentation I understand system can't try a datatime server.
How I can solve?
May I set this server as DTSS server?
May I set old server (with decnet IV) as clerk?

Every help will be appreciated.
Antonio Vigliotti

[Uwe Zessin · Accepted solution]

I never needed a DTSS, so I put this in SYSTARTUP_VMS:

$ run SYS$SYSTEM:NCL
DISABLE DTSS
DELETE DTSS
EXIT
$

It is possible that you can prevent the start of DTSS through a logical name these days, but I haven't seen a Ph IV system for some time now.

[Ian Miller.]

Each dtss clerk (client) is looking for servers to sync with. You can see how many its looking for with
MCR NCL SHOW DTSS SERVERS REQUIRED.
Its usually 3. It looks on the local lan. If you do have some DTSS servers elsewhere you can added them to SYS$MANAGER:DTSS$CONFIG.DAT as "Global DECNET DOMAIN:.a.b.c"

You can reduce the servers required although 3 is best. You can setup DECnet/Plus system as a server. You can turn off DTSS and use NTP. It depends on your setup.

[Bojan Nemec]

Antonio,

Setting this server as a DTSS server will not solve yours problem. It needs almost 3 time servers to work properly. So Uves solution will be better (I use the same when DECnet V is needed, I like much more IV)

Bojan

[Wim Van den Wyngaert]

Antonio,

The message normally includes "Number detected" and "Number required". If you only did an upgrade, the configured number required probably changed. Compare with another node (mc ncl sho dts ser req).

If number detected is zero, you might have network problems.

Wim

[Antoniov.]

Hi,
If I understand DTSS give distribution of time server across network.
Used Uwe's command to avoid message.

may I set this as DTSS server?

Antonio Vigliotti

[Ian Miller.]

DTSS is a way of syncronising time amonst distributed systems. You can set your system to be a DTSS server. However by default systems are looking for three servers so this probably won't stop the message. By disabling DTSS you can stop the message but then should use someother form of time syncronisation. You can permenantly disable DTSS by renaming/removing SYS$MANAGER:NET$DTSS*.NCL

[Wim Van den Wyngaert]

Uwes command disables DTSS completely.
Check *dts*.ncl in sys$manager to adjust the config (empty it when needed). But are you using dtss on your site or not ?

Wim

[Jan van den Ende]

Antonio,

Uwe's solution DOES stop the repeating messages, after maybe a few between starting it and stopping it again.

The way to PREVENT it from starting is a SYSTEM_WIDE, logical name NET$DISABLE_DTSS, with any TRUE value.

Define this logical sufficiently EARLY in the bootstrap, ie, in NET$LOGICALS.COM

As the name suggests, this disables DTSS startup.

--- This becomes especially vital if NTP will be used, as is becoming ever more the case in environments where NOT all systems are running DECnet :-(


Jan

[Antoniov.]

Ian, Wim,
found NET$DTSS_CLERK_STARTUP.NCL so I guess my system start as clerk. Reading into it I saw syntax to I tried issue follow command:
$ MC NCL CREATE DTSS TYPE SERVER
System answered me:
%NCL-E-CMLSENDFAILED, error sending command request
-CML-E-EMAAPROB, error returned from VMS EMA agent
-NCL-E-ENTCLSNOTSUPP, entity class not supported

Jan,
not system logical found; I've only NET$LOGICALS.TEMPLATE in my system.

I never used DTSS service (because I never used Decnet V); now in my mind, using this service I can set one host as time server; isn't true?
Because I want understand how this work, I prefer set this one as unique time server (vms V7.3-2, decnet V) while old server (vms V6.2, decnet IV) become client (clerk).
If old server cannot work as client, I'm avaiable to install decnet V on it.
I'm convinced unique time server is secure but I will understand how this work and I will practise decnet V.

Thank you
Antonio Vigliotti

[Uwe Zessin]

Antonio,
before you try out the DTSS server, I suggest you check your DECnet license. I _think_ you need a full function (DVNETRTG or DVNETEXT) license for this.

[Jan van den Ende]

Antonio


not system logical found; I've only NET$LOGICALS.TEMPLATE in my system


That file is exactly what the name suggests: a template with a lot of DECnet steering logicals.

If you want/need ANY network function to be somewhat other than the default, THEN you copy the .TEMPLATE to .COM, and make the adjustment.
Most functions are already there, just commented out.
DTSS disable you will have to add yourself.

And yes, DECnet V (or Plus, as I think is today's name) has A LOT of functionality, with A LOT of not-so-easy syntax. It allows for A LOT of 'fun'.

Success
Jan

[Antoniov.]

Uwe,
thank you for warning.
I received from HP a lot of license (time limited) as software development, so I'm learning about some new software (as Decnet V). On new server I've installed both licenses. I prefer leave old server as is (because it's production server) while new server is only for testing.

Jan,
I'm reading NET$LOGICALS.TEMPLATE to understand something about DTSS.

Tahnk you.

[Mohamed K Ahmed]

Antonio,

This is a known issue and to eliminate these messages you can add this line to your systartup_vms.com file

$ mcr ncl block event dispatcher outbound stream local_stream global filter ((Node, DTSS), Too Few Servers Detected)

HTH

Mohamed

[Wim Van den Wyngaert]

Mohamed,

That isn't a solution. It simply removes the message but the software is still detecting it.

Wim

[Mohamed K Ahmed]

Wim,
I didn't say it is a solution, I said "to eliminate this message"

If I can just find the document that talks about this I will post a solution, I know I have it somewhere...

Mohamed

[Ian Miller.]

See also NET$EVENT_LOCAL.TEMPLATE

Often now its a IP only network so disable DTSS has described and config NTP instead.

[Mohamed K Ahmed]

This comes from the OpenVMS Ask the Wizard section on the hp.com website

You have apparently chosen DECdtss and DECnet-Plus while upgrading, and you do not
have any DECdtss time servers configured.

You can configure a DECdtss time server per the DECdtss documentation, you can disable reporting these messages, you can disable DECdtss, or you can downgrade to DECnet Phase IV.

To disable DECdtss on the local node, use the commands:

$ run sys$system:ncl
ncl> disable dtss
ncl> delete dtss

[Uwe Zessin]

Well, Mohammed, I thought I suggested that a few hours ago...

[Mohamed K Ahmed]

Please disregard my last posting, here is what I meant:

This comes from the OpenVMS Ask the Wizard section on the hp.com website

You have apparently chosen DECdtss and DECnet-Plus while upgrading, and you do not
have any DECdtss time servers configured.

You can configure a DECdtss time server per the DECdtss documentation, you can disable reporting these messages, you can disable DECdtss, or you can downgrade to DECnet Phase IV.

To disable DECdtss on the local node, use the commands that Uwe mentioned a few hours ago !!

[Wim Van den Wyngaert]

I would stick to the logical net$disable_dtss because this is also tested in vms$baseenviron-50_vms.com when doing startup of utc.

Wim

[Uwe Zessin]

I agree that the logical name solution is better than my first response - if you re-read my text you'll see that I even mentioned that there might be a logical name now, but I wasn't sure / could not remember.

In the third response I just wanted to point out that the hint about disabling DTSS wasn't new.

[Antoniov.]

Hi,
message successfully disabled :-)
I'm interesting into DTSS using.

Antonio Vigliotti

[Ian Miller.]

To use DTSS you need three servers and other nodes are clients. If all nodes on the same lan then configure the three servers and the other nodes will find them. If not on same lan then add names of servers into DTSS$CONFIG.DAT on all nodes.

DTSS servers will agree what time it is and tell the others.

[Wim Van den Wyngaert]

Antonio,

here an extract of my notes of long time ago.


Q>How does dtss works ?
-----------------------
There are 3 types of processors :
. local servers : those nodes that understand the multicast messages will
participate in the synchronization (LAN)
. global server : WAN, use decnet thru a bridge (multicast is blocked by bridge)
. couriers servers : these will synchronize global and local servers and
propagate the newly calculated values locally.
The courier node can have backup nodes.

A clerk is a process (DTSS$CLERK) that sends multicast messages to servers to
know of their existence. The servers themself also use multicast messages to
make them self known. This is done using the dtime protocol. With the responses
the clerk makes a list of servers. It will then query a number of servers to
know each of their times. The clerk will calculate a new time and correct its
clock. All servers that are reachable with multicast will be taken into
account.

A server is a process (DTSS$SERVER) that periodically synchronizes its time with
all known servers. Local servers with role courier synchronize with at least 1
global server and all local servers (courier and backup courier). Those that
have no courier role or only a backup courier role will not syncronize with
global servers.

The global servers receive the external time and adjust their clock. The local
courrier servers will synchronize with the global server. All servers will
synchronize themself in group. The clerc synchronizes with a number of servers.

Based upon the difference between a node's time and this average, the
historical data of this node is updated. A rating is assigned to the node
so that this node can calculate its own expected drift. It is called
the inaccuracy. It is also fed back into the algorithm (to find the
times that are not reliable and will not participate in the computation
of the average time).

If a (external) time provider server (tp server) has passed its time,
it will be used without further discussion.