Re: What TCP interface is used by NTP

Thanks Stefan, Marc,Jack, Rob

The NTP client is configured to seek one in-Lan Time server as well as
a public one .
Looking at the logs (like QTOT20220716) in /QIBM/USERDATA/OS400/TCPIP/NTP/
I see that when started (using the correct IP interface) it pulls the time
from the public one
(192.114.63.250).

I'll try CHGTCPRTE .

Thanks again
Gad

date: Wed, 13 Jul 2022 08:02:05 -0600
from: Jack Woehr via MIDRANGE-L <midrange-l@xxxxxxxxxxxxxxxxxx>
subject: Re: What TCP interface is used by NTP ?

This should work:

CFGTCP -> 2. Work with TCP/IP routes

Change TCP/IP Route (CHGTCPRTE)



Type choices, press Enter.



Route destination . . . . . . . > '*DFTROUTE' Character value,
*DFTROUTE...
Subnet mask . . . . . . . . . . > '*NONE' Character value, *NONE,
*HOST
Type of service . . . . . . . . > *NORMAL *MINDELAY, *MAXTHRPUT...

Next hop . . . . . . . . . . . . > '123.456.789.000'

Preferred binding interface . . > *NONE Character value, *NONE

Maximum transmission unit . . . *IFC 576-16388, *SAME, *IFC

Route metric . . . . . . . . . . 1 1-16, *SAME

Route redistribution . . . . . . *NO *SAME, *YES, *NO

Duplicate route priority . . . . 5 1-10, *SAME, *HIGH...

Text 'description' . . . . . . .


Add some new route destinations to the several NTP servers and choose the
"Preferred binding interface".
Don't change the *DFTROUTE shown above, I'm just pasting in the panel to
show you what it looks like.

On Tue, Jul 12, 2022 at 10:48 PM Gad Miron <gadmiron@xxxxxxxxx> wrote:

Is there a way to configure the IP interface for NTP ?

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date: Wed, 13 Jul 2022 16:12:49 +0200
from: Stefan Skoglund <stefan.skoglund@xxxxxxx>
subject: Re: What TCP interface is used by NTP ?

ons 2022-07-13 klockan 13:22 +0000 skrev Rob Berendt:

Stephan,

I think the OP's problem was that, for some reason, his company is
only letting certain IP addresses attach to the NTP server.? And
instead of allowing all the IP addresses serviced by his lpar of IBM
i they'd like him to restrict it to just one.
Frankly IDK what the big deal is to restrict access to the NTP server
might be.? Wouldn't all PC's have to sync also?
Maybe the IBM i acts as an NTP client to get to that NTP server and
then acts as the NTP server for the rest of the network?

Rob Berendt

One question: can IBM i run as a NTP server ?

192.168 is private IP adresses so Gad's company probably has a NTP
server somewhere in their network.

My reading of the IBM doc
(
https://www.ibm.com/docs/en/i/7.4?topic=protocol-scenario-synchronizing-clocks-i
)
is that timekeeping on
IBM i is restricted to NTP client and SNTP (client/server.)

Gad's trouble could maybe be ameliorated. Is it possible to tell the
(S)NTP client to only use a specific source IP address ?

The doc especially doesn't say if is possible to nominate multiple time
sources, so is it possible to nominate 4 sources.
With at least 3 sources, it is possible for the host to decide if one
of the sources has an unstable clock (ie it is a possible?
false-ticker) and so marking it as not-legitimate (a status which can
be reversed.)

How many i Systems is in the 10.10.10 net ?
Is it only the peer or is it more ?