utc date set back to cdt by ntpd - Redhat

This is a discussion on utc date set back to cdt by ntpd - Redhat ; I "inherited" a standalone network with a linux box and a trimble GPS with the trimble driver setting the system clock and using that 1pps time signal. IANE, but I installed ntpd and set it to think it was a ...

+ Reply to Thread
Results 1 to 6 of 6

Thread: utc date set back to cdt by ntpd

  1. utc date set back to cdt by ntpd

    I "inherited" a standalone network with a linux box and a trimble GPS with
    the trimble driver setting the system clock and using that 1pps time signal.
    IANE, but I installed ntpd and set it to think it was a stratum 1. If I
    type "date" I see UTC time which is what I want. Now I want the other
    non-trible boxes to use my UTC time to sync. Currently they are all CDT
    (central time zone).

    On my other linux boxes i set up ntpd to use that server. They all have CDT
    instead of GPS even after syncing to the server. When I bring up
    redhat-config-date I cannnot advance the CDT to UTC unless I take the check
    off the "Enable Network Time Protocol". I can then set it up to UTC and the
    system clock advances by the 5 hours as it should. Putting the [x] back
    into "Enable Network Time Protocol" causes the time to go back to CDT as
    soon as the time is synced. The other dialog box "Time Zone" has a
    checkbox for [x] "System clock uses UTC" Putting or removing the "x" makes
    no difference. Anyway, I cannot get the UTC to stick as everytime I dismiss
    the Date/Time property box, the timesync reverts me to CDT.

    IANE on redhat linux and it seems that I do not know how to set the time
    zone to "UTC" as the system date is always CDT, not UTC. How do I go about
    changing the time to UTC?


    ...thanks in advance..

    ================================================== =====================
    Joseph Stateson antispam@sbcglobal.net
    Seti WU 50K Seti Years 51 Ask about my 99'R1100RT
    Least we forget... http://tinyurl.com/3amm5
    ================================================== =====================





  2. Re: utc date set back to cdt by ntpd

    "Beemer Biker" wrote:

    > I "inherited" a standalone network with a linux box and a trimble GPS
    > with the trimble driver setting the system clock and using that 1pps time
    > signal. IANE, but I installed ntpd and set it to think it was a stratum
    > 1. If I type "date" I see UTC time which is what I want. Now I want
    > the other non-trible boxes to use my UTC time to sync. Currently they
    > are all CDT (central time zone).


    Whether or not your time is synchronized properly has absolutely nothing to
    do with what timezone your machines think they are in. If it did, then you
    couldn't use NTP time servers around the world to help set your time
    correctly on your local server.

    As far as servers are concerned, everything is done relative to UTC. It's
    simply a display matter as to whether or not they show the time as
    converted to EST5EDT, CEST, or whatever.

    Now, another factor is that you shouldn't set your stratum within the NTP
    configuration. If you're using a GPS refclock and the GPS refclock driver
    for it, your server should automatically set the refclock to Stratum 0, and
    therefore it automatically becomes Stratum 1.

    > On my other linux boxes i set up ntpd to use that server. They all have
    > CDT instead of GPS even after syncing to the server. When I bring up
    > redhat-config-date I cannnot advance the CDT to UTC unless I take the
    > check off the "Enable Network Time Protocol". I can then set it up to
    > UTC and the system clock advances by the 5 hours as it should. Putting
    > the [x] back into "Enable Network Time Protocol" causes the time to go
    > back to CDT as soon as the time is synced. The other dialog box "Time
    > Zone" has a checkbox for [x] "System clock uses UTC" Putting or removing
    > the "x" makes no difference. Anyway, I cannot get the UTC to stick as
    > everytime I dismiss the Date/Time property box, the timesync reverts me
    > to CDT.


    This is an OS/user interface issue. You need to go to a mailing list or
    newsgroup that is specific to your OS and get them to help you figure out
    how to set the system timezone to be correct, and what mousey-clicky things
    you need to do to make that happen.

    --
    Brad Knowles,

    "They that can give up essential liberty to obtain a little temporary
    safety deserve neither liberty nor safety."
    -Benjamin Franklin, Historical Review of Pennsylvania.

    SAGE member since 1995. See for more info.

  3. Re: utc date set back to cdt by ntpd

    wrote in message
    news:20040712164742.676$AU@newsreader.com...
    > "Beemer Biker" wrote:
    >
    > > I "inherited" a standalone network with a linux box and a trimble GPS
    > > with the trimble driver setting the system clock and using that 1pps

    time
    > > signal. IANE, but I installed ntpd and set it to think it was a stratum
    > > 1. If I type "date" I see UTC time which is what I want. Now I want
    > > the other non-trible boxes to use my UTC time to sync. Currently they
    > > are all CDT (central time zone).

    >
    > Whether or not your time is synchronized properly has absolutely nothing

    to
    > do with what timezone your machines think they are in. If it did, then

    you
    > couldn't use NTP time servers around the world to help set your time
    > correctly on your local server.
    >
    > As far as servers are concerned, everything is done relative to UTC. It's
    > simply a display matter as to whether or not they show the time as
    > converted to EST5EDT, CEST, or whatever.
    >


    found how to set timezone in linux via a link from localtime to
    /usr/share/zoneinfo/UTC, it could not be done via the GUI.

    > Now, another factor is that you shouldn't set your stratum within the NTP
    > configuration. If you're using a GPS refclock and the GPS refclock driver
    > for it, your server should automatically set the refclock to Stratum 0,

    and
    > therefore it automatically becomes Stratum 1.
    >



    i have a program that sets the system clock from every trimble clock message
    and clears a hw counter that the 1pps signal increments. there is no
    refclock or driver for this and there are 4 identical systems. the 5th
    system has no trimble and only needs to be accurate to within 1 second of
    the other 5. This seems to be a kluge yes, i agree, and none of them would
    qualify aa real ntp server but for what we are doing it works fine. If i
    knew more about ntp and had more time I could implement (or find) a driver
    that would make each of the systems a true ntp server.

    For some reason starting and stopping the ntpd on the linux box generates
    (for the next 60 seconds or so) the following error message from Dimension4
    (v) 5.0: "The SNTP message received from the server indicates that the
    server is in an alarm sate and should not be used to synchronize other
    computers at this time. Will try again in a moment" After about 60 seconds
    or so I do get the time sync. Can this be speeded up? I get this message
    even if there is only 1 time server.

    ...thanks..


    > > On my other linux boxes i set up ntpd to use that server. They all have
    > > CDT instead of GPS even after syncing to the server. When I bring up
    > > redhat-config-date I cannnot advance the CDT to UTC unless I take the
    > > check off the "Enable Network Time Protocol". I can then set it up to
    > > UTC and the system clock advances by the 5 hours as it should. Putting
    > > the [x] back into "Enable Network Time Protocol" causes the time to go
    > > back to CDT as soon as the time is synced. The other dialog box "Time
    > > Zone" has a checkbox for [x] "System clock uses UTC" Putting or

    removing
    > > the "x" makes no difference. Anyway, I cannot get the UTC to stick as
    > > everytime I dismiss the Date/Time property box, the timesync reverts me
    > > to CDT.

    >
    > This is an OS/user interface issue. You need to go to a mailing list or
    > newsgroup that is specific to your OS and get them to help you figure out
    > how to set the system timezone to be correct, and what mousey-clicky

    things
    > you need to do to make that happen.
    >
    > --
    > Brad Knowles,
    >
    > "They that can give up essential liberty to obtain a little temporary
    > safety deserve neither liberty nor safety."
    > -Benjamin Franklin, Historical Review of Pennsylvania.
    >
    > SAGE member since 1995. See for more info.




  4. Re: utc date set back to cdt by ntpd

    "Beemer Biker" wrote:

    > i have a program that sets the system clock from every trimble clock
    > message and clears a hw counter that the 1pps signal increments.


    Trimble? Is this a GPS? If so, and the output is NMEA compliant, I'm sure
    you can get a working refclock.

    > For some reason starting and stopping the ntpd on the linux box
    > generates (for the next 60 seconds or so) the following error message
    > from Dimension4 (v) 5.0: "The SNTP message received from the server
    > indicates that the server is in an alarm sate and should not be used to
    > synchronize other computers at this time. Will try again in a moment"
    > After about 60 seconds or so I do get the time sync. Can this be speeded
    > up? I get this message even if there is only 1 time server.


    An SNTP client? You'd need to talk to the vendor for that.

    You can speed up the sync of the ntpd server somewhat by using "iburst" in
    your "server" lines in the /etc/ntp.conf, and by starting ntpd up with the
    "-g" option on the command line. With upstream clocks on the LAN, this
    should sync within 15-20 seconds or so.

    --
    Brad Knowles,

    "They that can give up essential liberty to obtain a little temporary
    safety deserve neither liberty nor safety."
    -Benjamin Franklin, Historical Review of Pennsylvania.

    SAGE member since 1995. See for more info.

  5. [off topic] Re: utc date set back to cdt by ntpd


    > found how to set timezone in linux via a link from localtime to
    > /usr/share/zoneinfo/UTC, it could not be done via the GUI.


    This method does not work properly if /usr is on a different filesystem
    (specifically, your system will drift at each reboot by increments of the
    time difference between your time zone and UTC if your battery-backed PC
    clock is on local time). Copying the file works in that case.

    In any case, Unix and ntp only care about UTC time internally, so the time
    zones are really off topic for ntp configuration.

  6. Re: [off topic] Re: utc date set back to cdt by ntpd

    David Monniaux wrote:
    > > found how to set timezone in linux via a link from localtime to
    > > /usr/share/zoneinfo/UTC, it could not be done via the GUI.

    >
    > This method does not work properly if /usr is on a different filesystem
    > (specifically, your system will drift at each reboot by increments of the
    > time difference between your time zone and UTC if your battery-backed PC
    > clock is on local time). Copying the file works in that case.


    Actually, best would be to create a symbolic link.

    --
    Brad Knowles,

    "They that can give up essential liberty to obtain a little temporary
    safety deserve neither liberty nor safety."
    -Benjamin Franklin, Historical Review of Pennsylvania.

    SAGE member since 1995. See for more info.

+ Reply to Thread