Server and Clients Time out of sync

Discussion in 'Mac OS X Server, Xserve, and Networking' started by benny gsr, Feb 19, 2017.

  1. benny gsr macrumors newbie

    Joined:
    Nov 27, 2015
    Location:
    Australia
    #1
    HI,

    We run a medical software across a network of computers. The server holds the server software and the clients all run clients versions of software.

    Hardware:
    Mac Mini quad core for server with sad
    Mac mini i5's for clients.
    Software
    Malpractice

    We have had numerous issues and Macpractice are stumped. When running in AUTO time selection settings on each computer, we think we have it narrowed down to the machines clocks in system preferences falling out of sync.

    I thought by setting times on each manually, and as closed to synced as possible that should solve it, but have found the server jumping ahead by 15 seconds in a weekend. This seems to corrupt server to client connection and there are certain functions we can't complete with our software.

    My IT guy hasn't seen this before, and I'm looking for more info.
    Any advice would be appreciated.
     
  2. satcomer macrumors 603

    satcomer

    Joined:
    Feb 19, 2008
    Location:
    The Finger Lakes Region
    #2
    In the Server what DNS Server is it connecting to?
     
  3. belvdr macrumors 603

    Joined:
    Aug 15, 2005
    #3
    Implement NTP:

    1. Set the NTP client on the server to point to something like pool.ntp.org
    2. Set the NTP client on each client to point to the server
    You could also point every system at pool.ntp.org, but then you have unnecessary traffic going to the Internet. It's much cleaner to do the above.

    Without NTP, each client drifts on its own with no correction.
     
  4. benny gsr thread starter macrumors newbie

    Joined:
    Nov 27, 2015
    Location:
    Australia
    #4
    The DNS - I am using some sort of open DNS that I got told to send to by the Macpractice people.
    203.161.169.200

    Your post got me wondering if I should perhaps just use my router? We have only 5 client machines, but I've been told different things about whether to use the router for DNS?

    You may have already gathered I'm a real novice with troubleshooting networking stuff, but the NTP server, trying to set that up might be beyond my scope.

    I can follow pretty detailed instructions, but if something goes wrong, I wouldn't know how to fix it.

    Additionally my IT guy has said he hasn't set up NTP servers, so said he couldn't help me there.
     
  5. belvdr macrumors 603

    Joined:
    Aug 15, 2005
    #5
    NTP is not difficult. Most business routers can do this and Google might tell you how.

    Just take the easy way then, point all systems to get their time from the same source in System Preferences -> Date and Time.
     
  6. satcomer macrumors 603

    satcomer

    Joined:
    Feb 19, 2008
    Location:
    The Finger Lakes Region
    #6
    Point as secondary NTP server openDNS to IPs 208.67.222.222 and 208.67.220.220! You should always have to different NTP server points just in case!
     
  7. belvdr macrumors 603

    Joined:
    Aug 15, 2005
    #7
    If you use pool.ntp.org, it randomly rotates between servers, so you only need one entry:

    http://www.pool.ntp.org/en/use.html
     
  8. satcomer macrumors 603

    satcomer

    Joined:
    Feb 19, 2008
    Location:
    The Finger Lakes Region
    #8
    Any IT person will tell you at least two are needed in sever! So don't believe the hype and get caught just like when the 2012 Super Derecho knocked out Amazon, Netflix and Others when in went through Northern Virginia that evening then Diesel fuel went out! In whole area!

    So don't rely on marking promises!
     
  9. belvdr, Feb 26, 2017
    Last edited: Feb 26, 2017

    belvdr macrumors 603

    Joined:
    Aug 15, 2005
    #9
    In my 20 years of IT, I have never had an issue using my response. What you are referring to has nothing to do with NTP. Feel free to use more than one; it is listed in the article.

    Also if you setup NTP properly you have one master going to the Internet for time and all other systems report up that chain. For example, a router at a remote site can point to your local master and remote clients point to that router.
     
  10. benny gsr thread starter macrumors newbie

    Joined:
    Nov 27, 2015
    Location:
    Australia
    #10
    Thanks for the replies. A lot of what is being said is over my head. I am in the process of finding someone who can do this for me.
    In the meantime what I did was in system preferences, go to Date and Time and then type pool.ntp.org into the time server bar. Pressed enter and all the time synced. I did this on each machine as I don't know how to point the other machines to the server. They sync for about 12 hours, and progressively go out of sync again. Over about 72 hours last weekend, the time got out to about 8 seconds! Then, when I enter date and time again, press enter, the clock on the machines (the server I think) then sets itself the 8 seconds back or forward again.
    There is something wrong here, but I have no idea what.

    The following photo shows the time of the server (left image in screen sharing) and a client machine about 14 hours after I re-synced (pressed Enter each time in the text bar)
    Screen Shot 2017-02-28 at 8.36.23 AM.png
     

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