Masterclock GMR5000 - NTP and Timekeeping Troubleshooting; Problem: NTP;SNTP Client Communication Failure; Problem: Invalid or Flagged NTP Time; Problem: Incorrect Time or Loss of Retention

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MasterclockGMRUserManualv2–2016.12
66
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PROBLEM:
 NTP/SNTPclientisunabletocommunicatewiththeGMR.
POSSIBLEREASONS/SOLUTIONS:
1. VerifythattheGMRisattachedtothenetwork.
2. Verifythatallnetworkcables,hubs,etc.areinproperworkingorder.BesurethatEthernetcrossovercables
arenotbeingusedwhereinappropriate.
3. VerifythattheGMRisactuallyreachablefromtheclient.Try“pinging”theIPaddress
oftheGMR.Ifthisfails,
itispossiblethatithasaninvalidnetworkconfigurationorthatthenetworkisdown.Consultyournetwork
administratorforassistance.
4. VerifythattheGMRissettooutputifoperatingininternaloscillator/realtimeclockmodeandthatthe
maximumtime
differencehasnotbeenexceeded.
5. Verifythattheclientisnotusing“SymmetricActive”mode.TheGMRdoesnotuseAuthenticationandwillnot
workwithNTP/SNTPclientsina“SymmetricActive”mode.
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PROBLEM:
 TheNTPclientindicatesthattheGMRisprovidinginvalidtime,orhasflaggedtimeasinvalid.
POSSIBLEREASONS/SOLUTIONS:
1. TheGMRwillalwaysanswerNTPrequests(unlesstheclientissettousesymmetricactivemode).TheGMR
willflagtimeasinvalidifitdoesnothavetrustedtimetodistribute.ThismayoccurtemporarilyduringGPS
navigationstatechangesorbeforethefirstGPSacquisitionduringpower
upfollowingalongperiodwithout
power.
2. Bydefault,theGMRwillbeginflaggingtimeinvalidafter24hoursofconsecutiveGPSacquisitionfailureor
non‐operation(i.e.poweroff).Thisisaprotectivefeature.Itcanbeadjustedordisabledifdesired.
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PROBLEM:
 TheUTCdateandtimeareincorrectandtheGMRdoesnotretaintimesettingswhenpowereddownorup.
POSSIBLEREASONS/SOLUTIONS:
TheGMRmaintainsitsinternaltimeinbattery‐backedmemorylocatedusingaReal‐TimeClock(RTC).Thebattery
suppliespower,upto24hours,totheTCXO32kHzoscillatorandRTCwhentheunitispoweredoff.Thisallowsthe
internalconfigurationtobemaintainedandthetimeanddate
tocontinuetoincrement.So,ifthereisaproblem
here,theinternalbatterylikelyneedsreplacement.
Thebatterytypeisa“maintenancefree”3Vrechargeablemagnesiumlithiumbattery.Itcanbereplacedbya
qualifiedtechnician.OrtheunitcanbesenttotechnicalsupportatMasterclock.
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PROBLEM:
 Lostpassword.
POSSIBLEREASONS/SOLUTIONS:
Yourcustompasswordcannotberecoveredifitislost.ResettheGMRtothefactorydefaultconfiguration.Under
factorydefaultstheGMRwillneedtobereconfiguredtoyourcustomsettings.