Symptoms
When there is a connectivity issue while reaching an NTP server from an ESXi host, the system clockon the ESXi host might experience a significant drift.Upon executing the vsish command vsish -e get /system/ntpclock/clockData, a large negative value is recorded in the adjtime field.NTP clock data { Clock state:0 Clock status:0x00002001 TAI offset:0 Maximum error (usec):655420 Estimated error (usec):349 Poll shift:6 Time offset (nsec):-143603 Freq offset (nsec/sec):12888 adjtime() (usec):-309237290312 <<<<<< tick adjustment (nsec/sec):-4987251 Ref timer freq (cycles/sec):2399998000
Cause
Known issue on ESXi 7.0 U3 and later.
Impact / Risks
Failure to synchronize with the NTP server due to loss of connectivity leads to time drift on ESXi hosts. If the connectivity issue is temporary and subsequently resolved, time drift will be corrected eventually.
Resolution
VMware is aware of this issue and working to resolve this in a future release.
Workaround
To address this issue, one of the following workarounds can be implemented:
Restore connectivity to the NTP server.Reset the ESXi clock state using the following command:
vsish -e set /system/ntpclock/clockData 1 Verify that the correct value has been set in the adjtime() function by executing the following command:
vsish -e get /system/ntpclock/clockData NTP clock data { Clock state:0 Clock status:0x00000040 TAI offset:0 Maximum error (usec):503000 Estimated error (usec):500000 Poll shift:3 Time offset (nsec):0 Freq offset (nsec/sec):0 adjtime() (usec):0 <<<<< tick adjustment (nsec/sec):0 Ref timer freq (cycles/sec):2399998000 }
