I am having an External NTP server, Which is tagged to my CVM, unfortunately my AHV is not corresponding with mt NTP server even it is reachable from my hypervisor level. I have checked my Hypervisor thru ssh and run the command ‘date’ its gives me different time from my NTP server.
Solved
NTP Time In AHV And CVM is not Synchronizing
Best answer by HITESH0801
Hello
If the sync with an external NTP server is broken, there are chances of time-drift.
The following NCC Health check will FAIL if there is a time drift or some issue with NTP.
NCC Health Check: check_ntp
The following KB mentions the impact of the check failure on the environment
NCC Health Check: check NTP KB
This topic has been closed for comments
+2- Nutanix Employee
- 23 replies
Hey
Did you take a look at the NTP troubleshooting article?
https://support-portal.nutanix.com/#/page/kbs/details?targetId=kA032000000bmjeCAA
See if this article helps you.
Regards,
Shaurya Bhardwaj
Oh hi there thanks!
i just opened a support and found out that my NTP server is using its local time, i think i just need to configure my NTP server to synchronize with reliable time source. Thanks again! :)
1 person likes this
+5- Nutanix Employee
- 104 replies
Hello
Glad that the problem was isolated.
You can use the following document to configure NTP in Prism and know the guidelines and best practises of configuring NTP.
Hello
I have a question, If the Nutanix cluster is connected directly to External Time Source(Public NTP server), What will happen if the the Internet suddenly went down? Does it affects my CVM,Hypervisor, and VM’s?
Thank you!
+5- Nutanix Employee
- 104 replies
- Answer
Hello
If the sync with an external NTP server is broken, there are chances of time-drift.
The following NCC Health check will FAIL if there is a time drift or some issue with NTP.
NCC Health Check: check_ntp
The following KB mentions the impact of the check failure on the environment
NCC Health Check: check NTP KB
+4- Nutanix Employee
- 77 replies
If you look at CVM time synchronization across the cluster, i.e. “allssh ntpq -pn” you’ll see that one CVM is set to sync from outside the cluster and all other CVMs will sync to this CVM. So long as CVMs are in sync with eachother there should not be a disruption to data service but some impact could be seen.
As you likely know, any domain authentication using Kerberos can only suffer a 5 minute time discrepancy, so if CVM time drifted 5+ minutes from AD server time, LDAP authentication with the AD domain would fail. This is particularly troublesome if using a Hyper-V cluster and Kerberos authentication is configured for file access. In that case failing authentication could cause data service disruption. This is one reason I always recommended to sync to the same sources as your AD domain controller.
Significant time discrepancy between the CVM cluster and Prism Central, or between different CVM clusters which are paired as remote sites for Async DR replication can also cause some issues, but impact would be isolated cluster management from Prism Central, or in the case of the remote site setup you could see issue with remote replication or DR operations. In either case, local operation of the cluster is not impacted but sync relationships with the remote system could be impacted.
If the CVM time runs ahead, you can work with Nutanix support to correct the time discrepancy.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.