On the command line guide you won't see any downtime requirements for the Unity Connection server:
Command Line Interface Reference Guide for Cisco Unified Communications Solutions Release 8.5(1)
Utils ntp restart
This command restarts the NTP service.
utils ntp restart
Command privilege level: 0
Allowed during upgrade: Yes
Also on the caveats i do not see any particular mention for this: (Caveats could be found applicable to CUC)
Release Notes for Cisco Unified Communications Manager Release 8.5(1)
Breaking up the output of the "utils ntp status" there are are two considerations:
admin:utils ntp status
ntpd (pid 10899) is running...
remote refid st t when poll reach delay offset jitter
*127.127.1.0 LOCAL(0) 10 l 16 64 377 0.000 0.000 0.002
First, you are using the ip address 127.127.1.0 which is the referenced used for the local system clock, the asterisc means is the preferred option as there is no other IP available. This is not a good practice and not recommended.
Secondly the stratum is unreliable, meaning too high to reach or too low to be accepted by Unity Connection.
If you would happen to run 'utils diagnose test' you would have probably seen an output as the following example below:
admin:utils diagnose test
Log file: platform/log/diag1.log
Starting diagnostic test(s)
test - disk_space : Passed (available: 25680 MB, used: 7849 MB)
skip - disk_files : This module must be run directly and off hours
test - service_manager : Passed
test - tomcat : Passed
test - tomcat_deadlocks : Passed
test - tomcat_keystore : Passed
test - tomcat_connectors : Passed
test - tomcat_threads : Passed
test - tomcat_memory : Passed
test - tomcat_sessions : Passed
test - validate_network : Reverse DNS lookup missmatch
test - raid : Passed
test - system_info : Passed (Collected system information in diagnostic log)
test - ntp_reachability : Passed
test - ntp_clock_drift : Passed
test - ntp_stratum : Failed
The reference NTP server is a stratum 11 clock.
NTP servers with stratum 5 or worse clocks are deemed unreliable.
Please consider using an NTP server with better stratum level.
Please use OS Admin GUI to add/delete NTP servers.
skip - sdl_fragmentation : This module must be run directly and off hours
skip - sdi_fragmentation : This module must be run directly and off hours
test - ipv6_networking : Passed
And on the RTMT (Real Time Monitoring Tool) you would have seen a Critical event:
The best external NTP server, , is stratum , which is unacceptably high. External NTP servers must be <= strata 8 and should be <= strata 5. NTP server strata can be verified using the CLI 'utils ntp status' command ('st' column). Try using different NTP servers.
All specified external NTP server(s) have unacceptably high stratum values. Network issues exist or the designated servers have unreliable stratum values.
Information is self explanatory and therefore reassures the need of having a NTP different from the server itself.
By the snippet you sent we can know that it is the publisher server, as the Subscriber polls this information from the Publisher.
Installing the Operating System and Cisco Unity Connection 8.x
"Cisco recommends that you use an external NTP server to ensure accurate system time on the publisher server. Ensure the external NTP server is stratum 9 or higher (meaning stratums 1-9). The subscriber server will get its time from the publisher server"
Documentation also reaffirms the need for that NTP to be accessible otherwise your system can be degraded. Some addtional information which would be interesting to know is:
- Why did they had to restart the NTP in the first place?
System Requirements for Cisco Unity Connection Release 8.x
"A network time protocol (NTP) server must be accessible to the Connection server"
On the Cisco Unity Connection Serviceability> Tools> CLuster Management screen shot you sent i see that the ports were "Not Available" and that the customer stated "there was no service for 5 minutes".
By no service did they mean that over the phone they heard a disconnected tone or a failsafe message?
Additionaly after the servers resolved from SBR the Subscriber never recovered entirely as it did not start the Conversation Manager service.
Bottom line if they are able to reproduce it then it would be worth a while checking with TAC
David Rojas Peck
Cisco TAC Support Engineer, Unity
Mon, Wed, and Fri 12:00 pm to 9:00 pm ET, Tue and Thu 8:00 am to 5:00pm ET
Cisco Worldwide Contact link is below for further reference.