The Lantronix Control Center and Local Managers rely on NTP to keep their clocks in sync. This keeps timestamps on alarms and events correct and ensure scheduled jobs and monitors run at the right time. If the UCC and LMs are not synchronized, the following alarm will be generated on the Local Manager:
System and management server clocks are more than 20 seconds out of syncControl Centers should arrive with their clocks already synchronized to UTC time. Changing to another time zone (or moving the time too far ahead/back) may cause the application to fail.
Do not alter the Control Center's time zone.Part of the Control Center's setup involves pointing it at a valid NTP server. This should keep the clock in sync automatically. However, NTP settings can be configured outside of the setup script if they need to be updated.
Please choose the instructions that match your version of software.
Log into the UCC and become root.
In CentOS 8, ntp has been replaced with chrony
Use vi to edit /etc/chrony.conf.
[root@LantronixControlCenter ~]# vi /etc/chrony.confLook for a line that says server, similar to:
server pool.ntp.org iburstIf that line doesn't exist, you can add it to the end of the configuration file.
Press the "I" key to enter Insert mode. Replace or add your NTP server IP address or hostname after the server command.
server 10.10.10.22 iburstPress ESC, then type :wq to save the file.
Stop the chronyd service.
[root@vUCC ~]# systemctl stop chronyd.serviceUse the chronyd command to synchronize the time.
[root@vUCC ~]# chronyd -q 'server pool.ntp.org iburst'
2021-02-11T16:44:19Z chronyd version 3.5 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SIGND +ASYNCDNS +SECHASH +IPV6 +DEBUG)
2021-02-11T16:44:19Z Initial frequency -13.140 ppm
2021-02-11T16:44:24Z System clock wrong by 0.001404 seconds (step)
2021-02-11T16:44:24Z chronyd exitingStart the chronyd service.
[root@vUCC ~]# systemctl start chronyd.serviceYou can use the chronyc sources command to check the status of NTP synchronization.
[root@vUCC ~]# chronyc sources
210 Number of sources = 2
MS Name/IP address Stratum Poll Reach LastRx Last sample
===============================================================================
^- 127.127.1.0 5 6 177 50 +3052ns[+3052ns] +/- 243ms
^* 157.119.108.165 4 6 177 55 -873us[-1155us] +/- 242msYou can use the chronyc clients command to view the status of incoming queries.
[root@vUCC-Eval ~]# chronyc clients
Hostname NTP Drop Int IntL Last Cmd Drop Int Last
===============================================================================
localhost.localdomain 14 0 6 - 64 0 0 - -
172.30.5.47 9 0 2 - 9 0 0 - -As with all OS-level configuration, you must first log into the UCC via SSH or console and become root.
Use vi to open the /etc/ntp.conf file.
[root@LantronixControlCenter ~]# vi /etc/ntp.confPress the "I" key to enter Insert mode. Add the following lines to /etc/ntp.conf, substituting your NTP server's IP address or hostname (if DNS is configured).
server 203.0.113.201
restrict 203.0.113.201If you have not previously run the netSetup.sh script, the "server" line may be missing. Simply add it above "restrict."
Press ESC, then type :wq to save the file.
If you are not using NTP Authentication, you can skip to Sync the UCC's time
If your NTP server requires authentication through a pre-shared secret, additional configuration is required.
Use vi to open the /etc/ntp.conf file.
[root@LantronixControlCenter ~]# vi /etc/ntp.confPress the "I" key to enter Insert mode. Modify the "server" and "restrict" lines to match the following syntax, substituting your NTP server's IP. Add the "keys" and "trusted" lines as well.
server 203.0.113.201 key 1
restrict 203.0.113.201 notrust
keys /etc/ntp.keys
trustedkey 1Press ESC, then type :wq to save the file.
Use vi to create/open the /etc/ntp.keys file.
[root@LantronixControlCenter ~]# vi /etc/ntp.keysPress the "I" key to enter Insert mode. Add the following line, substituting your pre-shared secret.
1 M my-preshared-secret1 specifies the key number. You may have to add multiple keys if you use more than one NTP server and if each has its own key.
M specifies an MD5 pre-shared secret.
my-preshared-secret can be any word between 1 and 31 characters. It cannot contain any of the following characters:
(space), #, \t, \n, \0To ensure only ntp process and root user can read/edit the file, run the following commands:
[root@LantronixControlCenter ~]# chmod 640 /etc/ntp.keys
[root@LantronixControlCenter ~]# chown root:ntp /etc/ntp.keys
[root@LantronixControlCenter ~]# ls -al /etc/ntp.keys
-rw-r----- 1 root ntp 12 Jan 25 14:01 /etc/ntp.keysStop the ntpd service.
[root@LantronixControlCenter ~]# service ntpd stop
Shutting down ntpd: [ OK ]Use the ntpdate command to synchronize the time.
[root@LantronixControlCenter ~]# ntpdate 192.51.100.1
18 Nov 18:29:38 ntpdate[11892]: step time server 192.51.100.1 offset -1.502414 secStart the ntpd service.
[root@LantronixControlCenter ~]# service ntpd start
Starting ntpd: [ OK ]You can use the ntpq command to check the status of NTP synchronization.
[root@LantronixControlCenter ~]# ntpq -pc asHere's an example that failed because the server doesn't authenticate its packets.
remote refid st t when poll reach delay offset jitter
==============================================================================
203.0.113.201 .RSTR. 16 u - 64 0 0.000 0.000 4000.00
ind assID status conf reach auth condition last_event cnt
===========================================================
1 65044 c000 yes yes bad rejectHere's an example that passes authentication, but just needs a little more time before it has reliable jitter numbers and will sync the time.
remote refid st t when poll reach delay offset jitter
==============================================================================
198.51. 100.1 198.51.100.254 6 u 23 64 7 0.378 -8524.2 20934.8
ind assID status conf reach auth condition last_event cnt
===========================================================
1 43013 f014 yes yes ok reject reachable 1Here, the NTP server passes authentication and is syncing the time.
remote refid st t when poll reach delay offset jitter
==============================================================================
*198.51. 100.1 198.51.100.254 6 u 28 64 377 0.201 0.296 0.068
ind assID status conf reach auth condition last_event cnt
===========================================================
1 56140 f614 yes yes ok sys.peer reachable 1If the output from ntpq does not match one of the examples, further troubleshooting may be necessary.
To test ntp auth with ntpdate run the following:
[root@LantronixControlCenter ~]# ntpdate -d -a 1 -k /etc/ntp/ntp.keys 203.0.113.201To debug a potentially bad configuration file, stop ntpd, and run it in the foreground with the following commands (as root):
[root@LantronixControlCenter ~]# service ntpd stop
Shutting down ntpd: [ OK ]
[root@LantronixControlCenter ~]# ntpd -u ntp:ntp -d
ntpd 4.2.6p5@1.2349-o Tue Jan 1 10:09:21 UTC 2016 (1)
22 Jan 02:41:24 ntpd[29666]: proto: precision = 0.067 usec
22 Jan 02:41:24 ntpd[29666]: 0.0.0.0 c01d 0d kern kernel time sync enabled
event at 0 0.0.0.0 c01d 0d kern kernel time sync enabled
Finished Parsing!!
restrict: op 1 addr 0.0.0.0 mask 0.0.0.0 mflags 00000000 flags 000005d0
restrict: op 1 addr :: mask 0.0.0.0 mflags 00000000 flags 000005d0
restrict: op 1 addr :: mask :: mflags 00000000 flags 000005d0
restrict: op 1 addr 127.0.0.1 mask 255.255.255.255 mflags 00000000 flags 00000000
restrict: op 1 addr 198.51.100.60 mask 255.255.255.255 mflags 00000000 flags 00000004
22 Jan 02:41:24 ntpd[29666]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16
22 Jan 02:41:24 ntpd[29666]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123
22 Jan 02:41:24 ntpd[29666]: Listen and drop on 1 v6wildcard :: UDP 123
22 Jan 02:41:24 ntpd[29666]: Listen normally on 2 lo 127.0.0.1 UDP 123
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