In my lab I’ve had some issues with my vRealize Automation (vRA) / vCloud Automation Center (vCAC) appliances not having the correct time even though time was configured in the appliance admin pages. I was able to get the time to be consistently correct by creating a cron job on each of the appliances. Here is the process for creating a cron entry to sync the appliance’s time with an external time server.
1) ssh or open a console to the appliance. Login as root.
2) Open the crontab for root: crontab -e
When you run the crontab command on the appliances it launches the VI editor. If you need more info on VI, you can search for it. Here is a cheatsheet: http://www.albany.edu/faculty/hy973732/ist535/vi_editor_commands.pdf
3) Enter insert mode by entering a lower case i
4) Paste in the following or add to the existing entries:
# ------------- minute (0 - 59) # | ----------- hour (0 - 23) # | | --------- day of month (1 - 31) # | | | ------- month (1 - 12) # | | | | ----- day of week (0 - 6) (Sunday=0) # | | | | | */5 * * * * /usr/sbin/sntp -P no -r 192.168.1.254
5) Save the file by pressing escape :wq <enter> or escape ZZ
*/5 means to update the time every 5 minutes and 192.168.1.254 is my time server.
You can find more about the sntp command at http://www.tutorialspoint.com/unix_commands/sntp.htm