Information
Sets the local time zone information so that the time displayed by the Firepower is more relevant to those who are viewing it.
Rationale:
Having a correct time set on a Cisco Firepower is important for two main reasons. The first reason is that digital certificates compare this time to the range defined by their Valid From and Valid To fields to define a specific validity period. The second reason is to have a relevant time stamps when logging information. Whether you are sending messages to a syslog server, sending messages to an SNMP monitoring station, or performing packet captures, time stamps have little usefulness if you cannot be certain of their accuracy.
Solution
Firepower Device Manager:
Use Device > System Settings > NTP to configure system time.
or
FMC:
Step 1 From the drop-down list under your user name, choose User Preferences.
Step 2 Click the Time Zone Preference tab.
Step 3 From the left list box, choose the continent or area that contains the time zone you want to use.
Step 4 From the right list box, choose the zone (city name) that corresponds with the time zone you want to use.
Step 5 Click Save.