Troubleshooting Time Zone Configuration

Processes use different time zones

Processes on FreeBSD (and thus pfSense® software) only pick up time changes when they are started. If the firewall has not been rebooted since the last time zone change, doing so will ensure that all running processes are using the correct time zone.

Clock does not use the expected zone offset

If the clock is several hours off, but accurate to the minute, it is most likely a time zone setting issue. If using a GMT offset time (e.g. -0500), change to a more specific geographic time zone such as America/New_York instead.

Using geographic zones is the best practice as they use an accurate offset, include local Daylight Saving Time behavior, and also consider historical changes in time zones.

The following text from the time zone database explains the behavior of the GMT zones further:

# We use POSIX-style signs in the Zone names and the output abbreviations,
# even though this is the opposite of what many people expect.
# POSIX has positive signs west of Greenwich, but many people expect
# positive signs east of Greenwich.  For example, TZ='Etc/GMT+4' uses
# the abbreviation "GMT+4" and corresponds to 4 hours behind UTC
# (i.e. west of Greenwich) even though many people would expect it to
# mean 4 hours ahead of UTC (i.e. east of Greenwich).

This behavior is also noted on the Wikipedia page for the time zone database.