Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 97)

Using Network Time Protocol
● Network Time Protocol overview.....................................................................................97
● Configuring NTP..............................................................................................................98
Network Time Protocol overview
Network Time Protocol (NTP) maintains uniform time across all switches in a network. The NTP
commands support the configuration of an external time server to maintain synchronization between all
local clocks in a network.
To keep the time in your network current, it is recommended that each switch have its time
synchronized with at least one external NTP server. External NTP servers should be synchronized
among themselves in order to maintain fabric-wide time synchronization.
All switches in the fabric maintain the current clock server value in nonvolatile memory. By default, this
value is the local clock server of the switch.
Date and time settings
Brocade switches maintain the current date and time inside a battery-backed real-time clock (RTC)
circuit. Date and time are used for logging events. Switch operation does not depend on the date and
time; a switch with incorrect date and time settings can function correctly. However, because the date
and time are used for logging, error detection, and troubleshooting, you should set them correctly.
Time zone settings
You can set the time zone by specifying a geographic region and city by name. You can choose one of
the following the regions: Africa, America, Pacific, Europe, Antarctica, Arctic, Asia, Australia, Atlantic,
and Indian.
The time zone setting has the following characteristics:
• The setting automatically adjusts for Daylight Savings Time.
• Changing the time zone on a switch updates the local time zone setup and is reflected in local time
calculations.
• By default, all switches are in the Greenwich Mean Time (GMT) time zone (0,0). If all switches in a
fabric are in one time zone, it is possible for you to keep the time zone setup at the default setting.
• System services that have already started will reflect the time zone changes only after the next
reboot.
• Time zone settings persist across failover for high availability.
• Time zone settings are not affected by NTP server synchronization.
Network OS Administrator’s Guide 97
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