Brocade VDX 8770-8 Hardware Reference Manual - Manual (Page 55)

Brocade VDX 8770-8 Hardware Reference Manual 35
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Setting the date and time
3
Setting the date and time
The MM maintains 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 Brocade VDX 8770-8 with an incorrect date and time value functions properly. Because the date
and time are used for logging, error detection, and troubleshooting, you should set them correctly.
Time zones
You can set the time zone for a switch by using the clock timezone command. The time zone setting
has the following characteristics:
• The time zone 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 Network Time Protocol (NTP) server synchronization.
The following regions are supported: Africa, America, Arctic, Antarctica, Asia, Atlantic, Australia,
Europe, Indian, and Pacific. One of these, along with a city name, establishes the time zone. Refer
to
“Setting the time zone.”
Time synchronization
To keep the time in your network current, it is recommended that each switch has its time
synchronized with at least one external NTP server.
All switches in the fabric maintain the current clock server value in nonvolatile memory. By default,
this value is the local switch clock.
The ntp server command accepts multiple server addresses in either IPv4 or IPv6 format. When
multiple NTP server addresses are passed, ntp server sets the first obtainable address as the
active NTP server. If there are no reachable time servers, then the local switch time is the default
time.
Synchronizing local time using NTP
Perform the following steps to synchronize the local time using NTP.
1. Log on to the switch using the admin account (the default password is password).
2. Enter configure terminal to change to global configuration mode.
switch# configure terminal
Entering configuration mode terminal