Brocade 6520 Hardware Reference Manual - Manual (Page 25)

Brocade 6520 Hardware Reference Manual 13
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Brocade 6520 configuration
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If the time zone is not set with the new options, the switch retains the offset time zone settings. The
tsTimeZone command includes an option to revert to the prior time zone format. For more
information about the
--
old option, refer to the Fabric OS Command Reference.
You can set the time zone for a switch using the tsTimeZone command. The tsTimeZone command
allows you to perform the following tasks:
• Display all of the time zones supported in the firmware
• Set the time zone based on a country and city combination or based on a time zone ID such as
PST
The time zone setting has the following characteristics:
• You can view the time zone settings. However, only those with administrative permissions can
set the time zones.
• The tsTimeZone 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.
Local time synchronization
You can synchronize the local time of the principal or primary fabric configuration server (FCS)
switch to a maximum of eight external Network Time Protocol (NTP) servers. To keep the time in
your SAN current, it is recommended that the principal or primary FCS switch has its time
synchronized with at least one external NTP server. The other switches in the fabric will
automatically take their time from the principal or primary FCS switch.
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 principal or primary FCS switch. Changes to the clock
server value on the principal or primary FCS switch are propagated to all switches in the fabric.
When a new switch enters the fabric, the time server daemon of the principal or primary FCS switch
sends out the addresses of all existing clock servers and the time to the new switch. If a switch with
Fabric OS 5.3.0 or later has entered the fabric, it will be able to store the list and the active servers;
pre-Fabric OS 5.3.0 switches will ignore the new list parameter in the payload and will update only
the active server address.
If the active NTP server configured is IPv6, then distributing the same information in the fabric will
not be possible to switches earlier than Fabric OS 5.3.0 because IPv6 is supported for Fabric OS
5.3.0 and later. The default value LOCL will be distributed to pre-Fabric OS 5.3.0 switches.
The tsClockServer command accepts multiple server addresses in IPv4, IPv6, or DNS name
formats. When multiple NTP server addresses are passed, tsClockServer sets the first obtainable
address as the active NTP server. The rest are stored as backup servers that can take over if the
active NTP server fails. The principal or primary FCS switch synchronizes its time with the NTP
server every 64 seconds.