H3C SOHO IE4300, Command Reference Manual

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maxpoll maxpoll-interval
: Specifies the maximum polling interval. The value range for the
maxpoll-interval
argument is 4 to 17, to which base 2 is raised to get the interval in seconds.
The maximum polling interval is in the range of 2
4
to 2
17
(16 to 131072) seconds. The default value
for the
maxpoll-interval
argument is 6 and the default maximum polling interval is 2
6
(64)
seconds.
minpoll minpoll-interval
: Specifies the minimum polling interval. The value range for the
minpoll-interval argument is 4 to 17, to which base 2 is raised to get the interval in seconds.
The minimum polling interval is in the range of 2
4
to 2
17
(16 to 131072) seconds. The default value for
the minpoll-interval argument is 6 and the default minimum polling interval is 2
6
(64) seconds.
priority
: Specifies this NTP server as the first choice under the same condition.
source interface-type interface-number
: Specifies the source interface for IPv6 NTP
messages. If the specified IPv6 NTP server address is not a link local address, the source IPv6
address for IPv6 NTP messages sent by the local device to the NTP server is the IPv6 address of the
specified source interface. If the specified IPv6 NTP server address is a link local address, the IPv6
NTP messages are sent from the specified source interface, and the source address of the
messages is the link local address of the interface. The
interface-type interface-number
argument represents the interface type and number. If you do not specify an interface, the device
automatically selects the source IPv6 address of IPv6 NTP messages. For more information, see
RFC 3484 .
Usage guidelines
When you specify an IPv6 NTP server for the device, the device is synchronized to the IPv6 NTP
server, but the IPv6 NTP server is not synchronized to the device.
To synchronize the PE to a PE or CE in a VPN instance, specify the
vpn-instance
vpn-instance-name
option in the command.
If you include the vpn-instance vpn-instance-name option in the undo ntp-service
unicast-server
command, the command removes the NTP server in the specified VPN. If you
do not include the
vpn-instance vpn-instance-name
option in the command, the command
removes the NTP server on the public network.
If the specified IPv6 address of the NTP server is a link local address, you must specify the source
interface for NTP messages and cannot specify a VPN instance for the NTP server.
After you specify an IPv6 NTP server for a device, the device polls and synchronizes its time with the
server at the minimum polling interval. If the time discrepancy between the two remains in the
acceptable range, the system gradually increases the polling interval until the maximum polling
interval is reached. If the time discrepancy exceeds the acceptable range repeatedly, the polling
interval decreases gradually.
The polling interval configuration takes effect when the next polling starts.
Examples
# Specify the IPv6 NTP server 2001::1 for the device.
<Sysname> system-view
[Sysname] ntp-service ipv6 unicast-server 2001::1
Related commands
ntp-service authentication enable
ntp-service authentication-keyid
ntp-service reliable authentication-keyid