Manually Triggering A Time Synchronization - D-Link NetDefendOS User Manual

2. Enable Custom under Time synchronization
3. Now enter:
• Time Server Type: SNTP
• Primary Time Server: dns:ntp1.sp.se
• Secondary Time Server: dns:ntp2.sp.se
4. Click OK
The time server URLs must have the prefix dns: to specify that they should be resolved with a
DNS server. NetDefendOS must therefore also have a DNS server defined so this resolution can
be performed.
Example 2.25. Manually Triggering a Time Synchronization
Time synchronization can be manually triggered from the CLI. The output below shows a typical
response.
Command-Line Interface
gw-world:/> time -sync
Attempting to synchronize system time...
Server time: 2008-02-27 12:21:52 (UTC+00:00)
Local time: 2008-02-27 12:24:30 (UTC+00:00) (diff: 158)
Local time successfully changed to server time.
Maximum Time Adjustment
To avoid situations where a faulty time server causes the clock to be updated with an extremely
inaccurate time, a Maximum Adjustment value (in seconds) can be set. If the difference between
the current NetDefendOS time and the time received from a time server is greater than this
maximum adjustment value, then the time server response will be discarded.
For example, assume that the maximum adjustment value is set to 60 seconds and the current
NetDefendOS time is 16:42:35. If a time server responds with a time of 16:43:38 then the
difference is 63 seconds. This is greater than the maximum adjustment value so no update
occurs for this response.
Example 2.26. Modifying the Maximum Adjustment Value
In this example, The maximum adjustment value will be set to 40,000 seconds. This is the
maximum time difference that an external server is allowed to adjust for. There may be a valid
reason why there is a significant difference such as an incorrect NetDefendOS configuration.
Command-Line Interface
gw-world:/> set DateTime TimeSyncMaxAdjust=40000
Chapter 2: Management and Maintenance
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