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Switch Management
FILE LOCATION: C:\Users\gina\Desktop\Checkout_new\Dell Astute\User
Guide\Dell_Astute_SwitchManagement.fm
D E L L C O N F ID E N T IA L – P R E L IM I N A R Y 8 / 9 /1 6 - FO R PR O O F O N L Y
• If there is a tie in stratums, packets from servers defined on the device are
preferred to Anycast packets, which in turn are preferred to Broadcast
packets.
• If multiple servers pass the above criteria, then the server that sent the first
(earliest) time packet is chosen.
If a better server is discovered later, it is selected to be the “designated server”
at that time.
Polling
You can configure the system to acquire time information in the following
ways:
•
Enable polling
— Time information is requested every polling interval.
•
Do not enable polling
— Time information is received when the system is
brought up and every time that a topological change is made to the
Running Configuration file, for example when an SNTP Unicast server is
added.
This is configured by the user in the
On power up, when the switch sends a request and there is no reply, it issues
another request (three retries at most) after 20 seconds of waiting.
If no SNTP server is found, the process is invoked every “poll interval” (set in
the
page), and a management trap is triggered.
Authentication
You can require that SNTP servers be authenticated, although this is not
mandatory (see the
page).
MD5 (Message Digest 5) Authentication safeguards device synchronization
paths to SNTP servers. MD5 is an algorithm that produces a 128-bit hash
value. MD5 is a variation of MD4, and increases MD4 security.
MD5 both verifies the integrity of the communication and authenticates the
origin of the communication.
SNTP Global Settings
If
SNTP
was selected as the clock source in the
page,
you must define the mechanism of setting time from an SNTP server. This is
done in the
pages, described below.
