Chapter 5
Setup and Configuration
RUGGEDCOM ROX II
User Guide
278
Managing Time Synchronization Functions
2
3
1
Figure 287: SNMP Group Access Configuration Table
1.
Add Button
2.
Edit Button
3.
Delete Button
3. Click
Delete
next to the chosen group.
4. Click
Commit
to save the changes or click
Revert All
to abort. A confirmation dialog box appears. Click
OK
to proceed.
5. Click
Exit Transaction
or continue making changes.
Section 5.12
Managing Time Synchronization Functions
ROX II uses version 4 of the Network Time Protocol (NTP) to synchronize the internal clock with a time source.
NOTE
For more information about version 4 of NTP, refer to
[http://tools.ietf.org/html/rfc5905].
NTP is a fault-tolerant protocol that allows an NTP daemon to automatically select the best of several available
reference clocks to synchronize with. Multiple candidates can be combined to minimize the accumulated error.
The NTP daemon can also detect and avoid reference clocks that are temporarily or permanently advertising the
wrong time.
The NTP daemon achieves synchronization by making small and frequent changes to the internal clock. It
operates in a
client-server
mode, which allows it to synchronize the internal clock with NTP servers and act as an
NTP server for peer devices.
If multiple NTP servers are available to choose from, the NTP daemon will synchronize with the server that has
the lowest stratum. The stratum is a rating of the server compared to the server with the reference clock. The
reference clock itself appears at stratum 0. A server synchronized with a stratum
n
server will be running at
stratum
n+1
.
NTP hosts with a lower stratum are typically configured as NTP servers, while NTP hosts with higher stratums
are configured at the same stratum as their peers. If each NTP server fails, a configured peer will help in
providing the NTP time. It is recommended that at least one server and one peer be configured.
The NTP daemon knows which NTP servers and peers to use in three ways:
• The daemon is configured manually with list of servers to poll
Summary of Contents for RUGGEDCOM RX1510
Page 32: ...RUGGEDCOM ROX II User Guide Preface Customer Support xxxii ...
Page 44: ...RUGGEDCOM ROX II User Guide Chapter 1 Introduction User Permissions 12 ...
Page 62: ...RUGGEDCOM ROX II User Guide Chapter 2 Using ROX II Using the Command Line Interface 30 ...
Page 268: ...RUGGEDCOM ROX II User Guide Chapter 4 System Administration Deleting a Scheduled Job 236 ...