Symmetricom Time Server - Manual (Page 125)

6000-100AppD.fm Rev. D TimeVault™ User’s Manual D-111
Symmetricom SNMP Enterprise MIB Appendix D: SNMP – Simple Network Management Protocol
The trap message group holds the ASCII string data to send whenever an SNMP trap
message is transmitted. The NTS agent sends SNMP trap messages to SNMP
management hosts notifying them of some critical event at the NTS agent. The NTS
issues three types of trap messages. The first type is a cold start trap message indicating
when the box boots or re-initializes. The second type of trap message is issued when the
NTS estimated time error has exceeded the minimum time accuracy threshold. The third
trap message is issued when a packet received by the NTS agent fails SNMP
authentication. The second feature notifies a network administrator immediately if the
time server lost its ability to tell accurate time.
The NTP Enterprise Group furnishes information on the Network Time Protocol. This
group provides packet information for the number of received, rejected, and transmitted
NTP packets exchanged between the UDP transport and the NTP application layers.
Packets are rejected when they are malformed or the MD5 encryption authentication
failed. In addition, time quality can be assessed by looking at the current estimated time
error and comparing it with the time accuracy threshold. Finally, all of the NTP control
information transmitted by the NTS in an NTP packet is available in this enterprise group.
One important variable in this group is ntpSysLeap because it is the clearest indication if
the NTS is telling correct time.
When GPS is used as the time synchronization source, the GPS Enterprise MIB Group
provides detailed information about the satellites used by the NTS. Complete GPS
satellite information exists on the number of satellites tracked and used for timing
purposes, their signal strengths, the tracking mode, altitude, longitude, and latitude of the
GPS antenna. This information allows you to properly set up the GPS antenna and to use
the unit for time information.
When ACTS is used as the time synchronization source (see Appendix E for details), the
ACTS Enterprise MIB Group provides detailed information on the ACTS dial-up modem
time service. Complete information on the number and success of the ACTS phone calls
as well as a detailed break down of the various possible modem and line failures that can
occur. This information allows you to fine tune calling frequency with the desired time
accuracy and assess the telephone line quality of the connection to the ACTS service.
Obtaining the enterprise MIB information requires you to have an SNMP management
program running on your computer.
Variable Definitions
This section contains a complete and formal definition of Symmetricom’s SNMP
enterprise MIB group, including all the variables in Symmetricom's Enterprise MIB, along
with the MIB OID address and data types.
An electronic form of this file was included with this manual. If the disk has been
misplaced or corrupted, a copy can be obtained from Symmetricom’s web site
(www.truetime.net). Select Products and Literature>Reference Material to get there.
The file’s name is “TrueTime.MIB”, and should compile for virtually any SNMP
management software. It has been verified to work for Sun’s Solaris X-SNMP and
Hewlett Packard’s OpenView management software packages.