7.1 Introduction
The MultiMux is designed to make it easy to operate and maintain. The procedures in this chapter will help isolate any problem you have to a specific component of your network, at which point you will be instructed to call the appropriate personnel or execute commands to adjust operating conditions.
There are no specific repair procedures besides command execution and switch settings that you are expected to perform in MultiMux maintenance.
An important part of the MultiMux design is its remote diagnostic capabilities. Our Tech Support department personnel can
7.2
ImportanceofCompositeStatistics
The Composite Statistics Command AT#SA/B provides additional information concerning the operation of your composite link that can aid you in testing for problems. The composite report generated by this command can be very valuable when used in conjunction with Analog Loopback testing. For example, if your REMOTE DWN indicator is on, you could run an Analog Loopback test to make sure the failure is not in the MultiMux. If the test runs correctly, you then can check the composite statistics for additional information.
The data in the composite statatistics report will tell you more about line failure conditions. The following items are on your composite status report:
| COMPOSITE STATISTICS |
|
| ||
ELAPSED TIME | : | 00 DAYS | 00HRS | 00 | MIN. |
DATA BLOCKS TRANSMITTED | : |
|
| 0 |
|
DATA BLOCKS RETRANSMITS | : |
|
| 0 |
|
DATA BLOCKS RECEIVED | : |
|
| 0 |
|
RECEIVE BLOCK ERRORS | : |
|
| 0 |
|
VOICE/FAX BLOCKS TRANSMITTED | : |
|
| 0 |
|
VOICE/FAX BLOCKS RECEIVED | : |
|
| 0 |
|
LINK ALARMS | : |
|
| 0 |
|
REMOTE DOWNS | : |
|
| 0 |
|
LINK UTILIZATION | : |
|
| 0% | |
RECEIVE FLOW CONTROL TIME | : | 00 HRS | 00 MIN | 00 SEC. | |
AUTOMATIC REPORTING | : | OFF 9600 | BAUD |
|
|
Comparing the number of blocks transmitted with the number of retransmits needed to get the data through can indicate a line problem. Comparing the blocks received and receive block errors indicates the same problem from the other end of the link. The comparative numbers that you might encounter could be 10,000 blocks transmitted (or received) with 500 or 1000 retransmits (or receive block errors).
Link Alarms simply tell you that there are some sort of problems on the link. You will find that the Link Alarm numbers will correspond to the Retransmit and Receive Block numbers. Specifically, a Link Alarm means that it has been 10 seconds since the MultiMux has received an acknowledgment. Normally, three acknowledgments will be received during a 10 second period.
The Remote Down entry means that a MultiMux has sent data 30 times and could not get it through (the link has been broken).
The other entries in the composite status report do not apply to link problems.