how do i correlate rx crc errors with remote modems - copy

7/23/2019 How Do I Correlate Rx CRC Errors With Remote Modems - Copy

1/5

Rx CRC Error Correlation

[ 1 ]

Rx CRC Error Correlation

Transmit problems on one or more remotes may cause CRC errors on the hub line card that is receivingthe upstream carrier. CRC errors could be caused by any of a number of problems: a remote transmitting

above the saturation point, a bad cable, interference, etc.

If the upstream carrier is being received by an iNFINITI line card, you can use the iDirect Rx CRC Correla-

tion feature to identify which remote or remotes are causing the receive packet errors (Rx CRC errors) on

the card.

This FAQ provides instructions for correlating Rx CRC errors with remote modems in an iDirect Network. It

contains the following sections:

Determining the Inroute IDs for Your Network

Enabling Rx CRC Correlation for Your Inroutes

Connecting to the Protocol Processor Blade Running the CRC Correlation Report

Note: CRC error checking is a processor -intensive operation. To avoid overloading the processes

of your line cards, iDirect recommends that you delete the custom keys that enable Rx CRC

Correlation when you are finished.

Determining the Inroute IDs for Your Network

Follow these steps to determine the Inroute IDs for each Inroute being received by a line card with CRCerrors:

1. In iBuilder, right-click on the Network and select Compare Configurationsfrom the menu.

2. In the Configuration Comparison dialog box, clear the Show Differences Onlycheck box.


2/5


[ 2 ]

3. Examine the Latestpane to determine the Inroute IDs for the Inroutes in your Network. Inroute IDs

are displayed in the format INROUTE_#, where #represents the ID of the Inroute. Note the ID of

each Inroute.


Once you have determined the Inroute IDs, follow these steps to enable Rx CRC correlation for the

Inroutes:

1. In iBuilder, right-click on the Network in the iBuilder tree and select Modify->Item from the menu.

2. Click the Custom tab.


3/5


[ 3 ]

3. Enter a network-level custom key in the following format:

[ I NROUTE_#]di sabl e_l ock = 0

where #is the Inroute ID determined in the previous step.

If you have multiple Inroutes in the Network, you need to create a custom key for each. For exam-ple:

[ I NROUTE_1]di sabl e_l ock = 0

[ I NROUTE_2]di sabl e_l ock = 0etc.

4. Click OKto save your changes.

5. Right-click the Network in the iBuilder tree and selectApply Conf iguration->Networkfrom themenu.

Repeat this process for any other Networks you want to check.


4/5

Connecting to the Protocol Processor Blade

[ 4 ]

Connecting to the Protocol Processor Blade

Once you have configured the custom keys, follow these steps to connect to your protocol processorblades to determine which remotes are causing the errors. Follow these steps to connect to a blade:

1. Using a terminal emulator (such as PuTTY), log on to your NMS server using SSH.

2. From the command line of the NMS server, enter the following command to log onto a blade:

telnet 13255

where IP_Address is the address of the protocol processor blade.

3. Log on to the blade with Username: admin.

Running the CRC Correlation Report

Once you have logged on to a protocol processor blade, follow these steps to view the Rx CRC errors for

the Networks configured to use the blade.

1. From the command line, enter the command sarmtto access the sarmt functions on the blade:

> sarmt;

2. Enter the net listcommand to determine the networks available on this blade. You will see a list of

valid networks, as in the following example:

> net list

Val i d Net works are: 1 4 6

3. Enter the net command to select the Network you want to examine. For example,

> net 1

NETWORK 1

4. Enter the crc reportcommand to see the number of CRC errors generated by each remote over

time. The crc reportcommand has several forms shown in the syntax below:

> crc report

Usage:crc r epor t {dat a| acq| al l } [ r eset ]

5. Enter the following command to see a count of data CRC errors per remote:

> crc report all

3100. 3235 : DATA CRC [ 1]3100. 3502 : DATA CRC [ 5818]3100. 4382 : DATA CRC [ 20]3100. 4463 : DATA CRC [ 3]3100. 4656 : DATA CRC [ 11]3100. 7249 : DATA CRC [ 1369]3100. 8963 : DATA CRC [ 1]3100. 9162 : DATA CRC [ 1]


5/5

Running the CRC Correlation Report

[ 5 ]

You can clear the counts by entering:

> crc report all reset

6. Repeat steps 3through 5for each Network on current blade, or enter the following command to

see all CRC errors for all Networks on the blade:

> net * crc report all

If you have more protocol processor blades to check, execute this procedure again, beginning with the

instructions in the section Connecting to the Protocol Processor Blade on page 4. When you have fin-

ished, iDirect recommends that you delete the custom keys you configured for your Network(s) and re-

apply the changes.

how do i correlate rx crc errors with remote modems - copy

Documents