Symptom:
When the protection path of the ASON diamond SNCP service is interrupted on huawei transmission equipment OSN 9500, the service is interrupted.
Identification method:
1. When the protection path of the ASON SNCP service is interrupted, the service is interrupted.
2. The ASON SNCP service is upgraded from a static SNCP service.
[Root Cause]
This issue occurs when the parameters in the static SNCP service upgrading command issued by the ASON software are specified as follows:
1. The first path (working slot of the ASON SNCP service) is specified as the protection slot of the original static SNCP service.
2. The second path (protection slot of the ASON SNCP service) is specified as the working slot of the original static SNCP service.
In this case, the command parameters can pass the verification performed by the NE software. Then the NE software upgrades the static SNCP service to an ASON SNCP service based on the command. The working and protection slot configuration and SNCP protocol status are updated, but the cross-connect algorithm remains the same. Therefore, the cross-connect algorithm and the SNCP protocol status do not match. As a result, the SNCP switching fails and the ASON SNCP service is interrupted.
[Impact and Risk]
After a static SNCP service is upgraded to an ASON diamond SNCP service, the service is interrupted when the protection path is interrupted.
[Measures and Solutions]
Recovery measures:
Choose either of the following measures:
1. Deactivate and then activate the faulty ASON diamond SNCP service.
2. Perform ASON service route optimization for the faulty ASON diamond SNCP service. Note that the first or second path on the source and sink nodes must be changed so that the ASON SNCP service is deleted and then re-created.
Workarounds:
The workarounds can be performed after a static SNCP service is upgraded to an ASON diamond SNCP service.
Method 1:
After a service has just been upgraded, you can perform ASON service route optimization directly for it (the same as the second measure in “Recovery measure”).
Method 2:
Preparations:
1. Check for BD_STATUS, COMMUN_FAIL, and HDLC_FAIL alarms. Clear them if any. Otherwise, the delivery of all service data will be affected.
Procedure:
1. If none of the preceding alarms exists, run the following commands on the Navigator:
:cfg-set-test:open
:cfg-set-calcmode:full
2. On the NMS or Navigator, configure a higher order service on the NE and then delete it.
3. Run the following commands on the Navigator:
:cfg-set-calcmode:increment
:cfg-set-test:close
Risk:
This solution requires the delivery of all service data. Lower order services may be interrupted for less than 50 ms. It is recommended that you perform the preceding operations during the maintenance window period. For an ASON network, lock ASON services before performing the preceding operations, and unlock the ASON services after completing the operations.
Preventive measures:
Upgrade the software to V100R006C05SPH202 or a later version.
If the issue occurs on an NE of V100R006C03SPC200, perform the preceding workarounds and then install V100R006C03SPH205.
[Support for the Health Check Tool]
The related check case will be added to the health check tool that will be released in November 2013. Fore more Huawei Transmission Network, please get through at www.thunder-link.com, a professional Huawei Transmission distributor.
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