Contents
1 Introduction
This instruction concerns alarm handling for the Storage Engine, Potential Data Inconsistency between Replicas Found in PLDB alarm.
1.1 Alarm Description
The alarm is issued when potential data inconsistency is found in the Processing Layer Database (PLDB). The alarm is raised as a result of the cudbCheckConsistency command periodical execution. For further information, refer to CUDB Node Commands and Parameters, Reference [1].
The possible alarm causes and the corresponding fault reasons, fault locations, and impacts are described in Table 1.
|
Alarm Cause |
Description |
Fault Reason |
Fault Location |
Impact |
|---|---|---|---|---|
|
Number of rows in some tables is different in the master and slave replicas. |
The lightweight Consistency Check found the number of rows in one or more tables in CUDB to be different in the master and slave replicas by more than the specified margin (in %). |
|
Affected PLDB cluster |
If this slave replica becomes the master replica, there might be a service impact for the subscribers affected by the data inconsistency. |
The alarm attributes are listed and explained in Table 2.
|
Attribute Name |
Attribute Value |
|---|---|
|
Auto Cease |
NO |
|
Application Id |
STORAGE-ENGINE |
|
Error Code |
19 |
|
Timestamp First |
Date and time when the alarm was raised for the first time. |
|
Repeated Counter |
Number which indicates how many times the alarm was raised. |
|
Timestamp Last |
Date and time of the most recent alarm raise. |
|
Model Description |
Potential data inconsistency between replicas found, Storage Engine. |
|
Active Resource Id |
1.3.6.1.4.1.193.169.1.1.19 |
|
Active Description |
Storage Engine (PLDB): Potential data inconsistency between replicas found. |
|
Alarm Event Type |
processingErrorAlarm (4) |
|
Probable Cause |
databaseInconsistency (160) |
|
Severity |
major (4) |
|
Originating source IP |
Node IP where the alarm was raised. |
|
Sequence Number |
Number which indicates the order in which the alarms are raised. |
For further information about attribute descriptions, refer to CUDB Node Fault Management Configuration Guide, Reference [3].
1.2 Prerequisites
This section provides information on the documents, tools, and conditions that apply to the procedure.
1.2.1 Documents
Before starting this procedure, ensure that you have read the following documents:
- CUDB Node Fault Management Configuration Guide, Reference [3], regarding alarm configuration.
- The section on the cudbCheckConsistency command in CUDB Node Commands and Parameters, Reference [1].
- CUDB Subscription Reallocation, Reference [2], regarding the reallocation feature.
- System Safety Information, Reference [5].
- Personal Health and Safety Information, Reference [6].
1.2.2 Tools
Not applicable.
1.2.3 Conditions
Not applicable.
2 Procedure
In case the alarm is raised, do the following:
- Check if the Storage Engine, Replication Channels Down in PLDB alarm is raised for this replica of PLDB. If it is, attend that alarm before attending this one.
- If reallocation, import, or heavy provisioning operations
are ongoing, wait until they finish execution.
Check that replication is working and check the replication delay for this replica of PLDB by executing the following command:
cudbSystemStatus -R
If the replication delay is higher than 10 seconds, check again until replication delay drops below 10 seconds.
- Execute lightweight consistency check again.
- Check the output and if the CUDB_DE or CUDB_DN table, or any table whose name starts with IDEN is mentioned, contact the next level of Ericsson support. Otherwise, proceed to Step 5.
- Clear the alarm manually and order a CUDB
consistency check by executing the following command:
cudbConsistencyMgr --max-replica-lag 10000
Glossary
For the terms, definitions, acronyms and abbreviations used in this document, refer to CUDB Glossary of Terms and Acronyms, Reference [4].
Reference List
| Ericsson Documents |
|---|
| [1] CUDB Node Commands and Parameters. |
| [2] CUDB Subscription Reallocation. |
| [3] CUDB Node Fault Management Configuration Guide. |
| [4] CUDB Glossary of Terms and Acronyms. |
| Other Ericsson Documents |
|---|
| [5] System Safety Information. |
| [6] Personal Health and Safety Information. |