## 8.2.1  SAP HANA System Replication Alerts
This is an overview of all alerts issued for the primary system.
| Alert ID 78   | Connection Closed                                                  |
|---------------|--------------------------------------------------------------------|
| Description   | Alert 78 is raised when a system replication connection is closed. |
| Alert ID 79   | Configuration Parameter Mismatch                                                                                  |
|---------------|-------------------------------------------------------------------------------------------------------------------|
| Description   | Alert 79 is raised when there is a configuration parameter mismatch between the primary and the secondary system. |
## Alert ID 94
## Description
## Logreplay Backlog
Alert 94 is raised when the system replication logreplay backlog increases. A delayed log replay on the secondary system causes a longer takeover time.
The alert has a different priority based on the size of the redo log that was not yet replayed:
- Low: 10 GB &lt; logreplay backlog &lt; 50 GB
- Medium: 50 GB &lt;= logreplay backlog &lt; 500 GB
- High: logreplay backlog &gt;= 500 GB
To identify the reason for the increased system replication logreplay backlog, check the state of the services on the secondary system. To get more information, monitor the secondary system. Possible causes for the increased system replication logreplay backlog can be, for example, a slow or not functioning log replay, or a non-running service on the secondary system.
## Alert ID 104 Increased Log Shipping Backlog
## Description
Alert 104 is raised when the system replication log shipping is delayed or does not work properly causing data loss on the secondary system, if a takeover is done.
The alert has a different priority based on the threshold reached:
- Low: 1 GB &lt; log shipping backlog &lt; 10 GB
- Medium: 10 GB &lt;= log shipping backlog &lt; 50 GB
- High: log shipping backlog &gt;= 50 GB
To identify the reason for the increased system replication log shipping backlog, check the sta­ tus of the secondary system. Possible causes for the increased system replication log shipping backlog can be a slow network performance, connection problems, or other internal issues (for example, in SYNC or SYNCMEM replication modes).
## Alert ID 106 ASYNC Replication In-Memory Buffer Overflow
## Description
Alert 106 is raised when the local in-memory buffer in the ASYNC replication mode is running full indicating possible network issues with the connection to the secondary system.
The alert has a different priority based on the threshold reached:
- Medium: if buffer runs full once within 24 hours
- High: if buffer runs full more than once within 24 hours To identify the reason for the local in-memory buffer running full, check the buffer size, the
network, the IO on the secondary system, or look for peak loads.
The alert depends on the setting of the logshipping\_async\_wait\_on\_buffer\_full parameter. For more information about this parameter, see SAP HANA System Replication Configuration Parameters .
| Alert ID 107   | Inconsistent fallback snapshot                                                                                                                                                          |
|----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Description    | Alert 107 is raised for the primary and the secondary systems when there are broken fallback snapshots. For more information about fallback snapshots, see Create a Fallback Snapshot . |
##  Note
Before SAP HANA 1.0 SPS 09 there was one alert categorized as "Internal Event" (Alert 21) which covered alerts 78 and 79. Both situations were covered by one event type and could only be distinguished by the information text provided. Since SAP HANA 1.0 SPS 11 old style alerts based on alert 21 are not created anymore as a default.
You can create them by setting the configuration parameter keep\_old\_style alert to true . These alerts can be required to keep the existing monitoring infrastructure working. If activated, new alerts and old style alerts are created in parallel. Old alerting can be disabled by setting the keep\_old\_style alert configuration parameter to false in global.ini file.
The new alerts require that you have migrated to the embedded statistics server. For more information, see SAP Note 1917938 .
## Related Information
Monitoring Secondary Systems [page 155]
SAP HANA System Replication Configuration Parameters [page 62] Create a Fallback Snapshot SAP Note 1917938