When viewing historical trace data, you will not see data for as long as the configured amount of days in IntroscopeEnterpriseManager.properties, according to this property:
This would affect all types of event - traces, errors
Data would be missing in both the Traces and/or Errors tab and in the Historical Query Viewer.
In a cluster environment, the situation would be the same if logging the Workstation / WebView into the MOM or directly to the collector.
There are no obvious error messages - trace data would be retrieved for the last 24 or 48 hours but definitely not for the last 14 days.
If the above property is configured to a value of 14, you will not see 14 individual traces_YYYYMMDD.db files in the /traces folder of each Enteprise Manager
All APM releases since APM 9.1 where clamps are configured in apm-events-thresholds-config.xml, any OS, standalone or cluster.
The apm-events-thresholds-config.xml in the /config folder of each Enterprise Manager has a clamp on the amount of disk space used by trace events.
This is the relevant property
By default it is configured to a value of 1024, the value is in MB so this equates to 1GB
Where the individual trace_YYYYMMDD.db files combined file size is greater than 1GB, files will be removed - oldest first, until we reach the storage limit, so the data will not be available to be queried from Workstation/WebView.
1. Access the file system of each collector in the cluster and go to the /traces folder.
2. Check each traces_YYYYMMDD and find the file with largest filesize.
3. Based on configuration of:
Calculate the required disk usage, and therefore an estimated value for the clamp property.
So, if the largest file is 700 MB, we would do:
700 x 14 = 9800 MB (9.8 GB)
4. Go to apm-events-thresholds.config.xml on each Enterprise Manager and update the value of
introscope.enterprisemanager.transactionevents.storage.max.disk.usage to the calculated value, in this case 9800
See: traces.db Disk Space Calculation Example for details of how much disk space traces could use and how high the clamp could need to be configured at to avoid data loss.