Cache Server Logs

Cache server logs are server-side log files generated for each running cache. They record cache runtime activity, cache lifecycle events, cluster membership changes, state transfer activity, replication behavior, warnings, errors, and critical cache conditions. These logs are usually the first place to check when diagnosing cache startup issues, node join/leave problems, state transfer delays, replication issues, or cache runtime errors. If multiple caches are running on the same server, each cache can generate its own log output. In a clustered cache, each server node writes its own cache log, so you should review logs from all affected nodes when diagnosing cluster-wide issues.

When Cache Server Logs Help

Cache server logs are useful when an issue is related to the runtime behavior of a cache or its cluster. For example, if a cache does not start, a node fails to join the cluster, state transfer takes longer than expected, or a cache reports runtime errors, the cache log usually provides the first diagnostic trail.

In clustered topologies, each server node writes its own cache log. Troubleshooting should therefore use logs from all affected nodes for the same time window, especially for membership changes, state transfer, or replication.

Diagnostic Area What To Look For
Cache lifecycle Cache start, stop, initialization, and startup failures.
Cluster membership Node join, node leave, cluster view changes, and communication issues.
State transfer State transfer start, progress, completion, interruption, or failure.
Runtime health Errors, critical conditions, and resource-related messages.
Detailed diagnostics Operation-level traces when detailed/debug logging is enabled.

Cache Log Location and File Naming

By default, NCache writes cache logs to the following locations:

  • Windows: Available at %NCHOME%\log-files.
  • Linux: Available at /opt/ncache/log-files.

Cache log file names usually include the cache name, timestamp, and server IP address. This helps identify which cache and server node generated the log.

If a custom log path is configured for a cache, cache logs are written to that path instead of the default log directory.

Note

A custom log path can be specified for a cache through the log-path attribute in config.ncconf, or from the NCache Management Center under the cache's Advanced Settings.

For clustered caches, each server node generates its own cache log. When troubleshooting a cluster issue, collect logs from all affected server nodes for the same time range.

Cache Server Logging Levels

NCache cache server logs support multiple logging levels. Use the level that provides enough diagnostic detail for the issue being investigated, while keeping production overhead in mind.

Logging Level Description Typical Use
INFO Records operational information about cache activity, such as state transfer start and stop events. This level is disabled by default. Use when you need more visibility into normal cache and cluster activity.
ERROR Records errors raised during cache operations. Use for common troubleshooting scenarios such as cache startup failures, cluster join issues, or runtime operation errors.
CRITICAL Records serious cache conditions that require immediate attention, such as the cache exceeding its memory limit. Use to identify high-priority cache health or resource issues.
Detail DEBUG Records detailed operation-level information, including cache operation details and state transfer activity. This level is disabled by default and can affect cache performance. Use only for deep diagnostics when normal logs are not enough.
Important

Enable detailed or debug-level logging only when needed for diagnostics, and disable it before returning the cache to normal production load.

Note

If Cache Health Alerts are enabled, NCache can also write resource-threshold alerts to the cache log. These alerts can help identify cache health conditions such as high memory usage, CPU usage, network usage, request rate, queue size, or connected-client count. Cache Health Alerts are configured separately from cache server logging.

Configure Cache Server Logging

Error logging is enabled by default, while detailed logging can be enabled when deeper diagnostics are required. You can configure detailed cache logging from the NCache Management Center or by editing the cache configuration manually.

Using NCache Management Center

To configure detailed cache logging from the NCache Management Center:

  • Open the NCache Management Center.
  • Go to Clustered Caches or Local Caches.
  • Select the cache for which you want to configure logging.
  • Stop the cache before changing logging settings.
  • Click View Details, and go to Advanced Settings > Options.
  • Select Enable detailed error logging if detailed logs are required.
  • Specify the Log File Path if you want to save these logs to a different path.
  • Save the changes.
  • Start the cache again.

Using config.ncconf

By default, error tracing is enabled, while notice, warning, and debug tracing are disabled. Detailed logging should be enabled only when deeper diagnostics are required. You can configure cache logging manually in config.ncconf under the <cache-settings> section.

<cache-settings ...>
  <logging enable-logs="True"
           trace-errors="True"
           trace-notices="False"
           trace-warnings="False"
           trace-debug="False"
           log-path=""/>
</cache-settings>
Attribute Description
enable-logs Enables or disables cache logging.
trace-errors Logs error traces, essential for identifying and troubleshooting critical issues.
trace-notices Logs notice traces for general informational messages.
trace-warnings Logs warning traces, useful for detecting and addressing potential issues.
trace-debug Logs detailed debug traces for deeper diagnostics.
log-path Specifies a custom path where cache logs are written.
Note

If you manually update config.ncconf, apply the change consistently where required and restart the NCache Service for the changes to take effect.

See Also

NCache Log Viewer
Performance Counters Logging
Cache Health Alerts