Squirro offers a number of ways to debug what is happening in the system. Each service maintains its log file, which helps with finding the source of an error. Additionally pre-installed daemon Monit helps by automatically restarting services that fail completely. A few basic operating system commands are also explained here, which can be used to find out if the base system is running smoothly.
Table of Contents
Log files
All log files can be found in the /var/log directory. The following table shows the relevant log files and their usage.
| Log File | Service | Additional Notes |
|---|---|---|
/var/log/squirro/squirro-*.log | Squirro services | Detailed log file about each service. Symlink to /var/log/squirro/SERVICE_NAME/SERVICE_NAME.log. |
/var/log/squirro/nginx-*-access.log | Nginx (Squirro services) | Every request to the web services is recorded in this log file in a line-by-line format. Symlink to /var/log/squirro/SERVICE_NAME/nginx-access.log. |
/var/log/squirro/nginx-*-error.log | Nginx (Squirro services) | Records errors on the HTTP level. When a service is stopped, errors may show up here indicating that the service is not reachable. Symlink to /var/log/squirro/SERVICE_NAME/nginx-error.log. |
/var/log/messages | - | General system log. Serious system failures will be recorded here. |
/var/log/elasticsearch/squirro.log | Elasticsearch | Records cluster information and major failures. |
/var/log/redis/redis.log | Redis | |
/var/log/mysqld.log | MySQL | |
/var/log/cron | Cron | |
/var/log/monit/monit.log | Monit | Records service state changes and actions. |
Monit
System commands
Processor usage
Disk usage
Following log files