8 Logging
RStudio provides the ability to change various facets of its logging functionality, such as changing the logger type (syslog vs file) on a per-binary or per-section basis. In most configurations, it is recommended that you do not change the logging configuration, but in some circumstances it is desirable to turn on debug logging to help troubleshoot issues.
Configuration File
The logging configuration file is located at /etc/rstudio/logging.conf. It allows you to specify logging options in a hierarchy of three different types:
- Global (
[*]) - Per-binary (
[@binary name]) - Per log section (
[log section name])
For example:
# /etc/rstudio/logging.conf
[*]
log-level=info
logger-type=syslog
[@rserver]
log-level=debug
logger-type=file
max-size-mb=10
[file-locking]
log-dir=/var/log/file-locking
log-file-mode=600This configuration specifies that by default, all logging should be sent to syslog at info level or higher. Debug logging is enabled for the rserver binary specifically, where logs are written to file with a maximum log file size of 10MB, in the default /var/log/rstudio-server directory. File locking logging is also specifically redirected to a different logging directory, /var/log/file-locking, with a specific file creation mode of 600. All logging sections named file-locking which occur in the rserver process will be logged to file, whereas the same logging sections in other binaries will continue to be logged to syslog.
The following settings may be specified in /etc/rstudio/logging.conf:
| Config Option | Description | Default Value |
|---|---|---|
| log-level | The minimum log level to capture. Can be one of debug, info, warn, or error. |
warn |
| logger-type | The type of logger to use. Can be one of stderr, syslog, or file. |
syslog |
When using the file logger, the following can also be specified:
| Config Option | Description | Default Value |
|---|---|---|
| log-dir | The log directory to store log files in. The resulting log file name is based on the binary name (and optionally the process ID). | /var/log/rstudio-server |
| log-file-mode | The filemode to use when creating the log file. Must be a valid POSIX octal file mode. | 666 (All read/write) |
| log-file-include-pid | Whether to include the process id in the filename. Useful for differentiating between multiple processes of the same name. Can be 0 (false) or 1 (true) |
0 (false) |
| rotate | Whether or not to rotate the log file as it reaches maximum size. Can be 0 (false) or 1 (true) |
1 (true) |
| max-size-mb | Maximum allowable size of the file before it is rotated. Only applicable if rotate is enabled. | 2 (MB) |
List of Logging Sections
The following is a list of logging sections that may be used within the logging configuration file.
| Section Name | Description |
|---|---|
| file-locking | Logging of file locking operations, such as processes acquiring and releasing locks. |
Reloading Configuration
In order to reload the logging settings during run-time of a process, simply send the SIGHUP signal to the desired process, and the logging configuration will be reloaded for that binary.
For example, to send the SIGHUP signal to the rserver process after changing the configuration file:
pidof rserver | sudo xargs kill -s SIGHUP