postgresql module collects and parses logs created by
When you run the module, it performs a few tasks under the hood:
- Sets the default paths to the log files (but don’t worry, you can override the defaults)
- Makes sure each multiline log event gets sent as a single event
- Uses ingest node to parse and process the log lines, shaping the data into a structure suitable for visualizing in Kibana
- Deploys dashboards for visualizing the log data
Read the quick start to learn how to configure and run modules.
This module comes in two flavours: a parser of log files based on Linux distribution defaults, and a CSV log parser, that you need to enable in database configuration.
postgresql module using
.log was tested with logs from versions 9.5 on Ubuntu,
9.6 on Debian, and finally 10.11, 11.4 and 12.2 on Arch Linux 9.3.
postgresql module using
.csv was tested using versions 11 and 13 (distro is not relevant here).
Supported log formatsedit
This module can collect any logs from PostgreSQL servers, but to be able to better analyze their contents and extract more information, they should be formatted in a determined way.
There are some settings to take into account for the log format.
Log lines should be preffixed with the timestamp in milliseconds, the process id, the user id and the database name. This uses to be the default in most distributions, and is translated to this setting in the configuration file:
log_line_prefix = '%m [%p] %q%u@%d '
PostgreSQL server can be configured to log statements and their durations and this module is able to collect this information. To be able to correlate each duration with their statements, they must be logged in the same line. This happens when the following options are used:
log_duration = 'on' log_statement = 'none' log_min_duration_statement = 0
Setting a zero value in
log_min_duration_statement will log all statements
executed by a client. You probably want to configure it to a higher value, so it
logs only slower statements. This value is configured in milliseconds.
log_duration together, statements and durations
are logged in different lines, and Filebeat is not able to correlate both
values, for this reason it is recommended to disable
The PostgreSQL module of Metricbeat is also able to collect information about all statements executed in the server. You may chose which one is better for your needings. An important difference is that the Metricbeat module collects aggregated information when the statement is executed several times, but cannot know when each statement was executed. This information can be obtained from logs.
Other logging options that you may consider to enable are the following ones:
log_checkpoints = 'on'; log_connections = 'on'; log_disconnections = 'on'; log_lock_waits = 'on';
log_disconnections can cause a lot of events if you
don’t have persistent connections, so enable with care.
Using CSV logsedit
Since the PostgreSQL CSV log file is a well-defined format, there is almost no configuration to be done in Filebeat, just the filepath.
On the other hand, it’s necessary to configure postgresql to emit
The recommended parameters are:
logging_collector = 'on'; log_destination = 'csvlog';
Configure the moduleedit
You can further refine the behavior of the
postgresql module by specifying
variable settings in the
modules.d/postgresql.yml file, or overriding settings at the command line.
The following example shows how to set paths in the
file to override the default paths for PostgreSQL logs:
- module: postgresql log: enabled: true var.paths: ["/path/to/log/postgres/*.log*"]
To specify the same settings at the command line, you use:
Each fileset has separate variable settings for configuring the behavior of the
module. If you don’t specify variable settings, the
postgresql module uses
For advanced use cases, you can also override input settings. See Override input settings.
When you specify a setting at the command line, remember to prefix the
setting with the module name, for example,
log fileset settingsedit
An array of glob-based paths that specify where to look for the log files. All
patterns supported by Go Glob
are also supported here. For example, you can use wildcards to fetch all files
from a predefined level of subdirectories:
/path/to/log/*/*.log. This fetches all
.logfiles from the subfolders of
/path/to/log. It does not fetch log files from the
/path/to/logfolder itself. If this setting is left empty, Filebeat will choose log paths based on your operating system.
This module comes with two sample dashboards.
The first dashboard is for regular logs.
The second one shows the slowlogs of PostgreSQL. If
is not used, this dashboard will show incomplete or no data.
For a description of each field in the module, see the exported fields section.