rsyslog

Supported OS Linux

Overview

Configure Rsyslog to gather logs from your host, containers, and services.

Setup

Log collection

Rsyslog version >=8

From version 8.1.5 Rsyslog recommends inotify mode. Traditionally, imfile used polling mode, which is much more resource-intense (and slower) than inotify mode.
  1. Activate the imfile module to monitor specific log files. To add the imfile module, add the following to your rsyslog.conf:

    module(load="imfile" PollingInterval="10") #needs to be done just once
    
  2. Create an /etc/rsyslog.d/datadog.conf file.

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration and replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<APP_NAME_OF_FILE1>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - - %msg%\n"
    
    ruleset(name="infiles") {
    action(type="omfwd" protocol="tcp" target="intake.logs.<site_url>" port="10514" template="DatadogFormat")
    }
    

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration. Replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<TAGS>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    template(name="test_template" type="list") { constant(value="{") property(name="msg" outname="message" format="jsonfr") constant(value="}")}
    
    # include the omhttp module
    module(load="omhttp")
    
    ruleset(name="infiles") {
       action(type="omhttp" server="http-intake.logs.<site_url>" serverport="443" restpath="api/v2/logs" template="test_template" httpheaders=["DD-API-KEY: <API_KEY>", "Content-Type: application/json"])
    }
    

  1. Restart Rsyslog. Your new logs are forwarded directly to your Datadog account.

    sudo systemctl restart rsyslog
    
  2. Associate your logs with the host metrics and tags.

    To make sure that your logs are associated with the metrics and tags from the same host in your Datadog account, set the HOSTNAME in your rsyslog.conf to match the hostname of your Datadog metrics.

    • If you specified a hostname in datadog.conf or datadog.yaml, replace the %HOSTNAME% value in rsyslog.conf to match your hostname.
    • If you did not specify a hostname in datadog.conf or datadog.yaml, you do not need to change anything.
  3. To get the best use out of your logs in Datadog, set a source for the logs.

    • If you forward your logs to the Datadog Agent, you can set the source in the Agent configuration file.

    • If you’re not forwarding your logs to the Datadog Agent, create a distinct configuration file for each source in /etc/rsyslog.d/.

      To set the source, use the following format (if you have several sources, change the name of the format in each file):

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\"] %msg%\n"
      

      You can add custom tags with the ddtags attribute:

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\" ddtags=\"env:dev,<KEY:VALUE>\"] %msg%\n"
      
  4. (Optional) Datadog cuts inactive connections after a period of inactivity. Some versions of Rsyslog are not able to reconnect when necessary. To mitigate this issue, use time markers so the connection never stops:

    1. Add the following lines to your Rsyslog configuration file:

      $ModLoad immark
      $MarkMessagePeriod 20
      
    2. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account.
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo apt-get install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/ssl/certs/ca-certificates.crt
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="intake.logs.datadoghq.com" port="10516" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.com" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account.
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo apt-get install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/ssl/certs/ca-certificates.crt
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="tcp-intake.logs.datadoghq.eu" port="443" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.eu" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. Activate the imfile module to monitor specific log files. To add the imfile module, add the following to your rsyslog.conf:

    module(load="imfile" PollingInterval="10") #needs to be done just once
    
  2. Create an /etc/rsyslog.d/datadog.conf file.

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration and replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<APP_NAME_OF_FILE1>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - - %msg%\n"
    
    ruleset(name="infiles") {
    action(type="omfwd" protocol="tcp" target="intake.logs.<site_url>" port="10514" template="DatadogFormat")
    }
    

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration. Replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<TAGS>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    template(name="test_template" type="list") { constant(value="{") property(name="msg" outname="message" format="jsonfr") constant(value="}")}
    
    # include the omhttp module
    module(load="omhttp")
    
    ruleset(name="infiles") {
       action(type="omhttp" server="http-intake.logs.<site_url>" serverport="443" restpath="api/v2/logs" template="test_template" httpheaders=["DD-API-KEY: <API_KEY>", "Content-Type: application/json"])
    }
    

  1. Restart Rsyslog. Your new logs are forwarded directly to your Datadog account.

    sudo systemctl restart rsyslog
    
  2. Associate your logs with the host metrics and tags:

    To make sure that your logs are associated with the metrics and tags from the same host in your Datadog account, set the HOSTNAME in your rsyslog.conf to match the hostname of your Datadog metrics.

    • If you specified a hostname in datadog.conf or datadog.yaml, replace the %HOSTNAME% value in rsyslog.conf to match your hostname.
    • If you did not specify a hostname in datadog.conf or datadog.yaml, you do not need to change anything.
  3. To get the best use out of your logs in Datadog, set a source for the logs.

    • If you forward your logs to the Datadog Agent, you can set the source in the Agent configuration file.

    • If you’re not forwarding your logs to the Datadog Agent, create a distinct configuration file for each source in /etc/rsyslog.d/:

      To set the source, use the following format (if you have several sources, change the name of the format in each file):

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\"] %msg%\n"
      

      You can add custom tags with the ddtags attribute:

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\" ddtags=\"env:dev,<KEY:VALUE>\"] %msg%\n"
      
  4. (Optional) Datadog cuts inactive connections after a period of inactivity. Some versions of Rsyslog are not able to reconnect when necessary. To mitigate this issue, use time markers so the connection never stops:

    1. Add the following two lines to your Rsyslog configuration file:

      $ModLoad immark
      $MarkMessagePeriod 20
      
    2. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account.
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo yum install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="intake.logs.datadoghq.com" port="10516" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.com" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account:
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo yum install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="tcp-intake.logs.datadoghq.eu" port="443" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.eu" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. Activate the imfile module to monitor specific log files. To add the imfile module, add the following to your rsyslog.conf:

    module(load="imfile" PollingInterval="10") #needs to be done just once
    
  2. Create an /etc/rsyslog.d/datadog.conf file.

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration and replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<APP_NAME_OF_FILE1>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - - %msg%\n"
    
    ruleset(name="infiles") {
    action(type="omfwd" protocol="tcp" target="intake.logs.<site_url>" port="10514" template="DatadogFormat")
    }
    

  1. In /etc/rsyslog.d/datadog.conf, add the following configuration. Replace <site_url> with and <API_KEY> with your Datadog API key. You must include a separate input line for each log file you want to monitor:

    ## For each file to send
    input(type="imfile" ruleset="infiles" Tag="<TAGS>" File="<PATH_TO_FILE1>")
    
    ## Set the Datadog Format to send the logs
    template(name="test_template" type="list") { constant(value="{") property(name="msg" outname="message" format="jsonfr") constant(value="}")}
    
    # include the omhttp module
    module(load="omhttp")
    
    ruleset(name="infiles") {
       action(type="omhttp" server="http-intake.logs.<site_url>" serverport="443" restpath="api/v2/logs" template="test_template" httpheaders=["DD-API-KEY: <API_KEY>", "Content-Type: application/json"])
    }
    

  1. Restart Rsyslog. Your new logs are forwarded directly to your Datadog account.

    sudo systemctl restart rsyslog
    
  2. Associate your logs with the host metrics and tags:

    To make sure that your logs are associated with the metrics and tags from the same host in your Datadog account, set the HOSTNAME in your rsyslog.conf to match the hostname of your Datadog metrics.

    • If you specified a hostname in datadog.conf or datadog.yaml, replace the %HOSTNAME% value in rsyslog.conf to match your hostname.
    • If you did not specify a hostname in datadog.conf or datadog.yaml, you do not need to change anything.
  3. To get the best use out of your logs in Datadog, set a source for the logs.

    • If you forward your logs to the Datadog Agent, you can set the source in the Agent configuration file.

    • If you’re not forwarding your logs to the Datadog Agent, create a distinct configuration file for each source in /etc/rsyslog.d/:

      To set the source, use the following format (if you have several sources, change the name of the format in each file):

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\"] %msg%\n"
      

      You can add custom tags with the ddtags attribute:

      $template DatadogFormat,"<DATADOG_API_KEY> <%pri%>%protocol-version% %timestamp:::date-rfc3339% %HOSTNAME% %app-name% - - [metas ddsource=\"<MY_SOURCE_NAME>\" ddtags=\"env:dev,<KEY:VALUE>\"] %msg%\n"
      
  4. (Optional) Datadog cuts inactive connections after a period of inactivity. Some versions of Rsyslog are not able to reconnect when necessary. To mitigate this issue, use time markers so the connection never stops:

    1. Add the following two lines to your Rsyslog configuration file:

      $ModLoad immark
      $MarkMessagePeriod 20
      
    2. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account.
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo dnf install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="intake.logs.datadoghq.com" port="10516" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.com" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

  1. (Optional) Add TLS Encryption to logs sent from Rsyslog to your Datadog account.
    1. Install the rsyslog-gnutls and ca-certificates packages:

      sudo dnf install rsyslog-gnutls ca-certificates
      
    2. Add the following line to the bottom of your /etc/rsyslog.d/datadog.conf file:

      ## Define the destination for the logs
      $DefaultNetstreamDriverCAFile /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
      ruleset(name="infiles") {
          action(type="omfwd" protocol="tcp" target="tcp-intake.logs.datadoghq.eu" port="443" template="DatadogFormat" StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="x509/name" StreamDriverPermittedPeers="*.logs.datadoghq.eu" )
      }
      
    3. Restart the Rsyslog service:

      sudo systemctl restart rsyslog
      

Troubleshooting

Need help? Contact Datadog support.