The Farmguardian section provides a list of all available health checks in the load balancer, including descriptions and their application to various farms.

Farmguardian offers advanced backend monitoring, automatically disabling any server that fails a health check and marking its IP as blacklisted.

Health checks can be either pre-configured or custom. You can identify the type by looking at the action column: pre-configured checks have grayed-out settings, while custom checks can be edited by clicking the pencil icon.

Actions Menu #

Create Farmguardian. Opens the form to create a new Farmguardian check.
Delete. Removes the selected Farmguardian check.

Farmguardian Table Descriptions #

Name. Descriptive name of the Farmguardian check.
Description. Brief explanation of the health check.
Command. Commands and parameters executed at intervals against each backend of the farm.
Farms. Lists the farms and services using the specific check.
Actions. Manage the Farmguardian checks with the following options:

• Edit. Opens the configuration screen for custom Farmguardian checks.
• Delete. Removes a selected Farmguardian check, with a notification if it’s assigned to any service.

Pre-configured health checks #

check_redis: Checks the master role for a Redis server; marks the backend as DOWN if the master role is absent.
check_tcp: Sends a TCP connection to the backend.
check_udp: Sends a UDP connection to the backend and checks if the port is open.
check_http: Sends an HTTP request expecting a 200 OK response within 5 seconds.
check_https: Sends an HTTPS request expecting a 200 OK response within 5 seconds.
check_smtp: Sends an SMTP connection expecting an SMTP OK response within 5 seconds.
check_https_response_string: Sends an HTTPS request expecting a 200 OK response and a specific string in the HTML within 5 seconds.
check_http_response_string: Sends an HTTP request expecting a 200 OK response and a specific string in the HTML within 5 seconds.
check_pop: Sends a POP connection expecting a POP OK response within 5 seconds.
check_ldap: Sends an LDAP query expecting an LDAP bind within 5 seconds, with customizable base search, user to bind, and user password. Change -b (base search), -D (user to bind), -P (user password).
check_ldaps: Sends an LDAPS query expecting an LDAP bind within 5 seconds, with customizable base search, user to bind, and user password. Change -b (base search), -D (user to bind), -P (user password).
check_imap: Sends an IMAP connection expecting an IMAP OK response within 5 seconds.
check_top: Sends a TCP connection to the backend.
check_sip: Tests a SIP server/device for availability and response time.
check_ping: Sends 2 ICMP packets, ensuring 100% packet reach to the host.
check_common: Checks the /usr/lib/nagios/plugins folder for more checks; use –help for additional info.

For creating custom Farmguardian checks, refer to the Create a custom Farmguardian check guide.