OpenLDAP Prometheus Exporter

This is a simple service that scrapes metrics from OpenLDAP and exports them via HTTP for Prometheus consumption.

This exporter is based on the ideas in https://github.com/jcollie/openldap_exporter, but it is written in golang to allow for simpler distribution and installation.

Setting up OpenLDAP for monitoring

slapd supports an optional LDAP monitoring interface you can use to obtain information regarding the current state of your slapd instance. Documentation for this backend can be found in the OpenLDAP backend guide and administration guide.

To enable the backend add the following to the bottom of your slapd.conf file:

database monitor
rootdn "cn=monitoring,cn=Monitor"
rootpw YOUR_MONITORING_ROOT_PASSWORD

Technically you don't need rootdn or rootpw, but having unauthenticated access to slapd feels a little wrong.

You may need to also load the monitoring backend module if your slapd installation needs to load backends as modules by adding this to your slapd.conf:

moduleload  back_monitor

Once you've built the exporter (see below), or downloaded the latest release, you can install it on the same server as your slapd instance, and run it as a service. You can then configure Prometheus to pull metrics from the exporter's /metrics endpoint on port 9330, and check to see that it is working via curl:

$> curl -s http://localhost:9330/metrics
...
# HELP openldap_monitor_counter_object cn=Monitor (objectClass=monitorCounterObject) monitorCounter
# TYPE openldap_monitor_counter_object gauge
openldap_monitor_counter_object{dn="cn=Bytes,cn=Statistics,cn=Monitor"} 1.857812777e+09
openldap_monitor_counter_object{dn="cn=Current,cn=Connections,cn=Monitor"} 50
openldap_monitor_counter_object{dn="cn=Entries,cn=Statistics,cn=Monitor"} 4.226632e+06
openldap_monitor_counter_object{dn="cn=Max File Descriptors,cn=Connections,cn=Monitor"} 1024
openldap_monitor_counter_object{dn="cn=PDU,cn=Statistics,cn=Monitor"} 4.446117e+06
openldap_monitor_counter_object{dn="cn=Read,cn=Waiters,cn=Monitor"} 31
openldap_monitor_counter_object{dn="cn=Referrals,cn=Statistics,cn=Monitor"} 0
openldap_monitor_counter_object{dn="cn=Total,cn=Connections,cn=Monitor"} 65383
openldap_monitor_counter_object{dn="cn=Write,cn=Waiters,cn=Monitor"} 0
# HELP openldap_monitor_operation cn=Operations,cn=Monitor (objectClass=monitorOperation) monitorOpCompleted
# TYPE openldap_monitor_operation gauge
openldap_monitor_operation{dn="cn=Abandon,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Add,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Bind,cn=Operations,cn=Monitor"} 57698
openldap_monitor_operation{dn="cn=Compare,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Delete,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Extended,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Modify,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Modrdn,cn=Operations,cn=Monitor"} 0
openldap_monitor_operation{dn="cn=Search,cn=Operations,cn=Monitor"} 161789
openldap_monitor_operation{dn="cn=Unbind,cn=Operations,cn=Monitor"} 9336
# HELP openldap_monitored_object cn=Monitor (objectClass=monitoredObject) monitoredInfo
# TYPE openldap_monitored_object gauge
openldap_monitored_object{dn="cn=Active,cn=Threads,cn=Monitor"} 1
openldap_monitored_object{dn="cn=Backload,cn=Threads,cn=Monitor"} 1
openldap_monitored_object{dn="cn=Max Pending,cn=Threads,cn=Monitor"} 0
openldap_monitored_object{dn="cn=Max,cn=Threads,cn=Monitor"} 16
openldap_monitored_object{dn="cn=Open,cn=Threads,cn=Monitor"} 8
openldap_monitored_object{dn="cn=Pending,cn=Threads,cn=Monitor"} 0
openldap_monitored_object{dn="cn=Starting,cn=Threads,cn=Monitor"} 0
openldap_monitored_object{dn="cn=Uptime,cn=Time,cn=Monitor"} 1.225737e+06
# HELP openldap_scrape successful vs unsuccessful ldap scrape attempts
# TYPE openldap_scrape counter
openldap_scrape{result="ok"} 6985
...

Command line configuration

The binary itself is configured via command line flags:

Usage of ./target/openldap_exporter:
  -interval duration
        Scrape interval (default 30s)
  -ldapAddr string
        Address of OpenLDAP server (default "localhost:389")
  -ldapPass string
        OpenLDAP bind password (optional)
  -ldapUser string
        OpenLDAP bind username (optional)
  -promAddr string
        Bind address for prometheus HTTP metrics server (default ":9330")
  -version
        Show version and exit

Configuration through environment variables

The binary can also be configured via environment variables. The same parameters can be set as with the command line flags. If both command line flags and environment variables are defined, command line flags take precedence.

Mapping of command line flags to environment variables is shown in the table below:

Cmd Flag	Env Var
interval	INTERVAL
ldapAddr	LDAP_ADDR
ldapPass	LDAP_PASS
ldapUser	LDAP_USER
promAddr	PROM_ADDR

Example:

LDAP_PASS=secret ./openldap_exporter --ldapUser test

Build

1. Install Go 1.13 from https://golang.org/
2. Build the binaries: make build