7. Running slapd

slapd(8) is designed to be run as a standalone service. This allows the server to take advantage of caching, manage concurrency issues with underlying databases, and conserve system resources. Running from inetd(8) is NOT an option.

7.1. Command-Line Options

slapd(8) supports a number of command-line options as detailed in the manual page. This section details a few commonly used options.

        -f <filename>

This option specifies an alternate configuration file for slapd. The default is normally /usr/local/etc/openldap/slapd.conf.

        -F <slapd-config-directory>

Specifies the slapd configuration directory. The default is /usr/local/etc/openldap/slapd.d.

If both -f and -F are specified, the config file will be read and converted to config directory format and written to the specified directory. If neither option is specified, slapd will attempt to read the default config directory before trying to use the default config file. If a valid config directory exists then the default config file is ignored. All of the slap tools that use the config options observe this same behavior.

        -h <URLs>

This option specifies alternative listener configurations. The default is ldap:/// which implies LDAP over TCP on all interfaces on the default LDAP port 389. You can specify specific host-port pairs or other protocol schemes (such as ldaps:// or ldapi://). slapd supports the HAProxy proxy protocol version 2, which allows a load balancer or proxy server to provide the remote client IP address to slapd to be used for access control or logging. Listeners configured using either pldap:/// or pldaps:/// URLS will only accept connections that include the necessary proxy protocol header. Connections to the ports used by these listeners should be restricted at the network level to only trusted load balancers or proxies to avoid spoofing of client IP addresses by third parties.

URL Protocol Transport
ldap:/// LDAP TCP port 389
pldap:/// proxied LDAP TCP port 389
ldaps:/// LDAP over SSL TCP port 636
pldaps:/// proxied LDAP over SSL TCP port 636
ldapi:/// LDAP IPC (Unix-domain socket)

For example, -h "ldaps:// ldap://" will create two listeners: one for the (non-standard) ldaps:// scheme on all interfaces on the default ldaps:// port 636, and one for the standard ldap:// scheme on the localhost (loopback) interface on port 666. Hosts may be specified using using hostnames or IPv4 or IPv6 addresses. Port values must be numeric.

For LDAP over IPC, the pathname of the Unix-domain socket can be encoded in the URL. Note that directory separators must be URL-encoded, like any other characters that are special to URLs. Thus the socket /usr/local/var/ldapi must be encoded as


ldapi: is described in detail in Using LDAP Over IPC Mechanisms [Chu-LDAPI]

Note that the ldapi:/// transport is not widely implemented: non-OpenLDAP clients may not be able to use it.

        -n <service-name>

This option specifies the service name used for logging and other purposes. The default service name is slapd.

        -l <syslog-local-user>

This option specifies the local user for the syslog(8) facility. Values can be LOCAL0, LOCAL1, LOCAL2, ..., and LOCAL7. The default is LOCAL4. This option may not be supported on all systems.

        -u user -g group

These options specify the user and group, respectively, to run as. user can be either a user name or uid. group can be either a group name or gid.

        -r directory

This option specifies a run-time directory. slapd will chroot(2) to this directory after opening listeners but before reading any configuration files or initializing any backends.

        -d <level> | ?

This option sets the slapd debug level to <level>. When level is a `?' character, the various debugging levels are printed and slapd exits, regardless of any other options you give it. Current debugging levels are

Table 7.1: Debugging Levels
Level Keyword Description
-1 any enable all debugging
0   no debugging
1 (0x1 trace) trace function calls
2 (0x2 packets) debug packet handling
4 (0x4 args) heavy trace debugging
8 (0x8 conns) connection management
16 (0x10 BER) print out packets sent and received
32 (0x20 filter) search filter processing
64 (0x40 config) configuration processing
128 (0x80 ACL) access control list processing
256 (0x100 stats) stats log connections/operations/results
512 (0x200 stats2) stats log entries sent
1024 (0x400 shell) print communication with shell backends
2048 (0x800 parse) print entry parsing debugging
16384 (0x4000 sync) syncrepl consumer processing
32768 (0x8000 none) only messages that get logged whatever log level is set

You may enable multiple levels by specifying the debug option once for each desired level. Or, since debugging levels are additive, you can do the math yourself. That is, if you want to trace function calls and watch the config file being processed, you could set level to the sum of those two levels (in this case, -d 65). Or, you can let slapd do the math, (e.g. -d 1 -d 64). Consult <ldap_log.h> for more details.

Note: slapd must have been compiled with --enable-debug, which is the default, for any debugging information other than the stats and stats2 levels to be available as options.

7.2. Starting slapd

In general, slapd is run like this:

        /usr/local/libexec/slapd [<option>]*

where /usr/local/libexec is determined by configure and <option> is one of the options described above (or in slapd(8)). Unless you have specified a debugging level (including level 0), slapd will automatically fork and detach itself from its controlling terminal and run in the background.

7.3. Stopping slapd

To kill off slapd(8) safely, you should give a command like this

        kill -INT `cat /usr/local/var/slapd.pid`

where /usr/local/var is determined by configure.

Killing slapd by a more drastic method may cause information loss or database corruption.