The image is based on alpine .
The Dockerfile is inspired by
NOTE: On purpose, there is no secured channel (TLS/SSL), because I believe that
this service should never be exposed to the internet, but only be used directly
by other Docker containers using the
The most simple form would be to start the application like so (however this is
not the recommended way - see below):
docker run -d -p 389:389 -e SLAPD_PASSWORD=mysecretpassword -e SLAPD_DOMAIN=ldap.example.org danielguerra/alpine-openldap
To get the full potential this image offers, one should first create a data-only
container (see "Data persistence" below), start the OpenLDAP daemon as follows:
docker run -d --name openldap --volumes-from your-data-container danielguerra/alpine-openldap
An application talking to OpenLDAP should then
--link the container:
docker run -d --link openldap:openldap image-using-openldap
The name after the colon in the
--link section is the hostname where the
OpenLDAP daemon is listening to (the port is the default port
Configuration (environment variables)
For the first run, one has to set at least the first two environment variables.
After the first start of the image (and the initial configuration), these
envirnonment variables are not evaluated again.
SLAPD_PASSWORD(required) - sets the password for the
SLAPD_DOMAIN(required) - sets the DC (Domain component) parts. E.g. if one sets
ldap.example.org, the generated base DC parts would be
SLAPD_ORGANIZATION(defaults to $SLAPD_DOMAIN) - represents the human readable
company name (e.g.
SLAPD_CONFIG_PASSWORD- allows password protected access to the
branch. This helps to reconfigure the server without interruption (read the
SLAPD_ADDITIONAL_SCHEMAS- loads additional schemas provided in the
package that are not installed using the environment variable with comma-separated
enties. As of writing these instructions, there are the following additional schemas
SLAPD_ADDITIONAL_MODULES- comma-separated list of modules to load. It will try
.ldiffiles with a corresponsing name from the
Setting up ppolicy
The ppolicy module provides enhanced password management capabilities that are
applied to non-rootdn bind attempts in OpenLDAP. In order to it, one has to load
both the schema
ppolicy and the module
-e SLAPD_DOMAIN=ldap.example.org -e SLAPD_ADDITIONAL_SCHEMAS=ppolicy -e SLAPD_ADDITIONAL_MODULES=ppolicy`
There is one additional environment variable available:
SLAPD_PPOLICY_DN_PREFIX- (defaults to
cn=default,ou=policies) sets the dn
prefix used in
value used for
olcPPolicyDefaultis derived from
$SLAPD_PPOLICY_DN_PREFIX,(dc component parts from $SLAPD_DOMAIN).
After loading the module, you have to load a default password policy, assuming you are on a host that has the client side tools installed (maybe you have to change the hostname as well):
ldapadd -h localhost -x -c -D 'cn=admin,dc=ldap,dc=example,dc=org' -w [$SLAPD_PASSWORD] -f default-policy.ldif
The contents of
default-policy.ldif should look something like this:
# Define password policy dn: ou=policies,dc=ldap,dc=example,dc=org objectClass: organizationalUnit ou: policies dn: cn=default,ou=policies,dc=ldap,dc=example,dc=org objectClass: applicationProcess objectClass: pwdPolicy cn: default pwdAllowUserChange: TRUE pwdAttribute: userPassword pwdCheckQuality: 1 # 7 days pwdExpireWarning: 604800 pwdFailureCountInterval: 0 pwdGraceAuthNLimit: 0 pwdInHistory: 5 pwdLockout: TRUE # 30 minutes pwdLockoutDuration: 1800 # 180 days pwdMaxAge: 15552000 pwdMaxFailure: 5 pwdMinAge: 0 pwdMinLength: 6 pwdMustChange: TRUE pwdSafeModify: FALSE
See the docs for descriptions
on the available attributes and what they mean.
The image exposes two directories (
VOLUME ["/etc/openldap", "/var/lib/openldap"]).
The first holds the "static" configuration while the second holds the actual
database. Please make sure that these two directories are saved (in a data-only
container or alike) in order to make sure that everything is restored after a
restart of the container.