ansible-389dir-replication

This is a role that sets up replication for 389dir (aka Fedora directory server).

There is some kind of support for multi-master and some support for master-slave scenarios (see below).

Requirements

Ansible 2.3+, required for ldap_attr and ldap_entry modules.

python-ldap pip package required for those modules to work (see official Ansible docs)

For setting up TLS replication don't use Ubuntu 16.04 on server nodes (https://lists.fedoraproject.org/archives/list/389-users@lists.fedoraproject.org/thread/662AR4TV4ASSKUWJVYMRXMVND3NNX65N/).

Understanding replication

Best place to start:

• https://access.redhat.com/documentation/en-us/red_hat_directory_server/10/html/deployment_guide/designing_the_replication_process#Introduction_to_Replication-Replication_Concepts

Terms used in this role:

• master - "supplier"
• slave - "consumer"
• ro - "master->slave" replication
• rw - "master->master" replication

How to use this role

1. Make sure your 389-ds servers are already set up and you have dirmanager-level access to it
2. Decide whether you're setting up multi-master (rw) or master-slave (ro) replica
3. Pick the replication user name and password. The role creates that user for you, unless you explicitly specify not to do so (see [Role variables])
4. Pick the sample playbook and run it.

Master-master replication sample playbook

Set up full-mesh multimaster replica between all hosts in ldap-masters group.

- hosts: ldap_masters    # or localhost, depending on your group_vars setup
  become: yes
  vars:
    - ldap389_suffix: "dc=test,dc=com"               # Which area is being replicated
    - ldap389_master_authdn: "cn=root"               # User, which is able to create entries in this area
    - ldap389_master_authdn_password: "rootmaster"   # It's password, plaintext
    - ldap389_replica_type: "rw"                     # master-master fullmesh
    - ldap389_masters: "{{ groups['ldap-master'] }}" # list of servers belonging to fullmesh group
    - ldap389_replication_user: "mmreptest"          # replication user - used by 389 to authenticate against peers. This user is created by this role unless you set `ldap389_create_replication_user` to `false`
    - ldap389_replication_password: "test"           # replication user password
    - ldap389_disable_ansible_log: false             # if you set this to true (default), sensitive information will NOT be present in Ansible outputs
  roles:
    - ansible-389dir-replication

Master-slave replication

Set up full-mesh master-slave replica between all hosts in ldap-masters and ldap-slaves lists.

Sample:

 +---------------------rw-------------------+
 | +-------------------wr-----------------+ |
 | |  +------rw------+   +-----rw-----+   | |
 | |  | +----wr----+ |   |+----wr----+|   | |
 | v  | v          | v   |v          |v   | v
+--------+        +--------+        +--------+
+        + --rw-> +        + --rw-> +        +
+ Ldap01 + <-wr-- + Ldap02 + <-wr-- + Ldap03 +  <--- MASTERS, all to all, all to slaves
+        +        +        +        +        +
++++++++++        +--------+        +--------+
 |  |   |      +----+  |  |           |   | |
 |  |   |      |       |  |           |   | |
 |  +---+------+----+  |  |           |   | |
 |  +---+------+-ro-+--+--+-----------+   | |
 |  |   +------+----+--+--+---ro---------+| |
 r  |          |    |  |  |              || r
 o  |  +----ro-+    |  |  +------ro---+  || o
 |  |  |            |  |              |  || |
 |  |  |            |  |  +-----------+--++ |
 v  v  v            v  v  v           v  v  v
+--------+        +--------+        +--------+
+        + --rw-> +        + --rw-> +        +
+ Ldap04 + <-wr-- + Ldap05 + <-wr-- + Ldap06 +  <--- SLAVES, ro from every MASTER
+        +        +        +        +        +
++++++++++        +--------+        +--------+

Requires multi-master (previous paragraph) to be already set up! Role itself ASSUMES (== does not do the check) that master-master replication between ldap_masters is perfectly working.

In case you need both replications to be set up, create rw replica in one play and ro replica in the other.

- hosts: ldap_masters    # or localhost, depending on your group_vars setup
  become: yes
  vars:
    - ldap389_suffix: "dc=test,dc=com"                 # which area is being replicated
    - ldap389_master_authdn: "cn=root"                 # DN for connecting to master hosts
    - ldap389_master_authdn_password: "rootmaster"     # passwd for connecting to master hosts
    - ldap389_slave_authdn: "cn=root"                  # DN for connecting to slave hosts
    - ldap389_slave_authdn_password: "rootslave"       # passwd for connecting to slave hosts
    - ldap389_replica_type: "ro"                       # master-slave replication
    - ldap389_masters: "{{ groups['ldap-master'] }}"   # list of master hosts
    - ldap389_slaves: "{{ groups['ldap-slave'] }}"     # list of slave hosts
    - ldap389_replication_user: "msreptest"            # replication user - used by 389 to authenticate against peers. This user is created by this role unless you set `ldap389_create_replication_user` to `false`
    - ldap389_replication_password: "test"             # replication user password
    - ldap389_disable_ansible_log: false               # if you set this to true (default), sensitive information will NOT be present in Ansible outputs
  roles:
    - ansible-389dir-replication

All tasks are delegated to localhost, and thus expect the deployer instance being able to connect to remote ldap hosts.

You need to supply (the same) authdn users/passwords for master servers and the same for slave servers, in case you're setting up a ro replication.

Role variables

Mandatory (no defaults)

• ldap389_replica_type: 'ro' or 'rw'
• ldap389_replication_user: username for replication DN. The same password will be used for every host participating replication agreements.
• ldap389_replication_password: password for ldap389_replication_user
• ldap389_master_authdn: dn for connecting to LDAP master servers
• ldap389_master_authdn_password: password for ldap389_authdn
• ldap389_slave_authdn: dn for connecting to LDAP slave servers
• ldap389_slave_authdn_password: password for ldap389_slave_authdn
• ldap389_masters: list of ldap master hosts. Required in both (rw|ro) cases.
• ldap389_slaves: list of ldap slave hosts. Required for 'ro' ldap389_replica_type only.
• ldap389_suffix: suffix for which replica is going to be set up.

Optional

• ldap389_replication_tls: setup replication agreements over TLS.
• ldap389_replication_port: defaults to 389 for non-tls and 636 for tls agreements.
• ldap389_replica_bind_method: whether to use cert auth or password. Defaults to and only tested with SIMPLE.
• ldap389_changelogdir: directory where ldap changelog will be stored. Defaults to some value that is fine for both Fedora and Ubuntu.
• ldap389_disable_ansible_log: There is a ldapsearch shell command used for fetching invalid replication agreements, that reveals your authdn password unless you leave the default True. It's safe to kkeep the default value unless you're debugging some deep problem.
• ldap389_conn_schema: either ldap:// or ldaps://. This scheme is used for connections to remote servers.
• ldap389_create_replication_user: In case you set up this user elsewhere, change default true to false.

License

GPL

Author Information

• Michal Medvecky michal@medvecky.net
• Attila Szlovak aszlovak@motivum.sk
• Deutsche Telekom Pan-Net s.r.o.

Notes

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No sausages have been harmed during the development of this Ansible role.