Configuration of ApacheDS with Spring

This section describes the overall structure of the server configuration, which uses Spring.

ApacheDS and Spring

There are several options to configure ApacheDS. For instance you can practically do everything programmatically if you embed the server in a Java component.

For this guide we assume a standard installation of ApacheDS run standalone, and the default mechanism to configure this deployment option is (in almost all cases) changing the file server.xml, which is located in the conf directory of your ApacheDS instance. The file is composed of bean definitions, because configuration in ApacheDS 1.5 is done with the help of the Spring Framework.

Despite the fact that the default server.xml shipped with the product is somewhat long, a quick look with the help of the Spring IDE displays that the structure is rather simple:

Most configuration tasks can be accomplished by modifying the properties of existing bean definitions, or (e.g. for a new partition) by adding new beans of certain types and wiring them to the configuration.

Note that the picture above does not show all properties available in the configuration. Only those are visible for which the default server.xml contains a value. There are more, and in case of absence the default value is chosen. Feel free to browse the file to get an impression about further options – several other features controlled by properties are commented out.

Using Apache Directory Studio for configuration

Apache Directory Studio supports creation and manipulations of these configurations files. Apache Directory Studio 1.5.0 supports the configuration file format of Apache DS 1.5.5.

ApacheDS configurable parameters

Apache Directory Server has many different configuration parameters. This page summarize all the possible parameters, and what are the default values for all of them.

The global structure is given here :

• apacheDS
  • defaultDirectoryService
  • ldapService

• ldapService
  • defaultDirectoryService
  • extendedOperationHandlers
  • saslMechanismHandlers
  • saslQop
  • saslRealms
  • tcpTransport
  • udpTransport

• defaultDirectoryService
  • defaultChangeLog
  • interceptors
    • AciAuthorizationInterceptor
    • AuthenticationInterceptor
    • ChangeLogInterceptor
    • CollectiveAttributeInterceptor
    • DefaultAuthorizationInterceptor
    • EventInterceptor
    • ExceptionInterceptor
    • KeyDerivationInterceptor
    • NormalizationInterceptor
    • OperationalAttributeInterceptor
    • PasswordPolicyInterceptor
    • ReferralInterceptor
    • ReplicationInterceptor
    • SchemaInterceptor
    • SubentryInterceptor
    • TriggerInterceptor
  • partitions
    • jdbmPartition
      • indexedAttributes
        • jdbmIndex
  • systemPartition
    • jdbmPartition
      • indexedAttributes
        • jdbmIndex
  • testEntries

• changePasswordServer
  • defaultDirectoryService
  • tcpTransport
  • udpTransport

• dnsServer
  • defaultDirectoryService
  • tcpTransport
  • udpTransport

• kdcServer
  • defaultDirectoryService
  • tcpTransport
  • udpTransport

• ntpServer
  • tcpTransport
  • udpTransport

Interceptors

We have currently 16 possible interceptors we can use in the server. It's important to understand that some of them are mandatory, and other can be activated or disabled. The interceptors order is also very important : most of them can't be moved up or down, without severely impact the server behaviour.

Here is the list of the mandatory interceptors, and the order in which they should appears in the configuration file :

The following table represents the same interceptor in the order they must appear :

Interceptor without any parameters

Most of all the interceptors don't take any paramter. The only possible configuration is to enable or disable them, simply by adding or removing them from the list of interceptors. Here is the list of those interceptors :

• AciAuthorizationInterceptor
• AuthenticationInterceptor
• ChangeLogInterceptor
• CollectiveAttributeInterceptor
• DefaultAuthorizationInterceptor
• EventInterceptor
• ExceptionInterceptor
• KeyDerivationInterceptor
• NormalizationInterceptor
• OperationalAttributeInterceptor
• PasswordPolicyInterceptor
• ReferralInterceptor
• SchemaInterceptor
• SubentryInterceptor
• TriggerInterceptor

Here is an example of configuration where the aciAuthorizationInterceptor is enabled :

AuthenticationInterceptor :

Set<Authenticator> : The list of supported Authenticators. Currently, we have Anonymous, Simple and Strong authenticators. We can just list the associated beans in the server.xml file. Here is a sample of such a configuration :

The possible values are : AnonymousAuthenticator, SimpleAuthenticator and StrongAuthenticator, out of which the SimpleAuthenticator has a possible parameter, the cache size (an integer value)

ReplicationInterceptor

This interceptor manage the replication. It has many parameters, most of them being defined in a specific clas : ReplicationConfiguration. Let's describe those parameters.

Each instance has a name, which allows multiple instances of the server to be present on the same machine, but with possible replication between them.

First, let see an example :

Here, we have set 2 replicas (instance B and C), the current instance is listening on port 10390, and we have modified the default values for logMaxAge, replicationInterval and responseTimeout.

The ReplicationConfiguration bean contains those parameters :

The peerReplicas parameter is a composite one.

This is the list of remote replicas. Each replica is defined by a name, a host address and a port. The syntax must be :
<replicaid>@<host>:<port>, like ServerAAA@10.1.2.7:1234.

Partition

The ADS server can support more than one kind of Partition, but the default is to use JDBM. Here is the associated configuration for this underlying partition.

JdbmPartition

The main class managing the backend where entries are stored and indexed.

Six kind of parameters can be configured. Here is a table presenting each of them. Only one is a composite parameter, the JdbmIndex list, which is the list of indexes we can set for this partition

Here is an example of a partition configuration

We have created the example partition, described by the "dc=example,dc=com" DN, with a cache of 100 objects.

JdbmIndex

Each JdbmIndex represent an index set on a specific attributeType. Using index is vital in LDAP if one want to get some performance boost. As a LDAP server is mainly used for reads, index all the AttributeType you will use to retrieve entries from the base.

Here are the parameters you can configure on an index

[1] Many indexes must be set on technical attributes. Right now, only OID are used for those technical attributeTypes. In a close future, we will remove them from the indexed attribute list, unless one wants to set another cache size for them
[2] In some case, an attribute value can point to many entries. For instance, the 'person' ObjectClass will point to potentially millions of entries if we manage millions of users. In this case, we don't store all the references to entries into a big hashmap, but instead we are using a secondary B-Tree to speed-up the search and modification. Usually, 512 elements stored into a page is a good guess.

Here is an example of indexed attribute configuration for a partition

We have define two indexes for the ou and uid attributeType, on top of the technical attributeTypes (all the OIDs), and the ObjectClass, obviously. The cache size is small (from 10 objects to 100 objects).

Protocols

All the supported protocols (except DHCP) are derived from the AbstractProtocolService, and all of those protocols but NTP inherit from the DirectoryBackedService.

It means that we have some common configuration shared by all the protocols. Here is the table of the AbstractProtocolService class shared parameters :

In some case, we want a protocol to be accepting connection only on UDP or only on TCP, or on both but with a different port. In these cases, we are using the following parameters, in place of the three parameters IpBackLog, IpPort, NbThreads :

TCP specific configuration :

UDP specific configuration :

And here are the DirectoryBackedService shared parameters :

Each protocol have its own configuration. The following paragraphs will describe those configurations.

ChangePasswordServer

Some documentation is available here

The ChangePassword server has the following parameters :

[1] Encryption types values

• des-cbc-crc
• des-cbc-md4
• des-cbc-md5
• des3-cbc-md5
• des3-cbc-sha1
• dsaWithSHA1-CmsOID
• md5WithRSAEncryption-CmsOID
• sha1WithRSAEncryption-CmsOID
• rc2CBC-EnvOID
• rsaEncryption-EnvOID
• rsaES-OAEP-ENV-OID
• des-ede3-cbc-Env-OID
• des3-cbc-sha1-kd
• aes128-cts-hmac-sha1-96
• aes256-cts-hmac-sha1-96
• rc4-hmac
• rc4-hmac-exp
• subkey-keymaterial
• rc4-md4
• rc4-hmac-old
• rc4-hmac-old-exp

DnsServer

KdcServer

LdapService

We have two sets of parameters : some are simple, some are composite. We will expose the full list first, then a description for every composite parameter the composite parameters are bold).

SASL configuration

Those parameters are defined when using SASL Authentication.

SaslMechanismHandlers configuration

This is a list of parameters describing the supported SASL mechanisms. Currently, the following mechanisms are supported :

• SIMPLE
• PLAIN
• CRAM_MD5
• DIGEST_MD5
• GSSAPI
• NTLM

The configuration file will be something like :

The specific parameters for each of those handlers is described here.

SaslQoP configuration

This parameter is used when the GSSAPI and DIGEST-MD5 authentication handlers are used (see RFC 2831). It contains the possible Quality of Protections :

• auth
• auth-int
• auth-conf

Here is an example of configuration in the server.xml file :

SaslRealms configuration

This parameter lists the realms serviced by this SASL host, used by DIGEST-MD5 and GSSAPI. It contains a list of host name.

Here is an example in the server.xml file :

DirectoryService configuration

This is the directory service managing all the stored information for many protocols, including LDAP, KDC, DNS and ChangePassword.

It has many parameters which can be tunned. Here is the list of all the available parameters :

Journal

Manage the Journaling system. It can be enabled or disabled, and is associated with a Store. Here is an example of configuration :

ExtendedOperationHandlers configuration

This parameter is used to list the supported extended operations. This is a highly technical parameter, and you are not likely to change it, except if you want to remove some of the extended operations for some reasons.

The syntax is simple : it's a list of all the supported classes implementing extended operations. Here is an example in the server.xml file :

As you can see, the last extended operation is commented, it won't be available into this instance of the LDAP server.

Currently, the available extended operations are :

• GracefulShutdownHandler : Handle the server shutdown
• LaunchDiagnosticUiHandler : Launch a graphical tool to look at the backend content
• StartTlsHandler : Handle the StartTLS operation (establishes a secured connection between the server and a client)
• StoredProcedureExtendedOperationHandler : Manage StoredProcedured, executing them when received.

NtpServer

There is no specific parameter for the NtpServer. The AbstractProtocolService parameters have to be used in order to configure this server. Here is an example of configuration :

We have a running NtpServer on localhost, waiting for incomming connection on port 60213, for TCP and UDP transports. 8 processing threads for each of the transport connectors will be used to process the incoming requests.

StandardThreadPool ???

LDAP Handlers

SASL Mechanism handlers

CramMd5MechanismHandler

DigestMd5MechanismHandler

GssapiMechanismHandler

NtlmMechanismHandler

PlainMechanismHandler

SimpleMechanismHandler

ADS

ReplicationConfiguration

ApacheDSJdbmPartition

Resources

• Spring Framework 1.2.x Reference Documentation