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Sun ONE Calendar Server 6.0 Administrator's Guide

Appendix D  
Using the LDAP Data Cache

This appendix describes the Sun ONE Calendar Server LDAP data cache, which ensures that LDAP data is available immediately after it has been committed, even if the LDAP directory server is configured to include a delay in the availability of committed data. Topics in this appendix include:

Considerations for Using the LDAP Data Cache

Use these guidelines to determine if your site should configure the LDAP data cache:


Master/Slave LDAP Configuration

A Master/Slave LDAP configuration includes a master (root) directory server and one or more slave (consumer or replica) directory servers. Calendar Server can access the master LDAP directory server either directly or through a slave directory server:

In this second type of configuration, problems with inaccurate LDAP data can occur because of the delay in the availability of committed LDAP data to the slave directory servers.

For example, Calendar Server commits an LDAP data change, but the new data is not available for a specific amount of time because of the delay in the master directory server updating each slave directory server. A subsequent Calendar Server client operation uses the old LDAP data and presents an out-of-date view.

If the delay in updating the slave directory servers is short (only a few seconds), clients might not experience a problem. However, if the delay is longer (minutes or hours), clients will display inaccurate LDAP data for the length of the delay.

Table D-1 lists the LDAP attributes that are affected by a delay in a master/slave LDAP server configuration where Calendar Server accesses the master LDAP directory server through a slave LDAP directory server.

Table D-1  Calendar Server LDAP Attributes Affected by Delays


LDAP Attributes Affected

Auto provisioning

icsCalendar, icsSubscribed, icsCalendarOwned, icsDWPHost

Calendar groups


Calendar creation

icsCalendarOwned, icsSubscribed

Calendar subscription


User options

icsExtendedUserPrefs, icsFirstDay, icsTimeZone, icsFreeBusy

Calendar searches


To insure that your end uses have the most recent LDAP data, configure the LDAP data cache as described in the following sections: LDAP Data Cache and LDAP Data Cache Configuration Parameters.

LDAP Data Cache

The LDAP data cache resolves the master/slave LDAP configuration problem by providing Calendar Server clients with the most recent LDAP data, even when the master directory server has not updated each slave directory server.

If the LDAP data cache is enabled, Calendar Server writes committed LDAP data to the cache database (ldapcache.db file). By default, the LDAP cache database is located in the cal_svr_base/var/opt/SUNWics5/csdb/ldap_cache directory, but you can configure a different location if you prefer.

When a client makes a change to the LDAP data for a single user, Calendar Server writes the revised data to the LDAP cache database (as well as to the slave directory server). A subsequent client operation retrieves the LDAP data from the cache database. This data retrieval applies to the following operations for a single user:

Thus, the LDAP data cache database provides for:


The LDAP data cache does not provide for:

LDAP Data Cache Configuration Parameters

Table D-2 describes the configuration parameters in the ics.conf file for the LDAP data cache.

Table D-2  LDAP Data Cache Configuration Parameters 




Enables (“yes”) or disables (“no”) the LDAP data cache. The default is “no”.


Specifies the number of seconds for the checkpoint thread to sleep. The default time is 60 seconds.


Specifies whether or not to remove the database log files after they have been processed. The default is “yes”.


Specifies the physical location of LDAP data cache database. The default is cal_svr_base/var/opt/SUNWics5/csdb/ldap_cache.


Specifies the maximum size in megabytes of the checkpoint file. The default is 10 megabytes.


Specifies the maximum number of threads for the LDAP data cache database. The default is “1000”.


Specifies the number of megabytes of shared memory. The default is 4 megabytes.


Specifies the time to live (TTL) in seconds for an LDAP data cache entry. The default is 3600 seconds (1 hour).


Specifies whether or not to log the access to the LDAP data cache and to print statistics in the log file. The default is “no”.

Note This parameter applies only to debug mode.


Specifies the interval in seconds when each statistics report is written to the log file. The default is 1800 seconds (30 minutes).


Specifies the interval in seconds between each database cleanup. The default is 1800 seconds (30 minutes).



If Calendar Server or the server where Calendar Server is running is not properly shut down, it is recommended that you manually delete all files in the ldap_cache directory to avoid any database corruption that might cause problems during a subsequent restart.

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