| This section provides a look at the main background processes that do all the heavy lifting associated with eDirectory operations. These processes are Database initialization Flat cleaner Janitor Replica sync Replica purger Limber Backlinker Schema sync Time sync
When you use the various eDirectory monitoring and repair tools, of which some were discussed in Chapter 7, "Novell eDirectory Management," and more are discussed later in this appendix, these background processes and their effects are what you monitor and repair. For this reason, it's a good idea to know a little bit about what you are looking at. Database Initialization The Database Initialization (DB Init) background process is automatically initiated whenever the file system is mounted on the eDirectory server. It also executes whenever the eDirectory database is opened or when eDirectory is reloaded. DB Init is responsible for Verifying the usability of the eDirectory database files on this server Scheduling the running of other eDirectory background processes Initializing the various global variables and data structures used by eDirectory Opening the eDirectory database files for use by the version of eDirectory running on this server
DSTrace provides the capability to monitor the DB Init process directly. Flat Cleaner The Flat Cleaner background process is used to eliminate eDirectory variables and attributes that are no longer needed by the database. Flat Cleaner is responsible for Eliminating unused bindery and external reference (X-ref) objects and/or attributes. Making sure that each of the objects in a partition replica maintained on this server has a valid public key attribute. Eliminating X-ref obituaries that have been set as purgeable. Making sure that the Server objects in partition replicas hosted on this server have maintained accurate Status and Version attributes. The Server object maintains an attribute that specifies server statusup, down, initializing, and so on. It also keeps a record of the version of eDirectory running on that server.
Flat Cleaner can be indirectly monitored through the use of Check External References in DSRepair. DSTrace also provides the capability to monitor the Janitor process directly. Janitor As its name implies, the Janitor process is responsible for routine cleanup of the eDirectory environment. Janitor is responsible for Monitoring the value of the NCP status attribute maintained in the eDirectory Server object for this server. Keeping track of the [Root]-most partition replica on the server and the overall replica depth of the server. The [Root]-most partition is the partition root object highest in the tree (closest to [Root]). Replica depth describes how many levels down from [Root] the highest partition replica hosted by that server is. Executing the Flat Cleaner process at regular intervals. Optimizing the eDirectory database at regular intervals. Reporting synthetic time use by a partition replica on the server. Synthetic time occurs when a server clock set to a future time is reset to the correct time. Any eDirectory changes made while the clock was set at the future time will bear incorrect timestamps. This problem will self-correct as long as the gap between current and synthetic time is not too large. Making sure the inherited rights for each partition root object on this server are properly maintained.
Like Flat Cleaner, Janitor can be monitored indirectly by examining the Replica Ring repair options, Time Synchronization status, and Replica Synchronization status operations with DSRepair. DSTrace also provides the ability to monitor the Janitor process directly. Replica Sync The Replica Synchronization background process is responsible for two primary tasks: Distributing modifications to eDirectory objects contained within partition replicas maintained by the eDirectory server Receiving and processing partition operations involving partition replicas hosted by the eDirectory server
DSRepair can report the status of the replica synchronization process from a number of different perspectives: DSTrace also provides the ability to monitor the Replica Synchronization process directly. Replica Purger Replica Sync schedules the execution of the Replica Purger background process. It is responsible for Purging any unused objects and/or attributes that exist in eDirectory partition replicas hosted on this server Processing obituaries for objects maintained within partition replicas hosted on this server
DSTrace also provides the ability to monitor the Replica Purger process directly, commonly referred to as Skulker. Limber After questioning several sources, it is still unclear to me why this process is named Limber, so that will remain a mystery for now. However, naming issues aside, Limber is responsible for Making sure that the eDirectory referral information for this server is properly maintained in each partition hosted on this server. Making sure that the server hosting the Master replica of the partition in which the Server object for this server resides has the correct Relative Distinguished Name (RDN) for this server. The RDN identifies a target eDirectory object's context in relation to the context of the source eDirectory object. For example, the Admin object in O = Quills would receive the following RDN for CN = jharris.OU = Education.OU = Provo.O = Quills: jharris.Education.Provo. The O = Quills is assumed from the location of the Admin object itself. Making sure the server object in eDirectory correctly reflects the operating system version and network address in use on this server. Making sure the name of the eDirectory tree in which this server resides is correctly reported. Monitoring the external reference/DRL links between this server and the partition replica that holds this server's eDirectory Server object. This is done to make sure that the eDirectory server can be properly accessed via its eDirectory object. Making sure this server's identification information is correct.
Limber can be monitored indirectly through Check External Reference, Report Synchronization Status, and Replica Ring repair options in DSRepair. DSTrace also provides the ability to monitor Limber directly. Backlinker The Backlinker background process helps maintain referential integrity within the eDirectory environment. Backlinker is responsible for Making sure that all external references (X-refs) maintained by this server are still required. Making sure that each X-ref is properly backlinked to a server that hosts a partition replica that holds the eDirectory object specified in the X-ref. Eliminating X-refs that are no longer necessary. As part of doing this, the server hosting the partition replica that holds the referenced eDirectory object is notified of the elimination of the X-ref.
Backlinker can be monitored indirectly through Check External References in DSRepair. DSTrace also provides the ability to monitor Backlinker directly. Schema Sync The Schema Sync background process is responsible for synchronizing the schema updates received by this server with other eDirectory servers. DSTrace also provides the ability to monitor Schema Synchronization directly. Time Sync Although Time Sync is not an eDirectory process, it is necessary in order to perform some partition operations such as moves and merges. The underlying time sync mechanism is not important as long as the eDirectory servers are, in fact, synchronized. However, with OES Linux, time synchronization is normally achieved with the xntp daemon. Time Sync can be monitored directly through the Time Synchronization option in DSRepair. | 