SCCM 2007 Components are critical to perform its activities and if any of the component is stopped(some components start when they have work to do like Discovery methods are only start if discovery runs) ,you may see issues respective to that Component(Ex: Distribution Manager stopped,nothing process about packages).
Some of the components that involved in Site-Site Replication and ensure these components are running before you Dig more into Site-site replication issues.
I do check these components if I see any replication issues on my Child sites and follow the troubleshooting Steps.
Offer Manager replicates advertisements to child sites. Creates a file named SMS_<sitecode>\inboxes\replmgr.box\outbound\<Priority>_<ObjectID>.RPT.
Replication Manager then creates a mini-job in SMS\inboxes\schedule.boz\ by using a sequentially numbered job file.
Distribution Manager manages the replication of package definition files and package source files from parent to child sites. For package definition file replication, Distribution Manager creates a package (.pkg) file in SMS_sitecode\Inboxes \Replmgr.box\Outbound\Normal\<ObjectID>.RPT. Replication Manager then creates a mini-job in SMS\Inboxes\Schedule.box\ by using a sequentially numbered job file.
Distribution Manager also manages package status and creation and replication of package status messages.
|COLLECTION EVALUATOR||Collection Evaluator on child primary sites inputs collection rules in a .psd file, replicates collection definition or deleted notifications to each child site using normal replication processes - replmgr, scheduler, sender. On secondary sites, collection rules that are replicated to secondary sites are stored in a *clf file.|
|INVENTORY DATALOADER||Hardware Inventory .mif files are forwarded from child sites to their parent using normal replication processes – replmgr, scheduler, and sender. Site attach - child site converts all inventory data in its site database to .mif files and this data then replicates up the parent chain.|
|DESPOOLER||Despooler processes replication instruction files from the current site as well as parent and child sites. Despooler reads the file instruction files in order to determine what action to take.|
|DISCOVERY DATA MANAGER||All child sites forward discovery data to their parents. Secondary site DDR processing - Secondary sites send all DDRs to their parent for processing. After processing is complete there, the parent site replicates a *.pdr file back down to the secondary site server and replicates the .ddr to its parent site|
|INVENTORY PROCESSOR||All child sites forward inventory data to their parents. Secondary sites forward inventory data to their parent site by using standard replication processes.|
Hierarchy Manager replicates the heartbeat site control file up the site hierarchy and ensures that each parent site’s database contains the up-to-date configuration.
Site Control files replicated to child sites use normal replication paths to transmit the data to the child site.. However, Despooler at the child site bypasses Replication Manager and moves the new site control file directly to Hierarchy Manager.
Secondary site installation initiated at parent site - Hierarchy Manager creates a mini-job to send a Setup package to the secondary site server. When installation is selected, Hierarchy Manager starts a thread to compress the installation files into the \Inboxes\Hman.box\Sitepkg.p*folder on the parent server; then creates a mini-job for Scheduler (Replication Manager) to replicate this site installation package. *.ct2 on the new site is replicated back to the back to the parent site. Secondary site’s parent site replicates to its parents
|SOFTWARE INVENTORY PROCESSOR||
The Software Inventory Processor (SinvProc) reads inventory information in the form of .SIC (full report) and SID (delta report) files from the\inboxes\auth\sinv.box\ inbox, and the \inboxes\sinv.box inbox. It parses the file, and updates the database with the new inventory information.
The reports may also contain collected files, in which case the files are written to \inboxes\sinv.box\FileCol\. If running on a child site, the inventory data is packaged into a set of binary files and replicated to the parent. Secondary sites replicate inventory data to their parent site where the data is added to the site database. This inventory data is further replicated from child to parent sites.
|SITE CONTROL MANAGER||Site Control Manager replicates site control files between sites. Changes made at a parent site are replicated to child sites as .CT1 files. After child sites process the parent sites changes, the child site replicates a .CT2 file back to its parent site.|
|OBJECT REPLICATION MANAGER||
Object Replication Manager (ORM) provides the infrastructure to do basic site to site replication of various kinds of SMS objects.
· ORM is responsible for creation of replication objects on the parent site. It has a mechanism to register various object types for replication. After it is registered, the database table for the object on the parent site is monitored. If there are changes to the object, different files (depending on object type) get dropped into the \inboxes\objmgr\ folder and the parent site thread processes these objects and serializes them to files that constitute replication jobs. It then makes a call to replication manager to replicate these changed objects to all sites. Object Replication Manager uses transaction based replication (transaction IDs).
· On the child site, when replication manager drops incoming replication files into the \inboxes\objmgr\ folder, ORM processes these files and calls into the appropriate base classes to insert, delete, or update the appropriate object on the child site.
The different types of objects that Object Replication Manager replicates in Configuration Manager 2007 are the following:
· Configuration Items
· Update Sources
· Software Update Categories
· SDM Packages
· EULAs (End User License Agreements)
· Device Setting Items
|CI ASSIGNMENT MANAGER||
CI Assignment Manager runs on every primary site in the hierarchy, managing CI Assignments and replicating them to other sites. It also manages changes to CI Assignment objects such as addition and deletion of CIs and changes to CI Assignment properties.
When a new CI Assignment is added, updated or deleted, CI Assignment Manager gets notified via a database trigger. This causes it to create a new replication file for that CI Assignment and send it down to all its primary child sites. When the child site’s CI Assignment Manager receives this file it updates the database of the site accordingly.
For more information about Configuration Items see About Configuration Baselines and Configuration Items: http://msdn.microsoft.com/en-us/library/cc144216.aspx
|SMS_OFFER_STATUS_SUMMARIZER||Monitors for and gathers offer status data from advertisement status messages raised by clients. Summarized status is replicated up the site hierarchy to Advertisement Status Summarizer on the parent sites|
|SMS_SITE_SYSTEM_STATUS_SUMMARIZER||Monitors and gathers data on disk space, network accessibility and availability state for all server roles. Summarized status is replicated up the site hierarchy.|
|SMS_COMPONENT_STATUS_SUMMARIZER||Monitors and gathers component status messages and availability state for all servers. Summarized status is replicated up the site hierarchy|
|SMS_OFFER_STATUS_SUMMARIZER||Monitors for and gathers offer status data from advertisement status messages raised by clients. Summarized status is replicated up the site hierarchy.|
|SMS_STATUS_MANAGER||Monitors for status messages and applies all enabled status filter rules to each received message. This includes replication of messages up the site hierarchy.|
For more information about Component Status ,refer Technet http://technet.microsoft.com/en-us/library/bb680477.aspx
Note: This information is taken from Configmgr 2007 Site-Site replication document from Technet blogs. To Read more about How site-Site Replication works,Dig here http://blogs.technet.com/cfs-file.ashx/__key/CommunityServer-Components-PostAttachments/00-03-34-44-65/ConfigMgr2007Site2SiteReplication.doc.