How replication conflicts are resolved ?
There can be conflicts during replication cycle. For example, server A creates an object with a particular name at roughly the same time that Server B creates an object. with the same name. The conflict reconciliation process kicks in at the next replication cycle. The server looks for the version numbers of the updates and whichever is higher wins the conflict. If the version numbers are same, whichever attribute was changed at a later time wins the conflict. If the timestamps are equal, the guids are checked and whichever is higher wins.
If an object is moved to a parent that is now deleted, that object is placed in the lost and found` container.
If two objects with same RDN are created, then after the usual resolution process mentioned above, one of the conflicting attribute is modified with a known unique value. Between three servers, when a server receives updates from the other two, the conflict resolution is worked out at this server and repeated at the other two when they request the updates from this server.
Active Directory uses DNS for name resolution. WINS is no longer supported. DNS is a hierarchical name resolution system. DNS is one of the largest directory services. DNS nomenclature involves Zones, resource records and dynamic DNS. Zones are delegated portions of the DNS namespace that a name server maintains. A resource record is the unit of information in DNS. A zone is essentially a collection of resource records. Common record types include address record, pointer record, alias record, mail exchange record, name server record, start of authority record and service record. The last one is used by DC and AD clients to locate servers for a particular service. Service records are dependent on address records. A list of all computers running a service is maintained as A records.
There can be conflicts during replication cycle. For example, server A creates an object with a particular name at roughly the same time that Server B creates an object. with the same name. The conflict reconciliation process kicks in at the next replication cycle. The server looks for the version numbers of the updates and whichever is higher wins the conflict. If the version numbers are same, whichever attribute was changed at a later time wins the conflict. If the timestamps are equal, the guids are checked and whichever is higher wins.
If an object is moved to a parent that is now deleted, that object is placed in the lost and found` container.
If two objects with same RDN are created, then after the usual resolution process mentioned above, one of the conflicting attribute is modified with a known unique value. Between three servers, when a server receives updates from the other two, the conflict resolution is worked out at this server and repeated at the other two when they request the updates from this server.
Active Directory uses DNS for name resolution. WINS is no longer supported. DNS is a hierarchical name resolution system. DNS is one of the largest directory services. DNS nomenclature involves Zones, resource records and dynamic DNS. Zones are delegated portions of the DNS namespace that a name server maintains. A resource record is the unit of information in DNS. A zone is essentially a collection of resource records. Common record types include address record, pointer record, alias record, mail exchange record, name server record, start of authority record and service record. The last one is used by DC and AD clients to locate servers for a particular service. Service records are dependent on address records. A list of all computers running a service is maintained as A records.
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