Résoudre l’erreur KCC d’un domaine active directory

Si vous avez ces messages d’erreurs dans le journal d’événement de votre serveur.

ActiveDirectory_DomainService 1865 “The Knowledge Consistency Checker (KCC) was unable to form a complete spanning tree network topology. As a result, the following list of sites cannot be reached from the local site.”

ActiveDirectory_Domain_Service 1311 “The Knowledge Consistency Checker (KCC) has detected problems with the following directory partition.”

ActiveDirectory_Domain_Service 1566 “All directory servers in the following site that can replicate the directory partition over this transport are currently unavailable.”

DNS-Server-Service 4013 “The DNS server is waiting for Active Directory Domain Services (AD DS) to signal that the initial synchronization of the directory has been completed.”

Dans un premier temps, vérifier la communication entre vos serveurs ADDS à l’aide d’un ping par exemple. Puis si vous avez un pare-feu entre les deux vérifiez si il n’y a pas de DENY, les principaux ports DNS UDP (53), NETLOGON TCP (137 à 138).

Voir : Active Directory and Active Directory Domain Services Port Requirements

Commandes utiles :

epadmin /syncall /AdePq

• Performs a synchronization for a server with all of its replication partners, the modifiers help in performing the sync in a multisite environment

Repadmin /replsum

• Summarizes the state of replication of the forest

Repadmin /kcc *

• Forces a recalculation of the topology, has the effect of rebuilding the automatically created partner connections in Sites and Services

Dcdiag /test:Connectivity

• dcdiag over all is great, but using the /test modifier you are able to run only specific tests as needed

Solution :

1. Ouvrez une invite de commande (CMD) en tant qu’administrateur.
2. Exécutez ces lignes de commandes

repadmin /kcc *

repadmin /syncall.

Ne pas redémarrer vos serveurs pendant la réplication, surveiller le journal d’événement.

Je vous conseille de laisser passer 24h avant d’effectuer un redémarrage de vos serveurs.