Managing User Accounts
Application Center uses the group accounts and user accounts described in the following sections.
Caution Do not delete these accounts. Doing so will cause Application Center to malfunction.
ACA_ machine_name: used for administrative operations.
ACL_ machine_name: the local utility account used by an Application Center member. It is used for administrative work related to the member, such as writing event log information to the Application Center log. The account is a member of the ACA_ machine_name group.
ACC_ machine_name: a cluster controller account that is created on each cluster member. This account is used to manage cluster communication—for authentication across members, to replicate content, and to administer cluster members. The account is a member of the ACA_ machine_name group.
Note When another member is promoted to cluster controller, the account name is not changed.
IUSR_ machine_name: IIS uses this Windows 2000 local account to authenticate anonymous users on the Web site. This account is not used in a cluster and is kept for backwards compatibility only.
IUSR_ controller_name: used by the cluster instead of IUSR_ machine_name. It is replicated from the cluster controller to each new member and provides a single, cluster-wide, account for anonymous access.
Note The account name does not change when another member is promoted to cluster controller. Also, if a member is removed from the cluster, its IUSR_ controller_name account will continue to be the anonymous access account.
Caution It is not recommended that you change the anonymous access account for IIS on a cluster after adding members. Changing the anonymous access account for IIS on the controller can cause authentication failures. If you must change the credentials for the anonymous access account, specify a domain account to prevent this from occurring. If you change the credentials to a non-domain account, you must manually add the local account on each member.
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