vCloud-hosted applications are dependent on directory service. After you determine the level of dependency, performance gains are achieved by encapsulating and distributing directory servers with dependent vApps services that are offered in the vCloud.

The expiration of run-time and storage leases for vApp hosting directory services can lead to unexpected outages for dependent applications. A solution to vApp expiration is to create a separate vCloud Director organization that has indefinite leases to host services that should not expire.

Provide for isolation between any redundant directory servers hosted within vCloud. To avoid single points of failure it might be necessary to distribute directory servers over multiple provider virtual datacenters that do not share physical dependencies.