When customer tries to create Apache webpace in POA Control Panel they see the error message 'No hosts that satisfy attributes available for provisioning'. The same error message may appear when POA is trying to create new subscription with Apache hosting resource.
However, there are Apache hosts in POA that have required provisioning attributes assigned and marked as 'Ready to Provide'.
A number of webspaces that may be created on a shared hosting server is limited by default to 100 in POA, so as a result even if host has all required attributes and is marked as 'Ready to provide' POA can not provision new webspace on host if number of webspaces is exceeded on it.
It is possible to increase a limit of number of webspaces that could be provisioned on host in POA Provider Control Panel at Service Director > Shared Hosting Manager > Apache Configuration > click on configuration > Performance Configuration tab > tune the Number of sites per IP and Number of sites per host parameters to suit your needs (0 means Unlimited).
IMPORTANT: do not increase limits to too big value, it is not possible to increase them infinitely due to memory, CPU and diskspace limitation.