# Apache Modules Switched Off in VPS-Optimized Mode

The following Apache modules are switched off in the optimized mode:

- authn_alias
- authn_anon
- authn_dbm
- authn_default
- authz_user
- authz_owner
- authz_groupfile
- authz_dbm
- authz_default
- ldap
- authnz_ldap
- ext_filter
- mime_magic
- deflate
- usertrack
- dav_fs
- vhost_alias
- speling
- proxy_balancer
- cache
- disk_cache
- file_cache
- mem_cache
- version
- asis
- bw
- proxy_ajp
- auth_ldap
- perl
- python
- php5
- php4

The list of the modules can vary depending on the operating system distribution and architecture. When Plesk is installed and the optimized mode is switched on, you can check the list in the following files:

- On 32-bit operating systems - `/usr/lib/plesk-9.0/vps_optimized_aspects/apache-modules-all`
- On 64-bit operating systems - `/usr/lib64/plesk-9.0/vps_optimized_aspects/apache-modules-all`