Silverstripe CMS needs to be installed on a web server. Content authors and website administrators use their web browser to access a web-based GUI to do their day-to-day work. Website designers and developers require access to the files on the server to update templates, website logic, and perform upgrades or maintenance.
- PHP >=7.1
- PHP extensions:
- PHP configuration:
memory_limitwith at least
- PHP extension for image manipulation: Either
- PHP extension for a database connector (e.g.
Use phpinfo() to inspect your configuration.
- MySQL >=5.6 (built-in, commercially supported)
- PostgreSQL (third party module, community supported)
- SQL Server (third party module, community supported)
- SQLite (third party module, community supported)
Default MySQL Collation
In Silverstripe CMS Recipe 4.7 and later, new projects default to the
utf8mb4_unicode_ci collation when running against MySQL, which offers better support for multi-byte characters such as emoji. However, this may cause issues related to Varchar fields exceeding the maximum indexable size:
- MySQL 5.5 and lower cannot support indexes larger than 768 bytes (192 characters)
- MySQL 5.6 supports larger indexes (3072 bytes) if the
innodb_large_prefixsetting is enabled (but not by default)
- MySQL 5.7 and newer have
innodb_large_prefixenabled by default
- MariaDB ~10.1 matches MySQL 5.6's behaviour, >10.2 matches 5.7's.
You can rectify this issue by upgrading MySQL, enabling the
innodb_large_prefix setting if available, or reducing the size of affected fields. If none of these solutions are currently suitable, you can remove the new collation configuration from
app/_config/mysite.yml to default back to the previous default collation.
Existing projects that upgrade to Recipe 4.7.0 will unintentionally adopt this configuration change. Recipe 4.7.1 and later are unaffected. See the release notes for more information.
Connection mode (sql_mode) when using MySQL server >=5.7.5
In MySQL versions >=5.7.5, the
ANSI sql_mode setting behaves differently and includes the
ONLY_FULL_GROUP_BY setting. It is generally recommended to leave this setting as-is because it results in deterministic SQL. However, for some advanced cases, the sql_mode can be configured on the database connection via the configuration API (see
MySQLDatabase::$sql_mode for more details.) This setting is only available in Silverstripe CMS 4.7 and later.
SilverStripe needs to handle a variety of HTTP requests, and relies on the hosting environment to be configured securely to enforce restrictions. There are secure defaults in place for Apache, but you should be aware of the configuration regardless of your webserver setup.
The webroot of your webserver should be configured to the
Projects created prior to SilverStripe 4.1 might be using the main project
folder as the webroot. In this case, you are responsible for ensuring
access to system files such as configuration in
*.yml is protected
from public access. We strongly recommend switching to more secure
hosting via the
public/. See 4.1.0 upgrading guide.
SilverStripe needs write access for the webserver user to
and read access for that user on everything else in your webroot.
SilverStripe allows CMS authors to upload files into the
which should be served by your webserver. No PHP execution should be allowed in this folder.
This is configured for Apache by default via
The file is generated dynamically during the
Additionally, access is whitelisted by file extension through a
dynamically generated whitelist based on the
(see File Security).
This whitelist uses the same defaults configured through file upload
through SilverStripe, so is considered a second line of defence.
Files can be kept in draft stage,
and access restricted to certain user groups.
These files are stored in a special
.protected folder (defaulting to
Requests to files in this folder should be denied by your webserver.
Requests to files in the
are routed to PHP by default when using Apache, through
If you are using another webserver, please follow our guides to ensure a secure setup.
See Developer Guides: File Security for details.
For additional security, we recommend moving the
.protected/ folder out of
This removes the possibility of a misconfigured webserver accidentally exposing
these files under URL paths, and forces read access via PHP.
This can be configured via .env variable,
relative to the
The resulting folder structure will look as follows:
.protected/ <hash>/my-protected-file.txt public/ index.php assets/ my-public-file.txt vendor/ app/
Don't forget to include this additional folder in any syncing and backup processes!
Building, Packaging and Deployment
It is common to build a SilverStripe application into a package on one environment (e.g. a CI server), and then deploy the package to a (separate) webserver environment(s). This approach relies on all auto-generated files required by SilverStripe to be included in the package, or generated on the fly on each webserver environment.
The easiest way to ensure this is to commit auto generated files to source control. If those changes are considered too noisy, here's some pointers for auto-generated files to trigger and include in a deployment package:
public/_resources/: Frontend assets copied from the (inaccessible)
vendor/folder via silverstripe/vendor-plugin. See Templates: Requirements.
public/_graphql/: Schema and type definitions required by CMS and any GraphQL API endpoint. Generated through silverstripe/graphql v4. Triggered by
dev/build, or GraphQL Schema Build.
- Various recipes create default files in
composer updatevia silverstripe/recipe-plugin.
Web Worker Concurrency
It's generally a good idea to run multiple workers to serve multiple HTTP requests to SilverStripe concurrently. The exact number depends on your website needs. The CMS attempts to request multiple views concurrently. It also routes protected and draft files through SilverStripe. This can increase your concurrency requirements, e.g. when authors batch upload and view dozens of draft files in the CMS.
When allowing upload of large files through the CMS (through PHP settings), these files might be used as protected and draft files. Files in this state get served by SilverStripe rather than your webserver. Since the framework uses PHP streams, this allows serving of files larger than your PHP memory limit. Please be aware that streaming operations don't count towards PHP's max_execution_time, which can risk exhaustion of web worker pools for long-running downloads.
SilverStripe expects URL paths to be rewritten to
For Apache, this is preconfigured through
and expects using the
By default, these files are located in
SilverStripe can add HTTP headers to reponses it handles directly.
These headers are often sensitive, for example preventing HTTP caching for responses
displaying data based on user sessions, or when serving protected assets.
You need to ensure those headers are kept in place in your webserver.
For example, Apache allows this through
Header setifempty (see docs).
See Developer Guide: Performance
and Developer Guides: File Security for more details.
Silverstripe relies on the
Host header to construct URLs such as "reset password" links,
so you'll need to ensure that the systems hosting it only allow valid values for this header.
See Developer Guide: Security - Request hostname forgery.
CDNs and other Reverse Proxies
If your Silverstripe site is hosted behind multiple HTTP layers, you're in charge of controlling which forwarded headers are considered valid, and which IPs can set them. See Developer Guide: Security - Request hostname forgery.
SilverStripe is a modular system, with modules installed and updated
composer PHP dependency manager. These are usually stored in
outside of the
public/ webroot. Since many modules rely on serving frontend assets
such as CSS files or images, these are mapped over to the
public/_resources/ folder automatically.
If the filesystem supports it, this is achieved through symlinks.
Depending on your hosting and deployment mechanisms,
you may need to configure the plugin to copy files instead.
See silverstripe/vendor-plugin for details.
Silverstripe relies on various caches to achieve performant responses. By default, those caches are stored in a temporary filesystem folder, and are not shared between multiple server instances. Alternative cache backends such as Redis can be configured.
While cache objects can expire, when using filesystem caching the files are not actively pruned. For long-lived server instances, this can become a capacity issue over time - see workaround.
The default installation includes silverstripe/errorpage,
which generates static error pages that bypass PHP execution when those pages are published in the CMS.
Once published, the static files are located in
public/.htaccess file is configured to have Apache serve those pages based on their HTTP status code.
Other webservers (Nginx, IIS, Lighttpd)
Serving through webservers other than Apache requires more manual configuration,
since the defaults configured through
.htaccess don't apply.
Please apply the considerations above to your webserver to ensure a secure hosting environment.
In particular, configure protected assets correctly to avoid exposing draft or protected files uploaded through the CMS.
There are various community supported installation instructions for different environments. Nginx is a popular choice, see Nginx webserver configuration.
SilverStripe is known to work with Microsoft IIS, and generates
web.config files by default
(see Microsoft IIS and SQL Server configuration).
Additionally, there are community supported guides for installing SilverStripe on various environments:
- Hosting via Bitnami: In the cloud or as a locally hosted virtual machine
- Vagrant/Virtualbox with CentOS
- macOS with Homebrew
- macOS with MAMP
- Windows with WAMP
- Vagrant with silverstripe-australia/vagrant-environment
- Vagrant with BetterBrief/vagrant-skeleton
PHP Requirements for older SilverStripe releases
SilverStripe's PHP support has changed over time and if you are looking to upgrade PHP on your SilverStripe site, this table may be of use:
|SilverStripe Version||PHP Version||More information|
|3.0 - 3.5||5.3 - 5.6||requirements docs|
|3.6||5.3 - 7.1|
|3.7||5.3 - 7.3||changelog|
|4.0 - 4.4||5.6+|
CMS browser requirements
SilverStripe CMS supports the following web browsers:
- Google Chrome
- Internet Explorer 11
- Microsoft Edge
- Mozilla Firefox
We aim to provide satisfactory experiences in Apple Safari. SilverStripe CMS works well across Windows, Linux, and Mac operating systems.
End user requirements