Information for: DEVELOPERS   PARTNERS   SUPPORT

Modules to use with caution on Cloud Platform

The following Drupal modules can be used on Cloud Platform, but may require additional configuration or can involve use cases which can cause issues:

Note

For information about applications and modules that are incompatible with Cloud Platform, see Modules and applications incompatible with Cloud Platform.

Module/App Issue/Resolution
Adaptive Image Exercise some care when using this module because it may have issues storing image derivatives when caching is turned on. When this module is in use, users who visit a page directly after a cache clear will set the image size for that page and that image size is used for all visitors, regardless of what their browser is.
Advanced CSS/JS Aggregation This module may be beneficial for simpler sites. However, it can be problematic for complex sites that make extensive use of Drupal libraries where multiple aggregates are generated. If implemented at the edge layer, HTTP/2 reduces the value of aggregation.
Authcache This requires an evaluation of performance issues versus application complexity. Caching pages or blocks is often a better option. This module can significantly increase the size of your page cache.
Bean Specifically, we recommend against the use of bean_entitycache. When combined with the Memcache module, its behavior is unpredictable, and its use can have a negative performance impact on your application.
CAS Check the Check with the CAS server to see if the user is already logged in setting. This requires session cookies to be set, preventing Varnish® from caching pages. Acquia recommends using the Bakery module or SimpleSAML as an alternative.
Contact Importer Issue due to its reliance on Open Inviter. Create a symlink to your private files area.
Contact Storage Export The Contact Storage Export module fails to generate full results when executing a contact form export from a multi-server production environment. Acquia recommends using the patch described in issue 2996037 on Drupal.org.
DBLog Using Drupal core’s DBLog module can cause performance issues for high-traffic applications. Instead, Acquia recommends using syslog.
DB Maintenance Using this module improperly can potentially cause slowdowns or outages. If you believe that your application has tables that need optimizing, open a ticket with Acquia Support.
Devinci This module does not include settings for the Acquia Remote Administration environment.
Dropzonejs

When uploading files with the dropzonejs module (packaged with Acquia CMS) to an application with several web infrastructure served by a single load balancer, the web infrastructure that processes the form submission may not be the web infrastructure that received the temporary file in the AJAX request. Upload files through the /media/add interface instead. Alternately, configure Drupal’s temporary files directory to use:

/mnt/gfs/{$_ENV['AH_SITE_GROUP']}. {$_ENV['AH_SITE_ENVIRONMENT']}/tmp

For more information, see Setting the temporary files directory in settings.php.

Elysia Cron Elysia Cron requires careful setup. Acquia Support has seen implementations of this module that call some hooks too frequently, causing performance problems significant enough to take a production application down.
Filefield Sources Using this module on Cloud Platform causes issues with Acquia Remote Administration services. If you are using this module, it conflicts with the Stage File proxy module, and you will not be able to see images on your RA environment.
Honeypot This has a time-based session variable that can make pages uncacheable by Drupal or Varnish caches. If you don’t use this setting, cache should be unaffected.
HTML Purifier Create a symlink to your private files area.
HTTPRL May require some special configuration to use on Cloud Platform, or it can generate errors. Learn more.
Internal Page Cache

The Internal Page Cache module is enabled by default on Drupal 9 or later. The module is not required for Cloud Platform subscribers, as Varnish provides a more robust caching solution. Disabling this module reduces complexity and makes it easier to troubleshoot caching-related issues.

Note: With the Internal Page Cache module disabled, you can still configure a cache time on Drupal under Configuration -> Performance, and Acquia’s Varnish will honor this cache time.

Lightweight Directory Access Protocol (LDAP) LDAP alone without SSO can work on Cloud Platform. SSO requires NTLM (NT LAN Manager) support, which is an Apache module that Acquia does not currently support.
Link Checker The Link Checker module can sometime cause timeouts when cron is run.
Node view count This statistics module can be configured to count each node visit, which can trigger multiple database writes. This behavior can cause serious performance issues with the database—use caution when configuring this on high traffic websites.
OptimizeDB Using this module improperly can potentially cause slowdowns or outages. If you feel your site has tables that need optimizing, contact Acquia Support.
Print If not properly secured, this module can open up your application to being abused as a spam relay. If you use this module, be sure to configure it so that anonymous users cannot send email.
Quick Tabs When a page loads, QuickTabs also loads content a user does not immediately see. It creates additional links, which can cause web crawlers to visit the page additional times (2-n times), and this can cause slowdowns. It also can consume extra resources when in “AJAX Mode” by potentially generating multiple simultaneous requests to the back end to fetch tab content.
Radioactivity This module requires that memcache infrastructure be hard-coded in a separate configuration file, which directly conflicts with Acquia’s high availability services. Acquia’s platform dynamically modifies available memcache infrastructure, and hard-coded infrastructure can cause application outages.
reCAPTCHA Require session cookies to be set, preventing Varnish from caching pages.
Redirect 403 to User Login This may cause issues with anonymous session cookies. Disable the Access denied. You must log in to view this page. checkbox in the module settings.
Search 404 This useful module triggers a search when a user lands on a 404 page. This is best used with Fast 404 to prevent missing files from also triggering a search.
SimpleSAMLphp Authentication This module requires careful preparation. Without careful preparation, you can break your website. For more information, see Using SimpleSAMLphp with Acquia products.
Statistics Using Drupal core’s statistics module can cause performance issues for high-traffic applications.
TCPDF Create a symlink to your private files area.
Views Filter Harmonizer After caching the first page visited by an anonymous user, this module sets a session cookie to store the previously visited path (including contextual filter arguments), and prevents Varnish from caching any subsequent page visits. You can install the Session Cache API module to store the session information in a method compatible with Varnish. For more information, see the Session Cache API documentation.
Workbench Moderation This module does not work out of the box with ApacheSolr search integration. Learn more about problems and a solution.
WURFL Create a symlink to your private files area.
WYSIWYG CKFinder Create a symlink to your private files area.
Acquia Cloud Sticky Sessions Using the module can put a burden on one infrastructure in the group, and can cause performance problems for users whose sessions are directed to that infrastructure. Although the module was suggested for use on Cloud Platform, Acquia does not recommend using the module.

Additional module issues

Be aware of the following additional items as you work with Drupal modules:

  • In addition to the modules listed on this page, some modules require symlinks to work properly on Cloud Platform. For more information, see File permissions and symlinks while using Cloud Platform.
  • When you use modules that upload several files, applications with more than one web infrastructure may experience writes to different infrastructure for each uploaded file. After the upload process is complete, the module can’t locate all of the images, which causes a failure. Subscribers with a single web infrastructure for their Staging and Development environments and multiple web infrastructure for their Production environment can experience having these modules work in Staging and Development, but fail in the Production environment. Using Plupload is an option, but also review Correcting broken file uploads.