Version 2.7 is a legacy release, and these documents are no longer being maintained.


This guide explains how to upgrade from an earlier AtoM release (including ICA-AtoM versions 1.1 to 1.3.1 or newer) to 2.7.


If you are on an earlier release of ICA-AtoM (older than 1.1), please upgrade to the latest ICA-AtoM release before following these instructions. Please see Upgrading from ICA-AtoM 1.0.x on the AtoM wiki.

While we have tried to make this document usable by readers with a broad range of technical knowledge, it may be too complex if you have no previous experience with installing web applications or using the Linux command line.

Additionally, consider disabling your web site during the upgrade. Redirect your users to a “Down for maintenance” page temporary using your web server redirection capabilities, or you can put your site in read-only mode while performing the upgrade.

Check minimum requirements

Please refer to the Minimum requirements page to make sure that your system meets all the requirements. This is especially important if you are going to be upgrading from an older version of ICA-AtoM (1.1 - 1.3.1 or later), as there will be some new dependencies that we will install as part of the upgrade process.

Read the release notes

This is the opportunity to find out what has been changed in the new release, and if there are new features, enhancements and bug fixes that may be of interest to you and your organization.

You can always find the full release notes on the AtoM wiki, here:

These often include additional details that can help you understand the purpose of the release and how best to install it.

Make sure the dependencies are updated

Since the 2.5 version, AtoM uses Elasticsearch 5.x. If you’re upgrading from an earlier version, please make sure to upgrade your Elasticsearch installation. You don’t need to backup your index data as it will be recreated from the database later in the upgrade.

You will also need to upgrade to Java 8 if the system is using a previous version, as this is a requirement for Elasticsearch 5.x.

Since the 2.6 version, AtoM requires MySQL 8.0. Bellow we’ll explain the steps needed to move and upgrade the AtoM database to properly work with that version.

Install the latest version of AtoM

Follow the instructions available in our documentation on Installation - our most comprehensive installation notes are included in the Linux section, with additional information for different operating systems and server configurations.


Remember to create a new database for this installation. When you run the web installer, it will erase your previous data if you are using the same database!

Copy your old data

At this point, you should have an 2.7 functional installation using a fresh database. Now we are going to copy the contents of the old uploads and downloads directories, as well as the database:

  1. rsync is a robust directory sync solution that we can use to copy the contents of your old uploads directory to the new one, even when both directories are in the same machine. Using the command-line, enter the following command:
$ rsync -av /var/www/icaatom_old/uploads/ /usr/share/nginx/atom/uploads/

Where icaatom_old is the name of your old installation. The path included for the new installation in this example (/usr/share/nginx/atom) is the path we recommend in our installation documentation.

Alternatively, you can just use cp:

$ cp -r /var/www/icaatom_old/uploads/ /usr/share/nginx/atom/uploads/

We’re going to want to do the same with the downloads directory as well - this is where reports, cached xml, and downloads created by the job scheduler (such as clipboard exports) are kept.

$ rsync -av /var/www/icaatom_old/downloads/ /usr/share/nginx/atom/downloads/


You may choose to delete the contents of the jobs subdirectory after copying it over - this subdirectory in the downloads folder generally contains zip files of previous exports. As such, it is temporary data and does not need to be kept. We recommend leaving the jobs subdirectory itself in place, for future exports.

If you want to delete the contents of this directory, you can use the following command:

rm -f /usr/share/nginx/atom/downloads/jobs/*

Alternatively, AtoM has a command-line task that can help remove unnecessary temporary data, including the content of the jobs subdirectory. For more information, see:

For more general information on the structure of the uploads and downloads directories in AtoM, see:

  1. Dump the contents of your old database to a temporary file, change the database name if needed:
$ mysqldump -u username -p atom > /tmp/atom_db.sql
  1. If you’re upgrading from 2.5.x or lower to 2.6.x or higher make sure your data is on utf8mb3 or utf8 (the default if you followed the installation documentation) and that you are using MySQL 8.0 as that’s a requirement since AtoM 2.6. During the upgrade task, your data will be transformed to the utf8mb4 charset and the utf8mb4_0900_ai_ci collation.
  2. Re-create the database with the new charset and collation:
$ mysql -u username -p -e "DROP DATABASE IF EXISTS atom;"
$ mysql -u username -p -e "CREATE DATABASE atom CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci;"
  1. Now, load the contents into the new database:
$ mysql -u username -p atom < /tmp/atom_db.sql

Run the upgrade task

This is perhaps the most critical step in the upgrade process. If you encounter any errors, please consult our User Forum, or if you don’t find a solution, feel free to post a question there yourself. We will also be trying to add to our FAQ as we receive feedback, to help users troubleshoot any upgrading issues encountered.

First, change the current directory:

$ cd /usr/share/nginx/atom

Now, run the upgrade-sql task:


Depending on your database size this task may use a lot of memory, so we suggest running it without a memory limit.

$ php -d memory_limit=-1 symfony tools:upgrade-sql

Restore configuration changes

If you made any change to the old AtoM instace configuration files, like setting a custom session timeout or a Google Analitycs API key, make sure to bring those changes to the new instance if you want to keep them.

Migrate translations


At this time, we are troubleshooting challenges in translation migration process from older releases to 2.7. Please see issue #5505 for progress - we will update this documentation with instructions when the tranlsation migration process has been optimized and tested. Thank you in advance for your patience.

Regenerate the digital object reference and thumbnail images (optional)

If you are upgrading from version 1.3.1 or earlier, you may want to regenerate the digital object reference and thumbnail images. The thumbnail size was smaller in 1.x, so those images will often appear fuzzy in the redesigned digital object browse. A directory naming convention has also been added to make the location of the master digital object more secure.

First, make sure you have not changed the directory (/usr/share/nginx/atom).

Now, run the regen-derivatives task:

php symfony digitalobject:regen-derivatives

For more information on this task and its available options, see: Regenerating derivatives.


If you are upgrading from version 2.6.2 or earlier, we recommend that you regenerate derivatives for any video files you may have linked or uploaded as digital objects. Prior to release 2.6.3, AtoM generated FLV derivatives as the reference display copy for video digital objects, to be used in AtoM’s previous Flash-based media player. After release 2.6.3, Flash is no longer supported, and regenerating your video derivatives will replace any FLV files with MP4 derivatives instead, ensuring they will play as expected in the new media player.

The regen-derivatives task supports a --media-type option that can be used to limit the regeneration to only videos if desired.

Rebuild search index and clear cache

To make all these changes take effect, you will need to re-index the files you’ve imported into your database, and clear the application cache.

First, rebuild the search index:


Depending on your site content this task may use a lot of memory, so we suggest running it without memory limit.

php -d memory_limit=-1 symfony search:populate

For more information and options on this task, see: Populate search index.

Then, clear your cache to remove any out-of-date data from the application:

$ php symfony cc

See Clear cache for more detailed instructions.

Check the services configuration

It’s not usual, but sometimes we introduce changes in the related services configuration, like PHP-FPM, MySQL or the AtoM worker, to improve the behaviour and performance of the application. Check the installation documentation for your operating system to find those changes.

Restart services

To ensure everything works correctly, you must restart your services after upgrading, including PHP-FPM, Memcached (if you’re using it as cache engine), and the atom-workers managed by the job scheduler.

To restart PHP-FPM:

sudo systemctl restart php7.4-fpm

Optionally, to restart Memcached:

sudo systemctl restart memcached

To restart the atom-workers:

sudo systemctl restart atom-worker  # Restarts the workers
sudo systemctl status atom-worker   # Obtains current status


For further information on configuring the job scheduler, see:

Set site base URL

One final step is to set your site’s base URL. This URL is used in XML exports to formulate absolute URLs referring to resources.

To set the site base URL:

  1. Click on the gears Admin menu in the main menu located in the header bar and select Settings.
  2. Click on or scroll down to Site information. Enter your site’s base URL into the site base URL field. If your domain is “”, for example, your base URL would normally be “”.

See also

Upgrading with a custom theme plugin

If you have developed a custom theme plugin for your application (for more information, see Create a custom theme), you may need to perform an additional step following an upgrade to ensure that all pages are styled correctly.

Bootstrap 5

Additional steps for tarball installations:

If not already installed, first download the node.js binary distributuion and export the PATH variable.

The tarball is missing three required files for this:

Copy the above files from the correct stable branch (stable/2.7.x for AtoM 2.7) of our AtoM repo.

Test that everything has been installed correctly:

$ npm install
$ npm run build

If you encounter any issues at this point, we recommend resolving them by consulting the Troubleshooting documentation before continuing.

Rebuild BS5 theme assets:

cd ~/atom
npm install
npm run build


If you are still not seeing your changes take effect, remember to clear the Symfony cache and your web browser’s cache as well!

Bootstrap 2


Bootstrap 2 themes have been deprecated and will be removed in a future release. Please consider switching to a Bootstrap 5 theme.

Specifically, The Job details page may not appear properly styled in a custom theme without an additional step. To ensure your Jobs pages properly inherit the base Dominion theming, you will need to add a call to import the jobs.less CSS file to your theme plugin’s main.less file. If you have followed our recommendations for creating a theme plugin, then you should find the main.less file for your plugin in plugins/yourThemePluginName/css/main.less. Here is an example of where you need to add a line in the ArchivesCanada theme plugin:

The line you will need to add is to import the base Jobs CSS, like so:

@import "../../arDominionPlugin/css/less/jobs.less"

Additionally, if you intend to use AtoM’s Privacy notification feature with a custom theme, and you have customized the scaffolding.less file, you may need to update it. Changes are identified here. If the theme has been customized, but the scaffolding.less file is being referenced from the arDominionPlugin theme then no modifications are required. You should also check if _header.php has been overridden in your custom theme. If so, the change highlighted in this issue needs to be added to your custom _header.php file.

Finally, if your custom theme includes modifications to the static page files homeSuccess.php and indexSuccess.php (for example, if your theme includes a custom homepage), then you will also need to ensure that when displaying the page content, render_value calls in these files are updated to render_value_html.

Specifically, your modified files should be updated to match these lines:

Recompiling after making modifications

After making any necessary updates to your custom theme, you should rebuild the CSS for the custom theme plugin, using the make command. Here is an example of rebuilding the CSS for the ArchivesCanada theme - you can swap in the name of your plugin:

make -C plugins/arArchivesCanadaPlugin

You will also want to clear the application cache, and restart PHP-FPM.

To clear the application cache:

php symfony cc

For more information, see: Clear cache.

To restart PHP-FPM:

sudo systemctl restart php7.4-fpm

If you are using Memcached with AtoM, you may also want to restart it:

sudo systemctl restart memcached


If you are still not seeing your changes take effect, remember to clear your web browser’s cache as well!

Start using the software!

Congratulations! If you are reading this, it means that you have upgraded your data successfully. Now please check that everything is working fine.


Before you put your site in production again, please take a look at your data and check that everything looks good and the data has imported correctly. We will continue to refine this documentation over time to make the upgrade process as smooth as possible, but we still think it is always important to double-check your work. Let us know if you encounter any problems!

Back to top