Important Upgrade Notes¶

v5.38 adds fixes for some of the incorrect mention counts and unreads around threads and channels since the introduction of Collapsed Reply Threads (Beta). This fix is done through a SQL migration, and it may take several minutes to complete for large databases. The fixCRTChannelMembershipCounts fix takes 1 minute and 20 seconds for a database containing approximately 4 million channel memberships and about 130,000 channels. The fixCRTThreadCountsAndUnreads fix takes about 3 minutes and 30 seconds for a database containing 56367 threads, 124587 thread memberships, and 220801 channel memberships. These are on MySQL v5.6.51.

v5.37.0

The platform binary and “–platform” flag have been removed. If you are using the “–platform” flag or are using the platform binary directly to run the Mattermost server application via a systemd file or custom script, you will be required to use only the mattermost binary.

v5.37 adds support for emoji standard v13.0. If you have added a custom emoji in the past that uses one of the new system names, then it is going to get overwritten by the system emoji. The workaround is to change the custom emoji name.

v5.36.0

Gossip clustering mode is now in General Availability and is no longer available as an option. All cluster traffic will always use the gossip protocol. The config setting UseExperimentalGossip has no effect and has only been kept for compatibility purposes. The setting to use gossip has been removed from the System Console. Note: For High Availability upgrades, all nodes in the cluster must use a single protocol. If an existing system is not currently using gossip, one node in a cluster can’t be upgraded while other nodes in the cluster use an older version. Customers must either use gossip for their High Availability upgrade, or customers must shut down all nodes, perform the upgrade, and then bring all nodes back up.

v5.35.0

Due to the introduction of backend database architecture required for upcoming new features, Shared Channels and Collapsed Reply Threads, the performance of the migration process for the v5.35 release (May 16, 2021) has been noticeably affected. Depending on the size, type, and version of the database, longer than usual upgrade times should be expected. This can vary from a couple of minutes (average case) to hours (worst case, MySQL 5.x only). A moderate to significant spike in database CPU usage should also be expected during this process. More details on the performance impact of the migration and possible mitigation strategies are provided here.

v5.35.0 introduces a new feature to search for files. Search results for files shared in the past may be incomplete until a content extraction command is executed to extract and index the content of files already in the database. Instances running Elasticsearch or Bleve search backends will also need to execute a Bulk Indexing after the content extraction is complete. Please see more details in this blog post.

v5.33.0

Deleting a reaction is now a soft delete in the Reactions table. A schema update is required and may take up to 15 seconds on first run with large data sets.

v5.32.0

ExperimentalChannelOrganization, EnableXToLeaveChannelsFromLHS, CloseUnusedDirectMessages, and ExperimentalHideTownSquareinLHS settings are only functional if the Legacy Sidebar (EnableLegacySidebar) is enabled since they are not compatible with the new sidebar experience. ExperimentalChannelSidebarOrganization has been deprecated, since the new sidebar is now enabled for all users.

A breaking change was introduced when upgrading the Go version to v1.15.5 where user logins fail with AD/LDAP Sync when the certificate of the LDAP Server has no Subject Alternative Name (SAN) in it. Creating a new certificate on the AD/LDAP Server with the SAN inside fixes this.

v5.31.0

For Mobile Apps v1.42.0+, the minimum server version is set to 5.31.3 as 5.31.3 fixed an issue where the server version was reported as v5.30.0.

Disabled the xmlsec1-based SAML library in favor of the re-enabled and improved SAML library.

In-product notices have been introduced to keep System Admins and end users informed of the latest product enhancements available in new server and desktop versions. Learn more about in-product notices and how to disable them in our documentation.

v5.27.0

Disabled the xmlsec1-based SAML library in favor of the re-enabled and improved SAML library.

An EnableExperimentalGossipEncryption option was added under ClusterSettings. If this is set to true, and UseExperimentalGossip is also true, all communication through the cluster using the gossip protocol will be encrypted. The encryption uses AES-256 by default, and it is not kept configurable by design. However, if one wishes, they can set the value in Systems table manually for the ClusterEncryptionKey row. A key is a byte array converted to base64. It should be either 16, 24, or 32 bytes to select AES-128, AES-192, or AES-256.

To update the key, one can execute: UPDATE Systems SET Value='<value>' WHERE Name='ClusterEncryptionKey'; in MySQL and UPDATE systems SET value='<value>' WHERE name='ClusterEncryptionKey' for PostgreSQL.

For any change in this config setting to take effect, the whole cluster must be shut down first. Then the config change made, and then restarted. In a cluster, all servers either will completely use encryption or not. There cannot be any partial usage.

PostgreSQL ended long-term support for version 9.4 in February 2020. From v5.26 Mattermost officially supports PostgreSQL version 10 as PostgreSQL 9.4 is no longer supported. New installs will require PostgreSQL 10+. Previous Mattermost versions, including our current ESR, will continue to be compatible with PostgreSQL 9.4. PostgreSQL 9.4 and all 9.x versions are now fully deprecated in our v5.30 release (December 16, 2020). Please follow the instructions under the Upgrading Section within the PostgreSQL documentation.

Disabled the xmlsec1-based SAML library in favor of the re-enabled and improved SAML library.

The mattermost_http_request_duration_seconds histogram metric (in Enterprise Edition) has been removed. This information was already captured by mattermost_api_time, which also contains the API handler name, HTTP method, and the response code.

As an example, if you are using rate(mattermost_http_request_duration_seconds_sum{server=~"$var"}[5m]) /   rate(mattermost_http_request_duration_seconds_count{server=~"$var"}[5m]) to measure average call duration, it needs to be replaced with sum(rate(mattermost_api_time_sum{server=~"$var"}[5m])) by (instance) /   sum(rate(mattermost_api_time_count{server=~"$var"}[5m])) by (instance).

On mobile apps, users will not be able to see LDAP group mentions (E20 feature) in the autocomplete dropdown. Users will still receive notifications if they are part of an LDAP group. However, the group mention keyword will not be highlighted.

v5.22.0

Due to fixing performance issues related to emoji reactions, the performance of the upgrade has been affected in that the schema upgrade now takes more time in environments with lots of reactions in their database. These environments are recommended to perform the schema migration during low usage times and potentially in advance of the upgrade. Since this migration happens before the Mattermost server is fully launched, non-High Availability installs will be unreachable during this time.

The migration is a single line of SQL and can be applied directly to the database through the MySQL/PSQL command line clients if you prefer to decouple this from restarting the Mattermost server. It is fully backwards compatible so the schema change can be applied to any previous version of Mattermost without issue. During the time the schema change is running (~30s per million rows in the Reactions table), if end users attempt to react to posts, the emoji reactions will not load for end users.

MySQL: ALTER TABLE Reactions DROP PRIMARY KEY, ADD PRIMARY KEY (PostId, UserId, EmojiName);

Postgres: ALTER TABLE reactions DROP CONSTRAINT reactions_pkey, ADD PRIMARY KEY (PostId, UserId, EmojiName);

Direct access to the Props field in the model.Post structure has been deprecated. The available GetProps() and SetProps() methods should now be used. Also, direct copy of the model.Post structure must be avoided in favor of the provided Clone() method.

v5.21.0

Honour key value expiry in KVCompareAndSet, KVCompareAndDelete, and KVList. We also improved handling of plugin key value race conditions and deleted keys in Postgres.

v5.20.0

Any pre-packaged plugin that is not enabled in the config.json will no longer install automatically, but can continue to be installed via the Plugin Marketplace.

v5.19.0

LockTeammateNameDisplay setting was moved to Enterprise Edition E20 as it was erroneously available in Team Edition and Enterprise Edition E10.

The Go module path of mattermost-server was changed to comply with the Go module version specification. Developers using Go modules with mattermost-server as a dependency must change the module and import paths to github.com/mattermost/mattermost-server/v5 when upgrade this dependency to v5.18. See https://blog.golang.org/v2-go-modules for further information.

Removed the ability to change the type of a channel using the PUT /channels/{channel_id} API endpoint. The new PUT /channels/{channel_id}/privacy endpoint should be used for that purpose.

The Mattermost Desktop v4.3.0 release includes a change to how desktop notifications are sent from non-secure URLs (http://). Organizations using non-secure Mattermost Servers (http://) will need to update to Mattermost Server versions 5.16.0+, 5.15.1, 5.14.4 or 5.9.5 (ESR) to continue receiving desktop notifications when using Mattermost Desktop v4.3.0 or later.

v5.14.0

Webhooks are now only displayed if the user is the creator of the webhook or a System Administrator.

v5.12.0

If your plugin uses the DeleteEphemeralMessage plugin API, update it to accept a postId string parameter. See documentation to learn more.

ExperimentalEnablePostMetadata setting was removed. Post metadata, including post dimensions, is now stored in the database to correct scroll position and eliminate scroll jumps as content loads in a channel.

v5.11.0

If your integration uses Update.Props == nil to clear Props, this will no longer work in 5.11+. Instead, use Update.Props == {} to clear properties.

This change was made because Update.Props == nil unintentionally cleared all Props, such as the profile picture, instead of preserving them.

v5.9.0

If DisableLegacyMfa setting in config.json is set to true and multi-factor authentication is enabled, ensure your users have upgraded to mobile app version 1.17 or later. Otherwise, users who have MFA enabled may not be able to log in successfully.

If the setting is not defined in the config.json file, the DisableLegacyMfa setting is set to false by default to ensure no breaking changes.

We recommend setting DisableLegacyMfa to true for additional security hardening.

v5.8.0

The local image proxy has been added, and images displayed within the client are now affected by the AllowUntrustedInternalConnections setting. See documentation for more details if you have trouble loading images.

If EnablePublicChannelsMaterialization setting in config.json is set to false, an offline migration prior to upgrade may be required to synchronize the materialized table for public channels to increase channel search performance in the channel switcher (CTRL/CMD+K), channel autocomplete (~), and elsewhere in the UI. Use the following steps:

1. Shut down your application servers.

2. Connect to your Mattermost database.

3. Execute the following queries:

DELETE FROM PublicChannels;
INSERT INTO PublicChannels
    (Id, DeleteAt, TeamId, DisplayName, Name, Header, Purpose)
SELECT
    c.Id, c.DeleteAt, c.TeamId, c.DisplayName, c.Name, c.Header, c.Purpose
FROM
    Channels c
WHERE
    c.Type = 'O';

The queries above rebuild the materialized PublicChannels table without modifying the authoritative Channels table.

Note that this migration is not required if the experimental PublicChannels feature was never disabled. This feature launched in Mattermost v5.4 with a temporary flag to disable should an issue arise, but nothing prompted doing so. If you did not modify this setting, there is no need to perform this migration.

In certain upgrade scenarios the new Allow Team Administrators to edit others posts setting under General then Users and Teams may be set to True while the Mattermost default in 5.1 and earlier and with new 5.4+ installations is False.

v5.2.0

Those servers upgrading from v4.1 - v4.4 directly to v5.2 or later and have Jira enabled will need to re-enable the Jira plugin after an upgrade.

v5.0.0

All API v3 endpoints are removed. See documentation to learn how to migrate your integrations to API v4.

A Mattermost user setting to configure desktop notification duration in Account Settings > Notifications > Desktop Notifications is removed.

A new config.json setting to whitelist types of protocols for auto-linking will be added. If you rely on custom protocols auto-linking in Mattermost, whitelist them in config.json before upgrading.

An unused ExtraUpdateAt field will be removed from the channel modal.

Deployments on Enterprise E20 will need to enable RunJobs in the config.json and allow the permissions migration to complete before using Team Override Schemes.

Server logs written to System Console > Logs and to the mattermost.log file specified in System Console > Logging > File Log Directory now use JSON formatting. If you have built a tool that parses the server logs and sends them to an external system, make sure it supports the JSON format.

Those servers with SAML authentication enabled should upgrade during non-peak hours. SAML email addresses are migrated to lowercase to prevent login issues, which could result in longer than usual upgrade time.

v4.9.0

To improve the production use of Mattermost with Docker, the Docker image is now running a as non-root user and listening on port 8000. Please read the upgrade instructions for important changes to existing installations.

The behavior of the config.json setting PostEditTimeLimit has been updated to accomodate the migration to a roles based permission system. When post editing is permitted, set "PostEditTimeLimit": -1 to allow editing anytime, or set "PostEditTimeLimit" to a positive integer to restrict editing time in seconds. If post editing is disabled, this setting does not apply.

v4.6.2

If using Let’s Encrypt without a proxy server, forward port 80 through a firewall, with the Forward80To443 config.json setting set to true to complete the Let’s Encrypt certification.

LDAP sync now depends on email. Make sure all users on your AD/LDAP server have an email address or that their account is deactivated in Mattermost.

By default, user-supplied URLs such as those used for Open Graph metadata, webhooks, or slash commands will no longer be allowed to connect to reserved IP addresses including loopback or link-local addresses used for internal networks.

This change may cause private integrations to break in testing environments, which may point to a URL such as http://127.0.0.1:1021/my-command.

If you point private integrations to such URLs, you may whitelist such domains, IP addresses, or CIDR notations via the AllowedUntrustedInternalConnections config setting in your local environment. Although not recommended, you may also whitelist the addresses in your production environments. See documentation to learn more.

Push notification, OAuth 2.0 and WebRTC server URLs are trusted and not affected by this setting.

Mattermost /platform` repo has been separated to /mattermost-webapp and /mattermost-server. This may affect you if you have a private fork of the /platform repo. More details here.

v3.9.0

Old email invitation links, password reset links, and email verification links will no longer work due to a security change. Team invite links copied from the Team Invite Link dialog are not affected and are still valid.

You need to verify settings in the System Console due to a security-related change.

1. Go to the the GENERAL section of the System Console

2. Click Logging

3. Make sure that the File Log Directory field is either empty or has a directory path only. It must not have a filename as part of the path.

v3.6.0

Update the maximum number of files that can be open.

On RHEL6 and Ubuntu 14.04:

• Verify that the line limit nofile 50000 50000 is included in the /etc/init/mattermost.conf file.

On RHEL7 and Ubuntu 16.04:

• Verify that the line LimitNOFILE=49152 is included in the /etc/systemd/system/mattermost.service file.

v3.4.0

If public links are enabled, existing public links will no longer be valid. This is because in earlier versions, existing public links were not invalidated when the Public Link Salt was regenerated. You must update any place where you have published these links.