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<h1id="upgrading-to-v1560"><aclass="header"href="#upgrading-to-v1560">Upgrading to v1.56.0</a></h1>
<h2id="groupscommunities-feature-has-been-deprecated"><aclass="header"href="#groupscommunities-feature-has-been-deprecated">Groups/communities feature has been deprecated</a></h2>
<p>The non-standard groups/communities feature in Synapse has been deprecated and will
be disabled by default in Synapse v1.58.0.</p>
<p>You can test disabling it by adding the following to your homeserver configuration:</p>
<li>When installing from a wheel, sdist, or PyPI, a <code>synctl</code> executable is added
to your Python installation's <code>bin</code>. This should be on your <code>PATH</code>
automatically, though you might need to activate a virtual environment
depending on how you installed Synapse.</li>
</ul>
<h2id="compatibility-dropped-for-mjolnir-131-and-earlier"><aclass="header"href="#compatibility-dropped-for-mjolnir-131-and-earlier">Compatibility dropped for Mjolnir 1.3.1 and earlier</a></h2>
<p>Synapse v1.55.0 drops support for Mjolnir 1.3.1 and earlier.
If you use the Mjolnir module to moderate your homeserver,
please upgrade Mjolnir to version 1.3.2 or later before upgrading Synapse.</p>
<h1id="upgrading-to-v1530"><aclass="header"href="#upgrading-to-v1530">Upgrading to v1.53.0</a></h1>
<h2id="dropping-support-for-webclient-listeners-and-non-https-web_client_location"><aclass="header"href="#dropping-support-for-webclient-listeners-and-non-https-web_client_location">Dropping support for <code>webclient</code> listeners and non-HTTP(S) <code>web_client_location</code></a></h2>
<p>Per the deprecation notice in Synapse v1.51.0, listeners of type <code>webclient</code>
are no longer supported and configuring them is a now a configuration error.</p>
<p>Configuring a non-HTTP(S) <code>web_client_location</code> configuration is is now a
configuration error. Since the <code>webclient</code> listener is no longer supported, this
setting only applies to the root path <code>/</code> of Synapse's web server and no longer
the <code>/_matrix/client/</code> path.</p>
<h2id="stablisation-of-msc3231"><aclass="header"href="#stablisation-of-msc3231">Stablisation of MSC3231</a></h2>
<p>Please update any relevant reverse proxy or firewall configurations appropriately.</p>
<h2id="time-based-cache-expiry-is-now-enabled-by-default"><aclass="header"href="#time-based-cache-expiry-is-now-enabled-by-default">Time-based cache expiry is now enabled by default</a></h2>
<p>Formerly, entries in the cache were not evicted regardless of whether they were accessed after storing.
This behavior has now changed. By default entries in the cache are now evicted after 30m of not being accessed.
To change the default behavior, go to the <code>caches</code> section of the config and change the <code>expire_caches</code> and
<code>cache_entry_ttl</code> flags as necessary. Please note that these flags replace the <code>expiry_time</code> flag in the config.<br/>
The <code>expiry_time</code> flag will still continue to work, but it has been deprecated and will be removed in the future.</p>
<h2id="deprecation-of-capability-orgmatrixmsc3283"><aclass="header"href="#deprecation-of-capability-orgmatrixmsc3283">Deprecation of <code>capability</code><code>org.matrix.msc3283.*</code></a></h2>
<p>The <code>capabilities</code> of MSC3283 from the REST API <code>/_matrix/client/r0/capabilities</code>
<p>are deprecated and scheduled to be removed in Synapse v1.54.0.</p>
<p>The new <code>capabilities</code></p>
<ul>
<li><code>m.set_displayname</code>,</li>
<li><code>m.set_avatar_url</code> and</li>
<li><code>m.3pid_changes</code></li>
</ul>
<p>are now active by default.</p>
<h2id="removal-of-user_may_create_room_with_invites"><aclass="header"href="#removal-of-user_may_create_room_with_invites">Removal of <code>user_may_create_room_with_invites</code></a></h2>
<p>As announced with the release of <ahref="#deprecation-of-the-user_may_create_room_with_invites-module-callback">Synapse 1.47.0</a>,
the deprecated <code>user_may_create_room_with_invites</code> module callback has been removed.</p>
<p>Modules relying on it can instead implement <ahref="https://matrix-org.github.io/synapse/latest/modules/spam_checker_callbacks.html#user_may_invite"><code>user_may_invite</code></a>
and use the <ahref="https://github.com/matrix-org/synapse/blob/872f23b95fa980a61b0866c1475e84491991fa20/synapse/module_api/__init__.py#L869-L876"><code>get_room_state</code></a>
module API to infer whether the invite is happening while creating a room (see <ahref="https://github.com/matrix-org/synapse-domain-rule-checker/blob/e7d092dd9f2a7f844928771dbfd9fd24c2332e48/synapse_domain_rule_checker/__init__.py#L56-L89">this function</a>
as an example). Alternately, modules can also implement <ahref="https://matrix-org.github.io/synapse/latest/modules/third_party_rules_callbacks.html#on_create_room"><code>on_create_room</code></a>.</p>
<h1id="upgrading-to-v1510"><aclass="header"href="#upgrading-to-v1510">Upgrading to v1.51.0</a></h1>
<h2id="deprecation-of-webclient-listeners-and-non-https-web_client_location"><aclass="header"href="#deprecation-of-webclient-listeners-and-non-https-web_client_location">Deprecation of <code>webclient</code> listeners and non-HTTP(S) <code>web_client_location</code></a></h2>
<p>Listeners of type <code>webclient</code> are deprecated and scheduled to be removed in
Synapse v1.53.0.</p>
<p>Similarly, a non-HTTP(S) <code>web_client_location</code> configuration is deprecated and
will become a configuration error in Synapse v1.53.0.</p>
<h1id="upgrading-to-v1500"><aclass="header"href="#upgrading-to-v1500">Upgrading to v1.50.0</a></h1>
<h2id="dropping-support-for-old-python-and-postgres-versions"><aclass="header"href="#dropping-support-for-old-python-and-postgres-versions">Dropping support for old Python and Postgres versions</a></h2>
<p>In line with our <ahref="deprecation_policy.html">deprecation policy</a>,
we've dropped support for Python 3.6 and PostgreSQL 9.6, as they are no
longer supported upstream.</p>
<p>This release of Synapse requires Python 3.7+ and PostgreSQL 10+.</p>
<h1id="upgrading-to-v1470"><aclass="header"href="#upgrading-to-v1470">Upgrading to v1.47.0</a></h1>
<h2id="removal-of-old-room-admin-api"><aclass="header"href="#removal-of-old-room-admin-api">Removal of old Room Admin API</a></h2>
<p>The following admin APIs were deprecated in <ahref="https://github.com/matrix-org/synapse/blob/v1.34.0/CHANGES.md#deprecations-and-removals">Synapse 1.34</a>
(released on 2021-05-17) and have now been removed:</p>
<h2id="deprecation-of-the-user_may_create_room_with_invites-module-callback"><aclass="header"href="#deprecation-of-the-user_may_create_room_with_invites-module-callback">Deprecation of the <code>user_may_create_room_with_invites</code> module callback</a></h2>
<p>The <code>user_may_create_room_with_invites</code> is deprecated and will be removed in a future
version of Synapse. Modules implementing this callback can instead implement
and use the <ahref="https://github.com/matrix-org/synapse/blob/872f23b95fa980a61b0866c1475e84491991fa20/synapse/module_api/__init__.py#L869-L876"><code>get_room_state</code></a>
module API method to infer whether the invite is happening in the context of creating a
room.</p>
<p>We plan to remove this callback in January 2022.</p>
<h1id="upgrading-to-v1450"><aclass="header"href="#upgrading-to-v1450">Upgrading to v1.45.0</a></h1>
<h2id="changes-required-to-media-storage-provider-modules-when-reading-from-the-synapse-configuration-object"><aclass="header"href="#changes-required-to-media-storage-provider-modules-when-reading-from-the-synapse-configuration-object">Changes required to media storage provider modules when reading from the Synapse configuration object</a></h2>
<p>Media storage provider modules that read from the Synapse configuration object (i.e. that
read the value of <code>hs.config.[...]</code>) now need to specify the configuration section they're
reading from. This means that if a module reads the value of e.g. <code>hs.config.media_store_path</code>,
it needs to replace it with <code>hs.config.media.media_store_path</code>.</p>
<h1id="upgrading-to-v1440"><aclass="header"href="#upgrading-to-v1440">Upgrading to v1.44.0</a></h1>
<h2id="the-url-preview-cache-is-no-longer-mirrored-to-storage-providers"><aclass="header"href="#the-url-preview-cache-is-no-longer-mirrored-to-storage-providers">The URL preview cache is no longer mirrored to storage providers</a></h2>
<p>The <code>url_cache/</code> and <code>url_cache_thumbnails/</code> directories in the media store are
no longer mirrored to storage providers. These two directories can be safely
deleted from any configured storage providers to reclaim space.</p>
<h1id="upgrading-to-v1430"><aclass="header"href="#upgrading-to-v1430">Upgrading to v1.43.0</a></h1>
<h2id="the-spaces-summary-apis-can-now-be-handled-by-workers"><aclass="header"href="#the-spaces-summary-apis-can-now-be-handled-by-workers">The spaces summary APIs can now be handled by workers</a></h2>
<h2id="user-interactive-authentication-fallback-templates-can-now-display-errors"><aclass="header"href="#user-interactive-authentication-fallback-templates-can-now-display-errors">User-interactive authentication fallback templates can now display errors</a></h2>
<p>This may affect you if you make use of custom HTML templates for the
<ahref="../synapse/res/templates/recaptcha.html">reCAPTCHA</a> or
<p>The template is now provided an <code>error</code> variable if the authentication
process failed. See the default templates linked above for an example.</p>
<h2id="removal-of-out-of-date-email-pushers"><aclass="header"href="#removal-of-out-of-date-email-pushers">Removal of out-of-date email pushers</a></h2>
<p>Users will stop receiving message updates via email for addresses that were
<h1id="upgrading-to-v1410"><aclass="header"href="#upgrading-to-v1410">Upgrading to v1.41.0</a></h1>
<h2id="add-support-for-routing-outbound-http-requests-via-a-proxy-for-federation"><aclass="header"href="#add-support-for-routing-outbound-http-requests-via-a-proxy-for-federation">Add support for routing outbound HTTP requests via a proxy for federation</a></h2>
<p>Since Synapse 1.6.0 (2019-11-26) you can set a proxy for outbound HTTP requests via
http_proxy/https_proxy environment variables. This proxy was set for:</p>
<ul>
<li>push</li>
<li>url previews</li>
<li>phone-home stats</li>
<li>recaptcha validation</li>
<li>CAS auth validation</li>
<li>OpenID Connect</li>
<li>Federation (checking public key revocation)</li>
</ul>
<p>In this version we have added support for outbound requests for:</p>
<ul>
<li>Outbound federation</li>
<li>Downloading remote media</li>
<li>Fetching public keys of other servers</li>
</ul>
<p>These requests use the same proxy configuration. If you have a proxy configuration we
recommend to verify the configuration. It may be necessary to adjust the <code>no_proxy</code>
environment variable.</p>
<p>See <ahref="setup/forward_proxy.html">using a forward proxy with Synapse documentation</a> for
details.</p>
<h2id="deprecation-of-template_dir"><aclass="header"href="#deprecation-of-template_dir">Deprecation of <code>template_dir</code></a></h2>
<p>The <code>template_dir</code> settings in the <code>sso</code>, <code>account_validity</code> and <code>email</code> sections of the
configuration file are now deprecated. Server admins should use the new
<code>templates.custom_template_directory</code> setting in the configuration file and use one single
custom template directory for all aforementioned features. Template file names remain
unchanged. See <ahref="https://matrix-org.github.io/synapse/latest/templates.html">the related documentation</a>
for more information and examples.</p>
<p>We plan to remove support for these settings in October 2021.</p>
<h2id="_synapseadminv1usersuseridmedia-must-be-handled-by-media-workers"><aclass="header"href="#_synapseadminv1usersuseridmedia-must-be-handled-by-media-workers"><code>/_synapse/admin/v1/users/{userId}/media</code> must be handled by media workers</a></h2>
<h1id="upgrading-to-v1390"><aclass="header"href="#upgrading-to-v1390">Upgrading to v1.39.0</a></h1>
<h2id="deprecation-of-the-current-third-party-rules-module-interface"><aclass="header"href="#deprecation-of-the-current-third-party-rules-module-interface">Deprecation of the current third-party rules module interface</a></h2>
<p>The current third-party rules module interface is deprecated in favour of the new generic
modules system introduced in Synapse v1.37.0. Authors of third-party rules modules can refer
<h1id="upgrading-to-v1380"><aclass="header"href="#upgrading-to-v1380">Upgrading to v1.38.0</a></h1>
<h2id="re-indexing-of-events-table-on-postgres-databases"><aclass="header"href="#re-indexing-of-events-table-on-postgres-databases">Re-indexing of <code>events</code> table on Postgres databases</a></h2>
<p>This release includes a database schema update which requires re-indexing one of
the larger tables in the database, <code>events</code>. This could result in increased
disk I/O for several hours or days after upgrading while the migration
completes. Furthermore, because we have to keep the old indexes until the new
indexes are ready, it could result in a significant, temporary, increase in
disk space.</p>
<p>To get a rough idea of the disk space required, check the current size of one
of the indexes. For example, from a <code>psql</code> shell, run the following sql:</p>
<p>On this server, it would be wise to ensure that at least 1152MB are free.</p>
<p>The additional disk space will be freed once the migration completes.</p>
<p>SQLite databases are unaffected by this change.</p>
<h1id="upgrading-to-v1370"><aclass="header"href="#upgrading-to-v1370">Upgrading to v1.37.0</a></h1>
<h2id="deprecation-of-the-current-spam-checker-interface"><aclass="header"href="#deprecation-of-the-current-spam-checker-interface">Deprecation of the current spam checker interface</a></h2>
<p>The current spam checker interface is deprecated in favour of a new generic modules system.
<p>The <code>room_invite_state_types</code> configuration setting has been deprecated
and replaced with <code>room_prejoin_state</code>. See the <ahref="https://github.com/matrix-org/synapse/blob/v1.34.0/docs/sample_config.yaml#L1515">sample configuration
file</a>.</p>
<p>If you have set <code>room_invite_state_types</code> to the default value you
should simply remove it from your configuration file. The default value
<p>If you have customised this value, you should remove
<code>room_invite_state_types</code> and configure <code>room_prejoin_state</code> instead.</p>
<h1id="upgrading-to-v1330"><aclass="header"href="#upgrading-to-v1330">Upgrading to v1.33.0</a></h1>
<h2id="account-validity-html-templates-can-now-display-a-users-expiration-date"><aclass="header"href="#account-validity-html-templates-can-now-display-a-users-expiration-date">Account Validity HTML templates can now display a user's expiration date</a></h2>
<p>This may affect you if you have enabled the account validity feature,
and have made use of a custom HTML template specified by the
<p>The template can now accept an <code>expiration_ts</code> variable, which
represents the unix timestamp in milliseconds for the future date of
which their account has been renewed until. See the <ahref="https://github.com/matrix-org/synapse/blob/release-v1.33.0/synapse/res/templates/account_renewed.html">default
template</a>
for an example of usage.</p>
<p>ALso note that a new HTML template, <code>account_previously_renewed.html</code>,
has been added. This is is shown to users when they attempt to renew
their account with a valid renewal token that has already been used
before. The default template contents can been found
and can also accept an <code>expiration_ts</code> variable. This template replaces
the error message users would previously see upon attempting to use a
valid renewal token more than once.</p>
<h1id="upgrading-to-v1320"><aclass="header"href="#upgrading-to-v1320">Upgrading to v1.32.0</a></h1>
<h2id="regression-causing-connected-prometheus-instances-to-become-overwhelmed"><aclass="header"href="#regression-causing-connected-prometheus-instances-to-become-overwhelmed">Regression causing connected Prometheus instances to become overwhelmed</a></h2>
<h2id="dropping-support-for-old-python-postgres-and-sqlite-versions"><aclass="header"href="#dropping-support-for-old-python-postgres-and-sqlite-versions">Dropping support for old Python, Postgres and SQLite versions</a></h2>
we've dropped support for Python 3.5 and PostgreSQL 9.5, as they are no
longer supported upstream.</p>
<p>This release of Synapse requires Python 3.6+ and PostgresSQL 9.6+ or
SQLite 3.22+.</p>
<h2id="removal-of-old-list-accounts-admin-api"><aclass="header"href="#removal-of-old-list-accounts-admin-api">Removal of old List Accounts Admin API</a></h2>
<p>The deprecated v1 "list accounts" admin API
(<code>GET /_synapse/admin/v1/users/<user_id></code>) has been removed in this
has been available since Synapse 1.7.0 (2019-12-13), and is accessible
under <code>GET /_synapse/admin/v2/users</code>.</p>
<p>The deprecation of the old endpoint was announced with Synapse 1.28.0
(released on 2021-02-25).</p>
<h2id="application-services-must-use-type-mloginapplication_service-when-registering-users"><aclass="header"href="#application-services-must-use-type-mloginapplication_service-when-registering-users">Application Services must use type <code>m.login.application_service</code> when registering users</a></h2>
<p>In compliance with the <ahref="https://matrix.org/docs/spec/application_service/r0.1.2#server-admin-style-permissions">Application Service
spec</a>,
Application Services are now required to use the
<code>m.login.application_service</code> type when registering users via the
<code>/_matrix/client/r0/register</code> endpoint. This behaviour was deprecated in
Synapse v1.30.0.</p>
<p>Please ensure your Application Services are up to date.</p>
<h1id="upgrading-to-v1290"><aclass="header"href="#upgrading-to-v1290">Upgrading to v1.29.0</a></h1>
<h2id="requirement-for-x-forwarded-proto-header"><aclass="header"href="#requirement-for-x-forwarded-proto-header">Requirement for X-Forwarded-Proto header</a></h2>
<p>When using Synapse with a reverse proxy (in particular, when using the
<h1id="upgrading-to-v1270"><aclass="header"href="#upgrading-to-v1270">Upgrading to v1.27.0</a></h1>
<h2id="changes-to-callback-uri-for-oauth2--openid-connect-and-saml2"><aclass="header"href="#changes-to-callback-uri-for-oauth2--openid-connect-and-saml2">Changes to callback URI for OAuth2 / OpenID Connect and SAML2</a></h2>
<p>This version changes the URI used for callbacks from OAuth2 and SAML2
identity providers:</p>
<ul>
<li>
<p>If your server is configured for single sign-on via an OpenID
Connect or OAuth2 identity provider, you will need to add
<code>[synapse public baseurl]/_synapse/client/oidc/callback</code> to the list
of permitted "redirect URIs" at the identity provider.</p>
<h1id="upgrading-to-v1260"><aclass="header"href="#upgrading-to-v1260">Upgrading to v1.26.0</a></h1>
<h2id="rolling-back-to-v1250-after-a-failed-upgrade"><aclass="header"href="#rolling-back-to-v1250-after-a-failed-upgrade">Rolling back to v1.25.0 after a failed upgrade</a></h2>
<p>v1.26.0 includes a lot of large changes. If something problematic
occurs, you may want to roll-back to a previous version of Synapse.
Because v1.26.0 also includes a new database schema version, reverting
that version is also required alongside the generic rollback
instructions mentioned above. In short, to roll back to v1.25.0 you need
to:</p>
<ol>
<li>
<p>Stop the server</p>
</li>
<li>
<p>Decrease the schema version in the database:</p>
<pre><codeclass="language-sql">UPDATE schema_version SET version = 58;
</code></pre>
</li>
<li>
<p>Delete the ignored users & chain cover data:</p>
<pre><codeclass="language-sql">DROP TABLE IF EXISTS ignored_users;
<p>This release introduces a backwards-incompatible change to modules
making use of <code>ThirdPartyEventRules</code> in Synapse. If you make use of a
module defined under the <code>third_party_event_rules</code> config option, please
make sure it is updated to handle the below change:</p>
<p>The <code>http_client</code> argument is no longer passed to modules as they are
initialised. Instead, modules are expected to make use of the
<code>http_client</code> property on the <code>ModuleApi</code> class. Modules are now passed
a <code>module_api</code> argument during initialisation, which is an instance of
<code>ModuleApi</code>. <code>ModuleApi</code> instances have a <code>http_client</code> property which
acts the same as the <code>http_client</code> argument previously passed to
<code>ThirdPartyEventRules</code> modules.</p>
<h1id="upgrading-to-v1210"><aclass="header"href="#upgrading-to-v1210">Upgrading to v1.21.0</a></h1>
<h2id="forwarding-_synapseclient-through-your-reverse-proxy"><aclass="header"href="#forwarding-_synapseclient-through-your-reverse-proxy">Forwarding <code>/_synapse/client</code> through your reverse proxy</a></h2>
<code>/_synapse/client/password_reset/{medium}/submit_token</code> with the query
parameters from the original link, presented as a URL-encoded form. See
the file itself for more details.</p>
<h2id="updated-single-sign-on-html-templates"><aclass="header"href="#updated-single-sign-on-html-templates">Updated Single Sign-on HTML Templates</a></h2>
<p>The <code>saml_error.html</code> template was removed from Synapse and replaced
with the <code>sso_error.html</code> template. If your Synapse is configured to use
SAML and a custom <code>sso_redirect_confirm_template_dir</code> configuration then
any customisations of the <code>saml_error.html</code> template will need to be
merged into the <code>sso_error.html</code> template. These templates are similar,
but the parameters are slightly different:</p>
<ul>
<li>The <code>msg</code> parameter should be renamed to <code>error_description</code>.</li>
<li>There is no longer a <code>code</code> parameter for the response code.</li>
<li>A string <code>error</code> parameter is available that includes a short hint
of why a user is seeing the error page.</li>
</ul>
<h1id="upgrading-to-v1180"><aclass="header"href="#upgrading-to-v1180">Upgrading to v1.18.0</a></h1>
<h2id="docker--py3-suffix-will-be-removed-in-future-versions"><aclass="header"href="#docker--py3-suffix-will-be-removed-in-future-versions">Docker <code>-py3</code> suffix will be removed in future versions</a></h2>
<h2id="redis-replication-is-now-recommended-in-lieu-of-tcp-replication"><aclass="header"href="#redis-replication-is-now-recommended-in-lieu-of-tcp-replication">Redis replication is now recommended in lieu of TCP replication</a></h2>
<p>When setting up worker processes, we now recommend the use of a Redis
server for replication. <strong>The old direct TCP connection method is
deprecated and will be removed in a future release.</strong> See
<h1id="upgrading-to-v1140"><aclass="header"href="#upgrading-to-v1140">Upgrading to v1.14.0</a></h1>
<p>This version includes a database update which is run as part of the
upgrade, and which may take a couple of minutes in the case of a large
server. Synapse will not respond to HTTP requests while this update is
taking place.</p>
<h1id="upgrading-to-v1130"><aclass="header"href="#upgrading-to-v1130">Upgrading to v1.13.0</a></h1>
<h2id="incorrect-database-migration-in-old-synapse-versions"><aclass="header"href="#incorrect-database-migration-in-old-synapse-versions">Incorrect database migration in old synapse versions</a></h2>
<p>A bug was introduced in Synapse 1.4.0 which could cause the room
directory to be incomplete or empty if Synapse was upgraded directly
from v1.2.1 or earlier, to versions between v1.4.0 and v1.12.x.</p>
<p>This will <em>not</em> be a problem for Synapse installations which were:</p>
<p>: - created at v1.4.0 or later,
- upgraded via v1.3.x, or
- upgraded straight from v1.2.1 or earlier to v1.13.0 or later.</p>
<p>If completeness of the room directory is a concern, installations which
<p>Plugins using the <code>complete_sso_login</code> method of
<code>synapse.module_api.ModuleApi</code> should update to using the async/await
version <code>complete_sso_login_async</code> which includes additional checks. The
non-async version is considered deprecated.</p>
<h2id="rolling-back-to-v1124-after-a-failed-upgrade"><aclass="header"href="#rolling-back-to-v1124-after-a-failed-upgrade">Rolling back to v1.12.4 after a failed upgrade</a></h2>
<p>v1.13.0 includes a lot of large changes. If something problematic
occurs, you may want to roll-back to a previous version of Synapse.
Because v1.13.0 also includes a new database schema version, reverting
that version is also required alongside the generic rollback
instructions mentioned above. In short, to roll back to v1.12.4 you need
to:</p>
<ol>
<li>
<p>Stop the server</p>
</li>
<li>
<p>Decrease the schema version in the database:</p>
<pre><codeclass="language-sql">UPDATE schema_version SET version = 57;
</code></pre>
</li>
<li>
<p>Downgrade Synapse by following the instructions for your
installation method in the "Rolling back to older versions"
section above.</p>
</li>
</ol>
<h1id="upgrading-to-v1120"><aclass="header"href="#upgrading-to-v1120">Upgrading to v1.12.0</a></h1>
<p>This version includes a database update which is run as part of the
upgrade, and which may take some time (several hours in the case of a
large server). Synapse will not respond to HTTP requests while this
update is taking place.</p>
<p>This is only likely to be a problem in the case of a server which is
participating in many rooms.</p>
<olstart="0">
<li>
<p>As with all upgrades, it is recommended that you have a recent
backup of your database which can be used for recovery in the event
of any problems.</p>
</li>
<li>
<p>As an initial check to see if you will be affected, you can try
<h4id="delegate-email-to-an-identity-server"><aclass="header"href="#delegate-email-to-an-identity-server">Delegate email to an identity server</a></h4>
<p>Some admins will wish to continue using email verification as part of
the registration process, but will not immediately have an appropriate
SMTP server at hand.</p>
<p>To this end, we will continue to support email verification delegation
via the <code>vector.im</code> and <code>matrix.org</code> identity servers for two months.
Support for delegated email verification will be disabled on Monday 2nd
December.</p>
<p>The <code>account_threepid_delegates</code> dictionary defines whether the
homeserver should delegate an external server (typically an <ahref="https://matrix.org/docs/spec/identity_service/r0.2.1">identity
server</a>) to handle
sending confirmation messages via email and SMS.</p>
<p>So to delegate email verification, in <code>homeserver.yaml</code>, set
<code>account_threepid_delegates.email</code> to the base URL of an identity
