This was only used for upgrading from Zulip < 1.9.0, which is no
longer possible because Zulip < 2.1.0 had no common supported
platforms with current main.
If we ever want this optimization for a future migration, it would be
better implemented using Django merge migrations.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This is required in order to lock down the RabbitMQ port to only
listen on localhost. If the nodename is `rabbit@hostname`, in most
circumstances the hostname will resolve to an external IP, which the
rabbitmq port will not be bound to.
Installs which used `rabbit@hostname`, due to RabbitMQ having been
installed before Zulip, would not have functioned if the host or
RabbitMQ service was restarted, as the localhost restrictions in the
RabbitMQ configuration would have made rabbitmqctl (and Zulip cron
jobs that call it) unable to find the rabbitmq server.
The previous commit ensures that configure-rabbitmq is re-run after
the nodename has changed. However, rabbitmq needs to be stopped
before `rabbitmq-env.conf` is changed; we use an `onlyif` on an `exec`
to print the warning about the node change, and let the subsequent
config change and notify of the service and configure-rabbitmq to
complete the re-configuration.
The Erlang `epmd` daemon listens on port 4369, and provides
information (without authentication) about which Erlang processes are
listening on what ports. This information is not itself a
vulnerability, but may provide information for remote attackers about
what local Erlang services (such as `rabbitmq-server`) are running,
and where.
`epmd` supports an `ERL_EPMD_ADDRESS` environment variable to limit
which interfaces it binds on. While this environment variable is set
in `/etc/default/rabbitmq-server`, Zulip unfortunately attempts to
start `epmd` using an explicit `exec` block, which ignores those
settings.
Regardless, this lack of `ERL_EPMD_ADDRESS` variable only controls
`epmd`'s startup upon first installation. Upon reboot, there are two
ways in which `epmd` might be started, neither of which respect
`ERL_EPMD_ADDRESS`:
- On Focal, an `epmd` service exists and is activated, which uses
systemd's configuration to choose which interfaces to bind on, and
thus `ERL_EPMD_ADDRESS` is irrelevant.
- On Bionic (and Focal, due to a broken dependency from
`rabbitmq-server` to `epmd@` instead of `epmd`, which may lead to
the explicit `epmd` service losing a race), `epmd` is started by
`rabbitmq-server` when it does not detect a running instance.
Unfortunately, only `/etc/init.d/rabbitmq-server` would respects
`/etc/default/rabbitmq-server` -- and it defers the actual startup
to using systemd, which does not pass the environment variable
down. Thus, `ERL_EPMD_ADDRESS` is also irrelevant here.
We unfortunately cannot limit `epmd` to only listening on localhost,
due to a number of overlapping bugs and limitations:
- Manually starting `epmd` with `-address 127.0.0.1` silently fails
to start on hosts with IPv6 disabled, due to an Erlang bug ([1],
[2]).
- The dependencies of the systemd `rabbitmq-server` service can be
fixed to include the `epmd` service, and systemd can be made to
bind to `127.0.0.1:4369` and pass that socket to `epmd`, bypassing
the above bug. However, the startup of this service is not
guaranteed, because it races with other sources of `epmd` (see
below).
- Any process that runs `rabbitmqctl` results in `epmd` being started
if one is not currently running; these instances do not respect any
environment variables as to which addresses to bind on. This is
also triggered by `service rabbitmq-server status`, as well as
various Zulip cron jobs which inspect the rabbitmq queues. As
such, it is difficult-to-impossible to ensure that some other
`epmd` process will not win the race and open the port on all
interfaces.
Since the only known exposure from leaving port 4369 open is
information that rabbitmq is running on the host, and the complexity
of adjusting this to only bind on localhost is high, we remove the
setting which does not address the problem, and document that the port
is left open, and should be protected via system-level or
network-level firewalls.
[1]: https://bugs.launchpad.net/ubuntu/+source/erlang/+bug/1374109
[2]: https://github.com/erlang/otp/issues/4820
As a consequence:
• Bump minimum supported Python version to 3.7.
• Move Vagrant environment to Debian 10, which has Python 3.7.
• Move CI frontend tests to Debian 10.
• Move production build test to Debian 10.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
With tweaks to security-model.md by tabbott to expand the SSO acronym.
Ignored, but still needs discussion on whether we should exclude this
rule:
```
The word ‘install’ is not a noun.
✗ ...ble to connect to the client during the install process: So you'll need to shut down a...
^^^^^^^
✓ ...ble to connect to the client during the installation process: So you'll need to shut down a...
A_INSTALL: a/the + install
The word ‘install’ is not a noun.
✗ ...detected at install time will cause the install to abort. If you already have PostgreSQ...
^^^^^^^
✓ ...detected at install time will cause the installation to abort. If you already have PostgreSQ...
A_INSTALL: a/the + install
```
Because Camo includes logic to deny access to private subnets, routing
its requests through Smokescreen is generally not necessary. However,
it may be necessary if Zulip has configured a non-Smokescreen exit
proxy.
Default Camo to using the proxy only if it is not Smokescreen, with a
new `proxy.enable_for_camo` setting to override this behaviour if need
be. Note that that setting is in `zulip.conf` on the host with Camo
installed -- not the Zulip frontend host, if they are different.
Fixes: #20550.
For `no_serve_uploads`, `http_only`, which previously specified
"non-empty" to enable, this tightens what values are true. For
`pgroonga` and `queue_workers_multiprocess`, this broadens the
possible values from `enabled`, and `true` respectively.
Restarting the uwsgi processes by way of supervisor opens a window
during which nginx 502's all responses. uwsgi has a configuration
called "chain reloading" which allows for rolling restart of the uwsgi
processes, such that only one process at once in unavailable; see
uwsgi documentation ([1]).
The tradeoff is that this requires that the uwsgi processes load the
libraries after forking, rather than before ("lazy apps"); in theory
this can lead to larger memory footprints, since they are not shared.
In practice, as Django defers much of the loading, this is not as much
of an issue. In a very basic test of memory consumption (measured by
total memory - free - caches - buffers; 6 uwsgi workers), both
immediately after restarting Django, and after requesting `/` 60 times
with 6 concurrent requests:
| Non-lazy | Lazy app | Difference
------------------+------------+------------+-------------
Fresh | 2,827,216 | 2,870,480 | +43,264
After 60 requests | 3,332,284 | 3,409,608 | +77,324
..................|............|............|.............
Difference | +505,068 | +539,128 | +34,060
That is, "lazy app" loading increased the footprint pre-requests by
43MB, and after 60 requests grew the memory footprint by 539MB, as
opposed to non-lazy loading, which grew it by 505MB. Using wsgi "lazy
app" loading does increase the memory footprint, but not by a large
percentage.
The other effect is that processes may be served by either old or new
code during the restart window. This may cause transient failures
when new frontend code talks to old backend code.
Enable chain-reloading during graceful, puppetless restarts, but only
if enabled via a zulip.conf configuration flag.
Fixes#2559.
[1]: https://uwsgi-docs.readthedocs.io/en/latest/articles/TheArtOfGracefulReloading.html#chain-reloading-lazy-apps
This replaces the TERMS_OF_SERVICE and PRIVACY_POLICY settings with
just a POLICIES_DIRECTORY setting, in order to support settings (like
Zulip Cloud) where there's more policies than just those two.
With minor changes by Eeshan Garg.
The certbot package installs its own systemd timer (and cron job,
which disabled itself if systemd is enabled) which updates
certificates. This process races with the cron job which Zulip
installs -- the only difference being that Zulip respects the
`certbot.auto_renew` setting, and that it passes the deploy hook.
This means that occasionally nginx would not be reloaded, when the
systemd timer caught the expiration first.
Remove the custom cron job and `certbot-maybe-renew` script, and
reconfigure certbot to always reload nginx after deploying, using
certbot directory hooks.
Since `certbot.auto_renew` can't have an effect, remove the setting.
In turn, this removes the need for `--no-zulip-conf` to
`setup-certbot`. `--deploy-hook` is similarly removed, as running
deploy hooks to restart nginx is now the default; pass
`--no-directory-hooks` in standalone mode to not attempt to reload
nginx. The other property of `--deploy-hook`, of skipping symlinking
into place, is given its own flog.
We recently changed /developer-community to /development-community.
Now that this change is in production, we can also migrate the
external links in our ReadTheDocs documentation.
PostgreSQL 11 and below used a configuration file names
`recovery.conf` to manage replicas and standbys; support for this was
removed in PostgreSQL 12[1], and the configuration parameters were
moved into the main `postgresql.conf`.
Add `zulip.conf` settings for the primary server hostname and
replication username, so that the complete `postgresql.conf`
configuration on PostgreSQL 14 can continue to be managed, even when
replication is enabled. For consistency, also begin writing out the
`recovery.conf` for PostgreSQL 11 and below.
In PostgreSQL 12 configuration and later, the `wal_level =
hot_standby` setting is removed, as `hot_standby` is equivalent to
`replica`, which is the default value[2]. Similarly, the
`hot_standby = on` setting is also the default[3].
Documentation is added for these features, and the commentary on the
"Export and Import" page referencing files under `puppet/zulip_ops/`
is removed, as those files no longer have any replication-specific
configuration.
[1]: https://www.postgresql.org/docs/current/recovery-config.html
[2]: https://www.postgresql.org/docs/12/runtime-config-wal.html#GUC-WAL-LEVEL
[3]: https://www.postgresql.org/docs/12/runtime-config-replication.html#GUC-HOT-STANDBY
When Zulip is run behind one or more reverse proxies, you must
configure `loadbalancer.ips` so that Zulip respects the client IP
addresses found in the `X-Forwarded-For` header. This is not
immediately clear from the documentation, so this commit makes it more
clear and augments the existing examples to showcase this need.
Fixes: #19073
OIDC config features a get_secret call (so it requires adding an import)
as well as having a bunch of its instructions in the form of comments on
the various keys of the config dict - thus users should really update
settings.py to fetch all of that.
The upstream of the `camo` repository[1] has been unmaintained for
several years, and is now archived by the owner. Additionally, it has
a number of limitations:
- It is installed as a sysinit service, which does not run under
Docker
- It does not prevent access to internal IPs, like 127.0.0.1
- It does not respect standard `HTTP_proxy` environment variables,
making it unable to use Smokescreen to prevent the prior flaw
- It occasionally just crashes, and thus must have a cron job to
restart it.
Swap camo out for the drop-in replacement go-camo[2], which has the
same external API, requiring not changes to Django code, but is more
maintained. Additionally, it resolves all of the above complaints.
go-camo is not configured to use Smokescreen as a proxy, because its
own private-IP filtering prevents using a proxy which lies within that
IP space. It is also unclear if the addition of Smokescreen would
provide any additional protection over the existing IP address
restrictions in go-camo.
go-camo has a subset of the security headers that our nginx reverse
proxy sets, and which camo set; provide the missing headers with `-H`
to ensure that go-camo, if exposed from behind some other non-nginx
load-balancer, still provides the necessary security headers.
Fixes#18351 by moving to supervisor.
Fixeszulip/docker-zulip#298 also by moving to supervisor.
[1] https://github.com/atmos/camo
[2] https://github.com/cactus/go-camo
This is an additional security hardening step, to make Zulip default
to preventing SSRF attacks. The overhead of running Smokescreen is
minimal, and there is no reason to force deployments to take
additional steps in order to secure themselves against SSRF attacks.
Deployments which already have a different external proxy configured
will not gain a local Smokescreen installation, and running without
Smokescreen is supported by explicitly unsetting the `host` or `port`
values in `/etc/zulip/zulip.conf`.
This helps increase the probability that folks read the guidelines for how the
chat.zulip.org community works and what streams to use before arriving there.
Fixes#19827.
Previously, our docs had links to various versions of the Django docs,
eg https://docs.djangoproject.com/en/1.10/topics/migrations/ and
https://docs.djangoproject.com/en/2.0/ref/signals/#post-save, opening
a link to a doc with an outdated Django version would show a warning
"This document is for an insecure version of Django that is no longer
supported. Please upgrade to a newer release!".
This commit uses a search with the regex
"docs.djangoproject.com/en/([0-9].[0-9]*)/" and replaces all matches
inside the /docs/ folder with "docs.djangoproject.com/en/3.2/".
All the new links in this commit have been generated by the above
replace and each link has then been manually checked to ensure that
(1) the page still exists and has not been moved to a new location
(and it has been found that no page has been moved like this), (2)
that the anchor that we're linking to has not been changed (and it has
been found that this happened once, for https://docs.djangoproject.com
/en/1.8/ref/django-admin/#runserver-port-or-address-port, where
/#runserver-port-or-address-port was changed to /#runserver).
The links we have now redirect to "My groups" and not to our
Google group. Also, the RSS feed is no longer supported by Google,
so we should no longer link to it.
Fixes#19560.
It's better to explicitly list the possibilities. Also, the
recommendation regarding is_active should be changed to a strict
"Don't", as Subscription.is_user_active is a denormalized field and
flipping a user's is_active will cause inconsistent state by leaving
Subscriptions unupdated. Given that similar things can be introduced in
the future for any other flag not officially supported by having a
setter, the recommendation should "Don't" in general.
It feels like the "Same as" content was unnecessarily requiring the
user to bounce around in these cases.
(I've left the "Same as" text for the Ubuntu ones, where it's two
steps in a row to follow).
Fixes#17456.
The main tricky part has to do with what values the attribute should
have. LDAP defines a Boolean as
Boolean = "TRUE" / "FALSE"
so ideally we'd always see exactly those values. However,
although the issue is now marked as resolved, the discussion in
https://pagure.io/freeipa/issue/1259 shows how this may not always be
respected - meaning it makes sense for us to be more liberal in
interpreting these values.
The support for bullseye was added in #17951
but it was not documented as bullseye was
frozen and did not have proper configuration
files, hence wasn't documented.
Since now bullseye is released as a stable
version, it's support can be documented.
We previously used `zulip-puppet-apply` with a custom config file,
with an updated PostgreSQL version but more limited set of
`puppet_classes`, to pre-create the basic settings for the new cluster
before running `pg_upgradecluster`.
Unfortunately, the supervisor config uses `purge => true` to remove
all SUPERVISOR configuration files that are not included in the puppet
configuration; this leads to it removing all other supervisor
processes during the upgrade, only to add them back and start them
during the second `zulip-puppet-apply`.
It also leads to `process-fts-updates` not being started after the
upgrade completes; this is the one supervisor config file which was
not removed and re-added, and thus the one that is not re-started due
to having been re-added. This was not detected in CI because CI added
a `start-server` command which was not in the upgrade documentation.
Set a custom facter fact that prevents the `purge` behaviour of the
supervisor configuration. We want to preserve that behaviour in
general, and using `zulip-puppet-apply` continues to be the best way
to pre-set-up the PostgreSQL configuration -- but we wish to avoid
that behaviour when we know we are applying a subset of the puppet
classes.
Since supervisor configs are no longer removed and re-added, this
requires an explicit start-server step in the instructions after the
upgrades complete. This brings the documentation into alignment with
what CI is testing.
Recommonmark is no longer maintained, and MyST-Parser is much more
complete.
https://myst-parser.readthedocs.io/
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Commit 30eaed0378 (#15001) incorrectly
inserted a different section between the anchor and the heading.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
The auth attempt rate limit is quite low (on purpose), so this can be a
common scenario where a user asks their admin to reset the limit instead
of waiting. We should provide a tool for administrators to handle such
requests without fiddling around with code in manage.py shell.
These checks suffer from a couple notable problems:
- They are only enabled on staging hosts -- where they should never
be run. Since ef6d0ec5ca, these supervisor processes are only
run on one host, and never on the staging host.
- They run as the `nagios` user, which does not have appropriate
permissions, and thus the checks always fail. Specifically,
`nagios` does not have permissions to run `supervisorctl`, since
the socket is owned by the `zulip` user, and mode 0700; and the
`nagios` user does not have permission to access Zulip secrets to
run `./manage.py print_email_delivery_backlog`.
Rather than rewrite these checks to run on a cron as zulip, and check
those file contents as the nagios user, drop these checks -- they can
be rewritten at a later point, or replaced with Prometheus alerting,
and currently serve only to cause always-failing Nagios checks, which
normalizes alert failures.
Leave the files installed if they currently exist, rather than
cluttering puppet with `ensure => absent`; they do no harm if they are
left installed.
Strictly speaking, this sentence is talking about the IdP configuration,
while the backend is just GenericOpenIdConnectBackend, so the new
phrasing is more correct.
The script is added to upgrade steps for 20.04 and Buster because
those are the upgrades that cross glibc 2.28, which is most
problematic. It will also be called out in the upgrade notes, to
catch those that have already done that upgrade.
Fixes#17277.
The main limitation of this implementation is that the sync happens if
the user authing already exists. This means that a new user going
through the sign up flow will not have their custom fields synced upon
finishing it. The fields will get synced on their consecutive log in via
SAML in the future. This can be addressed in the future by moving the
syncing code further down the codepaths to login_or_register_remote_user
and plumbing the data through to the user creation process.
We detail that limitation in the documentation.
Updated the install documentation to include the explanation of the
two new install options `--postgresql-database-name` and
`--postgresql-database-user`.
* Move the extended documentation of code blocks to a separate page.
* Merge "code playgrounds" documentation to be a section of that page.
* Document copy widget on code blocks.
* This commit changes how we refer to "```python" type syntax for code
blocks. Instead of being called a syntax highlighting label, this is
now referred to as a "language tag", since it serves both syntax
highlighting and playgrounds.
* Remap all the links.
* Advertise this new page in various places that previously did not have a link.
Requesting external images is a privacy risk, so route all external
images through Camo.
Tweaked by tabbott for better test coverage, more comments, and to fix
bugs.
This allows access to be more configurable than just setting one
attribute. This can be configured by setting the setting
AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL.
This hits the unauthenticated Github API to get the list of tags,
which is rate-limited to 60 requests per hour. This means that the
tool can only be run 60 times per hour before it starts to exit with
errors, but that seems like a reasonable limit for the moment.
Update `docs/production/install.md` and
`docs/production/deployment.md` to document the install flags that can
be used as part of the installer more clearly.
Fixes#18122.
Using `supervisorctl stop all` to stop the server is not terribly
discoverable, and may stop services which are not part of Zulip
proper.
Add an explicit tool which only stops the relevant services. It also
more carefully controls the order in which services are stopped to
minimize lost requests, and maximally quiesce the server.
Locations which may be stopping _older_ versions of Zulip (without
this script) are left with using `supervisorctl stop all`.
Fixes#14959.
We use GIPHY web SDK to create popover containing GIFs in a
grid format. Simply clicking on the GIFs will insert the GIF in the compose
box.
We add GIPHY logo to compose box action icons which opens the GIPHY
picker popover containing GIFs with "Powered by GIPHY"
attribution.
This adds an option for restricting a ldap user
to only be allowed to login into certain realms.
This is done by configuring an attribute mapping of "org_membership"
to an ldap attribute that will contain the list of subdomains the ldap
user is allowed to access. This is analogous to how it's done in SAML.
Co-authored-by: Mateusz Mandera <mateusz.mandera@zulip.com>
This is more broadly useful than for just Kandra; provide
documentation and means to install Smokescreen for stand-alone
servers, and motivate its use somewhat more.
This document is mainly an answer to a set of questions other
developers have been asking about Zulip's architecture and scalability
design. It's intended for developers working on Zulip, to help with
thinking about where to prioritize further efforts to optimize
scalability.
As of Feb 15th 2019, Hipchat Cloud and Stride
have reached End Of Life and are no longer
supported by Atlassian. Since it is almost 2 years
now we can remove the migration guides.
Boto3 does not allow setting the endpoint url from
the config file. Thus we create a django setting
variable (`S3_ENDPOINT_URL`) which is passed to
service clients and resources of `boto3.Session`.
We also update the uploads-backend documentation
and remove the config environment variable as now
AWS supports the SIGv4 signature format by default.
And the region name is passed as a parameter instead
of creating a config file for just this value.
Fixes#16246.
These are respected by `urllib`, and thus also `requests`. We set
`HTTP_proxy`, not `HTTP_PROXY`, because the latter is ignored in
situations which might be running under CGI -- in such cases it may be
coming from the `Proxy:` header in the request.
This provides a single reference point for all zulip.conf settings;
these mostly link out to the more complete documentation about each
setting, elsewhere.
Fixes#12490.
There is only one PostgreSQL database; the "appdb" is irrelevant.
Also use "postgresql," as it is the name of the software, whereas
"postgres" the name of the binary and colloquial name. This is minor
cleanup, but enabled by the other renames in the previous commit.
The "voyager" name is non-intuitive and not significant.
`zulip::voyager` and `zulip::dockervoyager` stubs are kept for
back-compatibility with existing `zulip.conf` files.
This moves the puppet configuration closer to the "roles and profiles
method"[1] which is suggested for organizing puppet classes. Notably,
here it makes clear which classes are meant to be able to stand alone
as deployments.
Shims are left behind at the previous names, for compatibility with
existing `zulip.conf` files when upgrading.
[1] https://puppet.com/docs/pe/2019.8/the_roles_and_profiles_method
We replace knight command with change_user_role command which
allows us to change role of a user to owner, admins, member and
guest. We can also give/revoke api_super_user permission using
this command.
Tweaked by tabbott to improve the logging output and update documentation.
Fixes#16586.
Restarting servers is what can cause service interruptions, and
increase risk. Add all of the servers that we use to the list of
ignored packages, and uncomment the default allowed-origins in order
to enable unattended upgrades.
There was likely more dependency complexity prior to 97766102df, but
there is now no reason to require that consumers explicitly include
zulip::apt_repository.
`zproject/settings.py` itself is mostly-empty now. Adjust the
references which should now point to `zproject/computed_settings.py`
or `zproject/default_settings.py`.
The OS upgrade paths which go through 2.1 do not call
`upgrade-zulip-stage-2` with `--audit-fts-indexes` because that flag
was added in 3.0.
Add an explicit step to do this audit after the 3.0 upgrade. Stating
it as another command to run, rather than attempting to tell them
to add it to the `upgrade-zulip` call that we're linking to seems
easiest, since that does not dictate if they should upgrade to a
release or from the tip of git.
We do not include a step describing this for the Trusty -> Xenial
upgrade, because the last step already chains into Xenial -> Bionic,
which itself describes auditing the indexes.
Fixes#15877.
Only Zulip 3.0 and above support the `--audit-fts-indexes` option to
`upgrade-zulip-stage-2`; saying "same as Bionic to Focal" on other
other steps, which are for Zulip 2.1 or 2.0, will result in errors.
Provide the full text of the updated `upgrade-zulip-stage-2` call in
step 5 for all non-3.0 upgrades. For Trusty to Xenial and Stretch to
Buster, we do not say "Same as Xenial to Bionic" , because it is
likely that readers do not notice that step does not read "Same as
Bionic to Focal."
The apple developer webapp consistently refers this App ID. So,
this clears any confusion that can occur.
Since python social auth only requires us to include App ID in
_AUDIENCE(a list), we do that in computed settings making it easier for
server admin and we make it much clear by having it set to
APP_ID instead of BUNDLE_ID.
wal-g was used in `puppet/zulip` by env-wal-g, but only installed in
`puppet/zulip_ops`.
Merge all of the dependencies of doing backups using wal-g (wal-g
installation, the pg_backup_and_purge job, the nagios plugin that
verifies it happens) into a common base class in `puppet/zulip`, since
it is generally useful.
Running `pg-upgradecluster` runs the `CREATE TEXT SEARCH DICTIONARY`
and `CREATE TEXT SEARCH CONFIGURATION` from
`zerver/migrations/0001_initial.py` on the new PostgreSQL cluster;
this requires that the stopwords file and dictionary exist _prior_
to `pg_upgradecluster` being run.
This causes a minor dependency conflict -- we do not wish to duplicate
the functionality from `zulip::postgres_appdb_base` which configures
those files, but installing all of `zulip::postgres_appdb_tuned` will
attempt to restart PostgreSQL -- which has not configured the cluster
for the new version yet.
In order to split out configuration of the prerequisites for the
application database, and the steps required to run it, we need to be
able to apply only part of the puppet configuration. Use the
newly-added `--config` argument to provide a more limited `zulip.conf`
which only applies `zulip::postgres_appdb_base` to the new version of
Postgres, creating the required tsearch data files.
This also preserves the property that a failure at any point prior to
the `pg_upgradecluster` is easily recoverable, by re-running
`zulip-puppet-apply`.
Added -d Flag in do-release-upgrade for Bionic to Focal upgrade.
The -d switch is necessary to upgrade from Ubuntu 18.04 LTS
as upgrades have not yet been enabled and will only be enabled
after the first point release of 20.04 LTS.
Source https://wiki.ubuntu.com/FocalFossa/ReleaseNotes
As alluded to in the previous commit, only 3.0 can use the new tooling
-- indeed, it requires it, as the zulip.conf entry must be changed.
Clarify that in the upgrade steps for earlier distributions.
Update the upgrade documentation for the tool added in the previous
step. Only the Bionic -> Focal upgrade step need be updated, because
none of the other upgrade steps can be run starting from a Zulip 3.0
installation.
Fixes#15415.