diff --git a/sysadm/mirror-operations/docker.rst b/sysadm/mirror-operations/docker.rst
index 2c3f7c4..e40469e 100644
--- a/sysadm/mirror-operations/docker.rst
+++ b/sysadm/mirror-operations/docker.rst
@@ -1,472 +1,479 @@
.. _mirror_docker:
Deploy a Software Heritage stack with docker deploy
===================================================
+.. admonition:: Intended audience
+ :class: important
+
+ mirror operators
+
Prerequisities
--------------
According you have a properly set up docker swarm cluster with support for the
`docker stack deploy
`_ command,
e.g.:
.. code-block:: bash
~/swh-docker$ docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
py47518uzdb94y2sb5yjurj22 host2 Ready Active 18.09.7
n9mfw08gys0dmvg5j2bb4j2m7 * host1 Ready Active Leader 18.09.7
Note: on some systems (centos for example), making docker swarm works require
some permission tuning regarding the firewall and selinux.
In the following how-to, we will assume that the service `STACK` name is `swh`
(this name is the last argument of the `docker stack deploy` command below).
Several preparation steps will depend on this name.
-We also use [docker-compose](https://github.com/docker/compose) to merge
-compose files, so make sure it iavailable on your system.
+We also use `docker-compose `_ to merge compose
+files, so make sure it iavailable on your system.
You also need to clone the git repository:
https://forge.softwareheritage.org/source/swh-docker
Set up volumes
--------------
Before starting the `swh` service, you may want to specify where the data
should be stored on your docker hosts.
By default docker will use docker volumes for storing databases and the content of
the objstorage (thus put them in `/var/lib/docker/volumes`).
**Optional:** if you want to specify a different location to put a storage in,
create the storage before starting the docker service. For example for the
`objstorage` service you will need a storage named `_objstorage`:
.. code-block:: bash
~/swh-docker$ docker volume create -d local \
--opt type=none \
--opt o=bind \
--opt device=/data/docker/swh-objstorage \
swh_objstorage
If you want to deploy services like the `swh-objstorage` on several hosts, you
will need a shared storage area in which blob objects will be stored. Typically
a NFS storage can be used for this, or any existing docker volume driver like
-[REX_Rey](https://rexray.readthedocs.io/). This is not covered in this doc.
+`REX-Ray `_. This is not covered in this doc.
Please read the documentation of docker volumes to learn how to use such a
device/driver as volume provider for docker.
Note that the provided `base-services.yaml` file have a few placement
constraints: containers that depends on a volume (db-storage and objstorage)
are stick to the manager node of the cluster, under the assumption persistent
volumes have been created on this node. Make sure this fits your needs, or
amend these placement constraints.
Managing secrets
----------------
Shared passwords (between services) are managed via `docker secret`. Before
being able to start services, you need to define these secrets.
Namely, you need to create a `secret` for:
- `postgres-password`
For example:
.. code-block:: bash
~/swh-docker$ echo 'strong password' | docker secret create postgres-password -
[...]
Creating the swh base services
------------------------------
If you haven't done it yet, clone this git repository:
.. code-block:: bash
~$ git clone https://forge.softwareheritage.org/source/swh-docker.git
~$ cd swh-docker
then from within this repository, just type:
.. code-block:: bash
~/swh-docker$ docker stack deploy -c base-services.yml swh
Creating network swh-mirror_default
Creating config swh-mirror_storage
Creating config swh-mirror_objstorage
Creating config swh-mirror_nginx
Creating config swh-mirror_web
Creating service swh-mirror_grafana
Creating service swh-mirror_prometheus-statsd-exporter
Creating service swh-mirror_web
Creating service swh-mirror_objstorage
Creating service swh-mirror_db-storage
Creating service swh-mirror_memcache
Creating service swh-mirror_storage
Creating service swh-mirror_nginx
Creating service swh-mirror_prometheus
~/swh-docker$ docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
sz98tofpeb3j swh-mirror_db-storage global 1/1 postgres:11
sp36lbgfd4qi swh-mirror_grafana replicated 1/1 grafana/grafana:latest
7oja81jngiwo swh-mirror_memcache replicated 1/1 memcached:latest
y5te0gqs93li swh-mirror_nginx replicated 1/1 nginx:latest *:5081->5081/tcp
79t3r3mv3qn6 swh-mirror_objstorage replicated 1/1 softwareheritage/base:20200918-133743
l7q2zocoyvq6 swh-mirror_prometheus global 1/1 prom/prometheus:latest
p6hnd90qnr79 swh-mirror_prometheus-statsd-exporter replicated 1/1 prom/statsd-exporter:latest
jjry62tz3k76 swh-mirror_storage replicated 1/1 softwareheritage/base:20200918-133743
jkkm7qm3awfh swh-mirror_web replicated 1/1 softwareheritage/web:20200918-133743
This will start a series of containers with:
- an objstorage service,
- a storage service using a postgresql database as backend,
- a web app front end,
- a memcache for the web app,
- a prometheus monitoring app,
- a prometeus-statsd exporter,
- a grafana server,
- an nginx server serving as reverse proxy for grafana and swh-web.
using the latest published version of the docker images by default.
The nginx frontend will listen on the 5081 port, so you can use:
- http://localhost:5081/ to navigate your local copy of the archive,
- http://localhost:5081/grafana/ to explore the monitoring probes
(log in with admin/admin).
+.. warning::
->[!WARNING]
->the 'latest' docker images work, it is highly recommended to
->explicitly specify the version of the image you want to use.
+ the 'latest' docker images work, it is highly recommended to
+ explicitly specify the version of the image you want to use.
Docker images for the Software Heritage stack are tagged with their build date:
.. code-block:: bash
~$ docker images -f reference='softwareheritage/*:20*'
REPOSITORY TAG IMAGE ID CREATED SIZE
softwareheritage web-20200819-112604 32ab8340e368 About an hour ago 339MB
softwareheritage base-20200819-112604 19fe3d7326c5 About an hour ago 242MB
softwareheritage web-20200630-115021 65b1869175ab 7 weeks ago 342MB
softwareheritage base-20200630-115021 3694e3fcf530 7 weeks ago 245MB
To specify the tag to be used, simply set the SWH_IMAGE_TAG environment variable, like:
.. code-block:: bash
export SWH_IMAGE_TAG=20200819-112604
docker deploy -c base-services.yml swh
->[!WARNING]
->make sure to have this variable properly set for any later `docker deploy`
->command you type, otherwise you running containers will be recreated using the
->':latest' image (which might **not** be the latest available version, nor
->consistent amond the docker nodes on you swarm cluster).
+.. warning::
+
+ make sure to have this variable properly set for any later `docker deploy`
+ command you type, otherwise you running containers will be recreated using the
+ ':latest' image (which might **not** be the latest available version, nor
+ consistent amond the docker nodes on you swarm cluster).
Updating a configuration
------------------------
When you modify a configuration file exposed to docker services via the `docker
config` system. Unfortunately, docker does not support updating these config
objects, so you need to either:
- destroy the old config before being able to recreate them. That also means
you need to recreate every docker container using this config, or
- adapt the `name:` field in the compose file.
For example, if you edit the file `conf/storage.yml`:
.. code-block:: bash
~/swh-docker$ docker service rm swh_storage
swh_storage
~/swh-docker$ docker config rm swh_storage
swh_storage
~/swh-docker$ docker stack deploy -c base-services.yml swh
Creating config swh_storage
Creating service swh_storage
Updating service swh_nginx (id: l52hxxl61ijjxnj9wg6ddpaef)
Updating service swh_memcache (id: 2ujcw3dg8f9dm4r6qmgy0sb1e)
Updating service swh_db-storage (id: bkn2bmnapx7wgvwxepume71k1)
Updating service swh_web (id: 7sm6g5ecff1979t0jd3dmsvwz)
Updating service swh_objstorage (id: 3okk2njpbopxso3n3w44ydyf9)
[...]
Note: since persistent data (databases and objects) are stored in volumes, you
can safely destoy and recreate any container you want, you will not loose any
data.
Or you can change the compose file like:
.. code-block:: yaml
[...]
configs:
storage:
file: conf/storage.yml
name: storage-updated # change this as desired
then it's just a matter of redeploying the stack:
.. code-block:: bash
~/swh-docker$ docker stack deploy -c base-services.yml swh
[...]
See https://docs.docker.com/engine/swarm/configs/ for more details on
how to use the config system in a docker swarm cluster.
See https://blog.sunekeller.dk/2019/01/docker-stack-deploy-update-configs/ for
an example of scripting this second solution.
Updating a service
------------------
When a new version of the softwareheritage image is published, running
services must updated to use it.
In order to prevent inconsistency caveats due to dependency in deployed
versions, we recommend that you deploy the new image on all running
services at once.
This can be done as follow:
.. code-block:: bash
~/swh-docker$ export SWH_IMAGE_TAG=
~/swh-docker$ docker stack deploy -c base-services.yml swh
Note that this will reset the replicas config to their default values.
If you want to update only a specific service, you can also use (here for a
replayer service):
.. code-block:: bash
~/swh-docker$ docker service update --image \
softwareheritage/replayer:${SWH_IMAGE_TAG} ) \
swh_graph-replayer
Set up a mirror
===============
->[!WARNING] you cannot "upgrade" an existing docker stack built from the
->base-services.yml file to a mirror one; you need to recreate it; more
->precisely, you need to drop the storage database before. This is due to the
->fact the storage database for a mirror is not initialized the same way as
->the default storage database.
+.. warning::
+
+ you cannot "upgrade" an existing docker stack built from the base-services.yml file
+ to a mirror one; you need to recreate it; more precisely, you need to drop the
+ storage database before. This is due to the fact the storage database for a mirror is
+ not initialized the same way as the default storage database.
A Software Heritage mirror consists in base Software Heritage services, as
described above, without any worker related to web scraping nor source code
repository loading. Instead, filling local storage and objstorage is the
responsibility of kafka based `replayer` services:
- the `graph replayer` which is in charge of filling the storage (aka the
graph), and
- the `content replayer` which is in charge of filling the object storage.
Examples of docker deploy files and configuration files are provided in
the `graph-replayer.yml` deploy file for replayer services
using configuration from yaml files in `conf/graph-replayer.yml`.
Copy these example files as plain yaml ones then modify them to replace
the XXX markers with proper values (also make sure the kafka server list
is up to date.) Parameters to check/update are:
- `journal_client/brokers`: list of kafka brokers.
- `journal_client/group_id`: unique identifier for this mirroring session;
you can choose whatever you want, but changing this value will make kafka
start consuming messages from the beginning; kafka messages are dispatched
among consumers with the same `group_id`, so in order to distribute the
load among workers, they must share the same `group_id`.
- `journal_client/sasl.username`: kafka authentication username.
- `journal_client/sasl.password`: kafka authentication password.
Then you need to merge the compose files "by hand" (due to this still
-[unresolved](https://github.com/docker/cli/issues/1651)
-[bugs](https://github.com/docker/cli/issues/1582)). For this we will use
-[docker-compose](https://github.com/docker/compose) as helper tool to merge the
+`unresolved `_
+`bugs `_). For this we will use
+`docker compose `_ as helper tool to merge the
compose files.
To merge 2 (or more) compose files together, typically `base-services.yml` with
a mirror-related file:
.. code-block:: bash
~/swh-docker$ docker-compose \
-f base-services.yml \
-f graph-replayer-override.yml \
config > mirror.yml
Then use this generated file as argument of the `docker stack deploy` command, e.g.:
.. code-block:: bash
~/swh-docker$ docker stack deploy -c mirror.yml swh-mirror
Graph replayer
--------------
To run the graph replayer compoenent of a mirror:
.. code-block:: bash
~/swh-docker$ cd conf
~/swh-docker/conf$ cp graph-replayer.yml.example graph-replayer.yml
~/swh-docker/conf$ # edit graph-replayer.yml files
~/swh-docker/conf$ cd ..
Once you have properly edited the `conf/graph-replayer.yml` config file, you can
start these services with:
.. code-block:: bash
- ~/swh-docker$ docker-composer \
+ ~/swh-docker$ docker-compose \
-f base-services.yml \
-f graph-replayer-override.yml \
config > graph-replayer.yml
~/swh-docker$ docker stack deploy \
-c graph-replayer.yml \
swh-mirror
[...]
You can check everything is running with:
.. code-block:: bash
~/swh-docker$ docker stack ls
NAME SERVICES ORCHESTRATOR
swh-mirror 11 Swarm
~/swh-docker$ docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
88djaq3jezjm swh-mirror_db-storage replicated 1/1 postgres:11
m66q36jb00xm swh-mirror_grafana replicated 1/1 grafana/grafana:latest
qfsxngh4s2sv swh-mirror_content-replayer replicated 1/1 softwareheritage/replayer:latest
qcl0n3ngr2uv swh-mirror_graph-replayer replicated 1/1 softwareheritage/replayer:latest
zn8dzsron3y7 swh-mirror_memcache replicated 1/1 memcached:latest
wfbvf3yk6t41 swh-mirror_nginx replicated 1/1 nginx:latest *:5081->5081/tcp
thtev7o0n6th swh-mirror_objstorage replicated 1/1 softwareheritage/base:latest
ysgdoqshgd2k swh-mirror_prometheus replicated 1/1 prom/prometheus:latest
u2mjjl91aebz swh-mirror_prometheus-statsd-exporter replicated 1/1 prom/statsd-exporter:latest
xyf2xgt465ob swh-mirror_storage replicated 1/1 softwareheritage/base:latest
su8eka2b5cbf swh-mirror_web replicated 1/1 softwareheritage/web:latest
If everything is OK, you should have your mirror filling. Check docker logs:
.. code-block:: bash
~/swh-docker$ docker service logs swh-mirror_graph-replayer
[...]
or:
.. code-block:: bash
~/swh-docker$ docker service logs --tail 100 --follow swh-mirror_graph-replayer
[...]
Content replayer
----------------
Similarly, to run the content replayer:
.. code-block:: bash
~/swh-docker$ cd conf
~/swh-docker/conf$ cp content-replayer.yml.example content-replayer.yml
~/swh-docker/conf$ # edit content-replayer.yml files
~/swh-docker/conf$ cd ..
Once you have properly edited the `conf/content-replayer.yml` config file, you can
start these services with:
.. code-block:: bash
- ~/swh-docker$ docker-composer \
+ ~/swh-docker$ docker-compose \
-f base-services.yml \
-f content-replayer-override.yml \
config > content-replayer.yml
~/swh-docker$ docker stack deploy \
-c content-replayer.yml \
swh-mirror
[...]
Full mirror
-----------
Putting all together is just a matter of merging the 3 compose files:
.. code-block:: bash
- ~/swh-docker$ docker-composer \
+ ~/swh-docker$ docker-compose \
-f base-services.yml \
-f graph-replayer-override.yml \
-f content-replayer-override.yml \
config > mirror.yml
~/swh-docker$ docker stack deploy \
-c mirror.yml \
swh-mirror
[...]
Scaling up services
-------------------
In order to scale up a replayer service, you can use the `docker scale` command. For example:
.. code-block:: bash
~/swh-docker$ docker service scale swh_graph-replayer=4
[...]
will start 4 copies of the graph replayer service.
Notes:
- One graph replayer service requires a steady 500MB to 1GB of RAM to run, so
make sure you have properly sized machines for running these replayer
containers, and to monitor these.
- The overall bandwidth of the replayer will depend heavily on the
`swh_storage` service, thus on the `swh_db-storage`. It will require some
network bandwidth for the ingress kafka payload (this can easily peak to
several hundreds of Mb/s). So make sure you have a correctly tuned database
and enough network bw.
- Biggest topics are the directory, revision and content.