infrastructure/hammerhead

Hammerhead Configuration

Roadmap

0. Prior

   • The OS is fully installed and configured using the os/config Ansible scripts.
   • Nomad and Consul on HammerHead have custom configurations compared to the rest of the cluster. The configuration files os/config/nomad.hcl and os/config/consul.json need to be in sync on the server at /etc/nomad/nomad.hcl and /etc/consul/consul.json respectively.

1. Base components: things that need to be installed before services

   • Dummy HTTP server to have something to work with.

   • Reverse-proxy/load-balancer: nginx is a good match for a one-node deployment. Installing it with Nomad/Consul will make me practice Consul Template etc.

     SSL using nginx is pain. I undrstand the interest of traefik or fabio in that sense: their close collaboration with Nomad allow them to automate certificates generation.

     Consequently, SSL is not supported at the moment. (It would be manual using nginx.)

   • Generate services configuration outside the nginx service definition.

     Can't do because of separation of concerns: files needed by nginx need to be defined in the nginx job specification.

     Solution: each new web service needs:

       * an nginx configuration template at `app/nginx/config`
       * a template stanza in `app/nginx/deploy/nginx.hcl` to interpret the above template configuration. Which is lame.
     

2. Gitea installation

   • persistent data -> host_volume

   • Postgres database

     • Persistent data volume - using host_volume in the client config of Nomad (requires a restart, and it's not so fun to add volumes there).

     • How can Postgres be its own job, while not exposing it publicly and still letting it talk to other jobs? With Consul Connect !

   • Avoid exposing gitea publicly (on port 3000). Can't without heavy configuration of nginx, to leverage sidecars. Adding another service would be even more painful than it already is.

   • SSL. Can't without heavy-lifting, again due to nginx.

   Conclusion: Don't use nginx.

3. Wiki installation

   • Postgres database

4. Gitea migration

   • Postgres database: needs to be its own Nomad job.
   • Gitea: setting it up on Nomad.
   • Migrating data from Serenity, where the DB is MySQL. Expect fun times.
   • Database & files periodic backups

5. Synapse migration

   • Postgres already setup
   • Migrating from a Postgres on Serenity (easier)
   • Backups

6. [Own/Next]cloud: Adrien needs it for himself.

   • Compare distribution capabilities / S3-compatibility between the two solutions. The assumption is that Owncloud's Go rewrite is the better fit.
   • Do the things.