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+# Additional README
+
+## Configuring the OS
+
+This repo contains a bunch of scripts to configure NixOS on all cluster nodes.
+Most scripts are invoked with the following syntax:
+
+- for scripts that generate secrets: `./gen_<something> <cluster_name>` to generate the secrets to be used on cluster `<cluster_name>`
+- for deployment scripts:
+  - `./deploy_<something> <cluster_name>` to run the deployment script on all nodes of the cluster `<cluster_name>`
+  - `./deploy_<something> <cluster_name> <node1> <node2> ...` to run the deployment script only on nodes `node1, node2, ...` of cluster `<cluster_name>`.
+
+All deployment scripts can use the following parameters passed as environment variables:
+
+- `SUDO_PASS`: optionnally, the password for `sudo` on cluster nodes. If not set, it will be asked at the begninning.
+- `SSH_USER`: optionnally, the user to try to login using SSH. If not set, the username from your local machine will be used.
+
+### Assumptions (how to setup your environment)
+
+- you have an SSH access to all of your cluster nodes (listed in `cluster/<cluster_name>/ssh_config`)
+
+- your account is in group `wheel` and you know its password (you need it to become root using `sudo`);
+  the password is the same on all cluster nodes (see below for password management tools)
+
+- you have a clone of the secrets repository in your `pass` password store, for instance at `~/.password-store/deuxfleurs`
+  (scripts in this repo will read and write all secrets in `pass` under `deuxfleurs/cluster/<cluster_name>/`)
+
+### Deploying the NixOS configuration
+
+The NixOS configuration makes use of a certain number of files:
+
+- files in `nix/` that are the same for all deployments on all clusters
+- the file `cluster/<cluster_name>/cluster.nix`, a Nix configuration file that is specific to the cluster but is copied the same on all cluster nodes
+- files in `cluster/<cluster_name>/site/`, which are specific to the various sites on which Nix nodes are deployed
+- files in `cluster/<cluster_name>/node/` which are specific to each node
+
+To deploy the NixOS configuration on the cluster, simply do:
+
+```
+./deploy_nixos <cluster_name>
+```
+
+or to deploy only on a single node:
+
+```
+./deploy_nixos <cluster_name> <node_name>
+```
+
+To upgrade NixOS, use the `./upgrade_nixos` script instead (it has the same syntax).
+
+**When adding a node to the cluster:** just do `./deploy_nixos <cluster_name> <name_of_new_node>`
+
+### Generating and deploying a PKI for Consul and Nomad
+
+This is very similar to how we do for Wesher.
+
+First, if the PKI has not yet been created, create it with:
+
+```
+./gen_pki <cluster_name>
+```
+
+Then, deploy the PKI on all nodes with:
+
+```
+./deploy_pki <cluster_name>
+```
+
+**When adding a node to the cluster:** just do `./deploy_pki <cluster_name> <name_of_new_node>`
+
+### Adding administrators and password management
+
+Adminstrators are defined in the `cluster.nix` file for each cluster (they could also be defined in the site-specific Nix files if necessary).
+This is where their public SSH keys for remote access are put.
+
+Administrators will also need passwords to administrate the cluster, as we are not using passwordless sudo.
+To set the password for a new administrator, they must have a working `pass` installation as specified above.
+They must then run:
+
+```
+./passwd <cluster_name> <user_name>
+```
+
+to set their password in the `pass` database (the password is hashed, so other administrators cannot learn their password even if they have access to the `pass` db).
+
+Then, an administrator that already has root access must run the following (after syncing the `pass` db) to set the password correctly on all cluster nodes:
+
+```
+./deploy_passwords <cluster_name>
+```
+
+## Deploying stuff on Nomad
+
+### Connecting to Nomad
+
+Connect using SSH to one of the cluster nodes, forwarding port 14646 to port 4646 on localhost, and port 8501 to port 8501 on localhost.
+
+You can for instance use an entry in your `~/.ssh/config` that looks like this:
+
+```
+Host caribou
+	HostName 2a01:e0a:c:a720::23
+	LocalForward 14646 127.0.0.1:4646
+	LocalForward 8501 127.0.0.1:8501
+	LocalForward 1389 bottin.service.staging.consul:389
+```
+
+Then, in a separate window, launch `./tlsproxy <cluster_name>`: this will
+launch `socat` proxies that strip the TLS layer and allow you to simply access
+Nomad and Consul on the regular, unencrypted URLs: `http://localhost:4646` for
+Nomad and `http://localhost:8500` for Consul.  Keep this terminal window for as
+long as you need to access Nomad and Consul on the cluster.
+
+### Launching services
+
+Stuff should be started in this order:
+
+1. `app/core`
+2. `app/frontend`
+3. `app/telemetry`
+4. `app/garage-staging`
+5. `app/directory`
+
+Then, other stuff can be started in any order:
+
+- `app/im` (cluster `staging` only)
+- `app/cryptpad` (cluster `prod` only)
+- `app/drone-ci`
+