From 3b8d0c44587d25fc7b034dc48e4c8db9259da615 Mon Sep 17 00:00:00 2001
From: Simponic <elizabeth.hunt@simponic.xyz>
Date: Wed, 1 Feb 2023 08:51:20 -0700
Subject: [PATCH] Multicast instead of .hosts.erlang

---
 Dockerfile                         |  4 ----
 buildscripts/build/build.sh        |  5 -----
 buildscripts/build/build_server.sh |  1 -
 config/prod.exs                    | 13 ++++++++++---
 4 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 4e8d647..3650631 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -62,10 +62,6 @@ ENV LC_ALL en_US.UTF-8
 WORKDIR "/app"
 RUN chown nobody /app
 
-# set OTP_ROOT so elixir can find nodes
-ENV OTP_ROOT=/app
-COPY .hosts.erlang /app/.hosts.erlang
-
 # set runner ENV
 ENV MIX_ENV="prod"
 
diff --git a/buildscripts/build/build.sh b/buildscripts/build/build.sh
index 482a577..3cc5717 100755
--- a/buildscripts/build/build.sh
+++ b/buildscripts/build/build.sh
@@ -10,7 +10,6 @@ server_node_ids=(4 5 6)
 build_dir="${HOME}/src/chessh/buildscripts/build"
 
 server_name="chessh.linux.usu.edu"
-erlang_hosts_file="${build_dir}/.hosts.erlang"
 load_balancer_nginx_site_file="/etc/nginx/sites-enabled/${server_name}.conf"
 ha_proxy_cfg_file="/etc/haproxy/haproxy.cfg"
 ssl_cert_path="/etc/letsencrypt/live/${server_name}"
@@ -160,15 +159,11 @@ function build_server() {
     
     scp $ssh_opts "${build_dir}/build_server.sh" $node_conn:~/
 
-    scp $ssh_opts $erlang_hosts_file $node_conn:~/
-
     ssh $ssh_opts $node_conn "~/build_server.sh"
 }
 
 function build_server_nodes() {
     copy_ssh_keys
-    printf "'192.168.100.%s'\n" ${server_node_ids[@]} > $erlang_hosts_file
-    
     for node_id in "${server_node_ids[@]}"
     do
         build_server $node_id
diff --git a/buildscripts/build/build_server.sh b/buildscripts/build/build_server.sh
index 1857e6b..80e6e91 100755
--- a/buildscripts/build/build_server.sh
+++ b/buildscripts/build/build_server.sh
@@ -30,7 +30,6 @@ fi
 # Build
 cd $chessh_path
 [ -d "$chessh_path/priv/keys" ] && cp ~/keys/* "$chessh_path/priv/keys/" || cp -r ~/keys "$chessh_path/priv"
-mv $HOME/.hosts.erlang .
 sudo docker build . -t chessh/server
 
 # Systemd service
diff --git a/config/prod.exs b/config/prod.exs
index 15d52a1..6196da8 100644
--- a/config/prod.exs
+++ b/config/prod.exs
@@ -13,8 +13,15 @@ config :chessh, RateLimits,
 
 config :libcluster,
   topologies: [
-    erlang_hosts_example: [
-      strategy: Elixir.Cluster.Strategy.ErlangHosts,
-      config: [timeout: 30_000]
+    chessh: [
+      strategy: Elixir.Cluster.Strategy.Gossip,
+      config: [
+        port: 45892,
+        if_addr: "0.0.0.0",
+        multicast_if: "192.168.1.1",
+        multicast_addr: "233.252.1.32",
+        multicast_ttl: 1,
+        secret: "chessh"
+      ]
     ]
   ]