From e07969c5070f72d3714d01df4538827c1abac35a Mon Sep 17 00:00:00 2001
From: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Date: Fri, 15 Sep 2023 08:52:49 +0900
Subject: [PATCH] [WIP] Support Rocky Linux 9 hosts

VXLAN still does not seem to work

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
---
 Makefile.d/check-preflight.sh |  2 +-
 README.md                     | 14 ++++++++++----
 docker-compose.yaml           |  2 ++
 hack/init-host.root.sh        | 14 +++++++++++++-
 4 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/Makefile.d/check-preflight.sh b/Makefile.d/check-preflight.sh
index 3978498..6986dd6 100755
--- a/Makefile.d/check-preflight.sh
+++ b/Makefile.d/check-preflight.sh
@@ -59,7 +59,7 @@ else
 fi
 
 # Check kernel modules
-for f in ip6_tables ip6table_nat ip_tables iptable_nat vxlan; do
+for f in br_netfilter ip6_tables ip6table_nat ip_tables iptable_nat vxlan; do
 	if ! grep -qw "^$f" /proc/modules; then
 		WARNING "Kernel module \"${f}\" does not seem loaded? (negligible if built-in to the kernel)"
 	fi
diff --git a/README.md b/README.md
index 8c015f9..0bd2046 100644
--- a/README.md
+++ b/README.md
@@ -22,9 +22,10 @@ but Usernetes (Gen 2) supports creating a cluster with multiple hosts.
 
 ## Requirements
 
-> **Note**
->
-> Using Ubuntu 22.04 hosts is recommended.
+- Host OS should be one of the following:
+  - Ubuntu 22.04 (recommended)
+  - Rocky Linux 9
+  - AlmaLinux 9
 
 - [Rootless Docker](https://rootlesscontaine.rs/getting-started/docker/):
 ```bash
@@ -52,7 +53,12 @@ sudo systemctl daemon-reload
 
 - Kernel modules:
 ```
-sudo modprobe vxlan
+sudo tee /etc/modules-load.d/usernetes.conf <<EOF >/dev/null
+br_netfilter
+vxlan
+EOF
+
+sudo systemctl restart systemd-modules-load.service
 ```
 
 ## Usage
diff --git a/docker-compose.yaml b/docker-compose.yaml
index 9e17676..98fa77c 100644
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -32,6 +32,8 @@ services:
     environment:
       KUBECONFIG: /etc/kubernetes/admin.conf
       U7S_HOST_IP: ${U7S_HOST_IP}
+    sysctls:
+      - net.ipv4.ip_forward=1
 networks:
   default:
     ipam:
diff --git a/hack/init-host.root.sh b/hack/init-host.root.sh
index 20abb9c..b59296a 100755
--- a/hack/init-host.root.sh
+++ b/hack/init-host.root.sh
@@ -15,8 +15,20 @@ EOF
 	systemctl daemon-reload
 fi
 
+cat >/etc/modules-load.d/usernetes.conf <<EOF
+br_netfilter
+vxlan
+EOF
+systemctl restart systemd-modules-load.service
+
 if ! command -v dockerd-rootless-setuptool.sh >/dev/null 2>&1; then
-	curl https://get.docker.com | sh
+	if grep -q centos /etc/os-release; then
+		# Works with Rocky and Alma too
+		dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo
+		dnf -y install docker-ce
+	else
+		curl https://get.docker.com | sh
+	fi
 fi
 systemctl disable --now docker