diff --git a/2025/xg-infra-guava.md b/2025/xg-infra-guava.md
index c8ae314..fe5c1ec 100644
--- a/2025/xg-infra-guava.md
+++ b/2025/xg-infra-guava.md
@@ -20,6 +20,7 @@ Dedibox Scaleway Online.net
 # Firewall
 
 * https://wiki.debian.org/DebianFirewall
+* `apt install iptables`
 * `/usr/local/sbin/firewall-enable.sh`
 * `/etc/systemd/system/firewall.service`
 * `systemctl start firewall && sleep 120 && systemctl stop firewall`