diff --git a/host/x86_64-linux/dasha/Network.nix b/host/x86_64-linux/dasha/Network.nix
index 8d4e8367..9719b357 100644
--- a/host/x86_64-linux/dasha/Network.nix
+++ b/host/x86_64-linux/dasha/Network.nix
@@ -4,6 +4,14 @@
 			# Ssh access.
 			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8          -p tcp --dport 22143
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22143
+
+			# Syncthing.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p tcp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 21027
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 21027
 		'';
 	};
 }
diff --git a/host/x86_64-linux/desktop/Network.nix b/host/x86_64-linux/desktop/Network.nix
index bb763fd8..9719b357 100644
--- a/host/x86_64-linux/desktop/Network.nix
+++ b/host/x86_64-linux/desktop/Network.nix
@@ -6,6 +6,9 @@
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22143
 
 			# Syncthing.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p tcp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 21027
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22000
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 22000
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 21027
diff --git a/host/x86_64-linux/laptop/Network.nix b/host/x86_64-linux/laptop/Network.nix
index 8d4e8367..9719b357 100644
--- a/host/x86_64-linux/laptop/Network.nix
+++ b/host/x86_64-linux/laptop/Network.nix
@@ -4,6 +4,14 @@
 			# Ssh access.
 			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8          -p tcp --dport 22143
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22143
+
+			# Syncthing.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p tcp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 21027
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 21027
 		'';
 	};
 }
diff --git a/host/x86_64-linux/max/Network.nix b/host/x86_64-linux/max/Network.nix
new file mode 100644
index 00000000..9719b357
--- /dev/null
+++ b/host/x86_64-linux/max/Network.nix
@@ -0,0 +1,17 @@
+{ ... }: {
+	networking = {
+		firewall.extraCommands = ''
+			# Ssh access.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8          -p tcp --dport 22143
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22143
+
+			# Syncthing.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p tcp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 21027
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 21027
+		'';
+	};
+}
diff --git a/host/x86_64-linux/pocket/Network.nix b/host/x86_64-linux/pocket/Network.nix
index 8d4e8367..9719b357 100644
--- a/host/x86_64-linux/pocket/Network.nix
+++ b/host/x86_64-linux/pocket/Network.nix
@@ -4,6 +4,14 @@
 			# Ssh access.
 			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8          -p tcp --dport 22143
 			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22143
+
+			# Syncthing.
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p tcp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 22000
+			iptables  -I INPUT -j ACCEPT -s 10.0.0.0/8 -p udp --dport 21027
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p tcp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 22000
+			ip6tables -I INPUT -j ACCEPT -s fd09:8d46:0b26::/48 -p udp --dport 21027
 		'';
 	};
 }