diff --git a/scripts/devis_proxmox_fw.py b/scripts/devis_proxmox_fw.py
index 9a168df..80d137d 100644
--- a/scripts/devis_proxmox_fw.py
+++ b/scripts/devis_proxmox_fw.py
@@ -121,6 +121,12 @@ def _ports(fl: dict) -> list[str]:
     return fixes
 
 
+# LE REGISTRE PARLE NFTABLES, PROXMOX PARLE IPTABLES (2026-09-29). `frag-needed` est le
+# nom nftables ; l'API Proxmox le refuse (« invalid icmp-type value ») et attend
+# `fragmentation-needed`. Mesure a la premiere application des flux `externe`.
+ICMP_PROXMOX = {"frag-needed": "fragmentation-needed"}
+
+
 def _cibles(fl: dict) -> list[dict]:
     """Ce qu'une regle vise : un port TCP/UDP, ou un TYPE ICMP.
 
@@ -132,7 +138,8 @@ def _cibles(fl: dict) -> list[dict]:
     """
     if str(fl.get("protocole", "tcp")).lower() == "icmp":
         p = fl["port"]
-        return [{"proto": "icmp", "icmp_type": str(t)} for t in (p if isinstance(p, list) else [p])]
+        return [{"proto": "icmp", "icmp_type": ICMP_PROXMOX.get(str(t), str(t))}
+                for t in (p if isinstance(p, list) else [p])]
     return [{"proto": fl.get("protocole", "tcp"), "dport": port} for port in _ports(fl)]