diff --git a/tools/tag_obsolete_os.py b/tools/tag_obsolete_os.py
new file mode 100644
index 0000000..aea9b73
--- /dev/null
+++ b/tools/tag_obsolete_os.py
@@ -0,0 +1,109 @@
+"""Tag servers avec OS en fin de support -> licence_support='obsolete'.
+
+Regles EOL (end of life) appliquees :
+ - RHEL 5, 6, 7          (7.9 EOL 2024-06-30)
+ - CentOS 5, 6, 7, 8
+ - Oracle Linux 5, 6, 7
+ - Windows Server 2003, 2008, 2012, 2012 R2
+ - Debian 8, 9, 10       (Debian 10 EOL 2024-06-30)
+ - Ubuntu 12.04, 14.04, 16.04, 18.04
+ - SUSE < 12
+
+N'affecte que licence_support (pas etat). Le patching existant exclut deja
+les serveurs avec licence_support='obsolete'.
+
+Usage:
+    python tools/tag_obsolete_os.py [--dry-run] [--overwrite]
+"""
+import os
+import re
+import argparse
+from sqlalchemy import create_engine, text
+
+DATABASE_URL = os.getenv("DATABASE_URL_DEMO") or os.getenv("DATABASE_URL") \
+    or "postgresql://patchcenter:PatchCenter2026!@localhost:5432/patchcenter_demo"
+
+# Patterns regex (case-insensitive) sur os_version indiquant un OS EOL
+EOL_PATTERNS = [
+    (r"red\s*hat.*(?:release\s+)?[567]\b", "RHEL 5/6/7"),
+    (r"centos.*(?:release\s+)?[5678]\b", "CentOS 5/6/7/8"),
+    (r"oracle.*linux.*(?:release\s+)?[567]\b", "Oracle Linux 5/6/7"),
+    (r"windows.*2003", "Windows 2003"),
+    (r"windows.*2008", "Windows 2008"),
+    (r"windows.*2012", "Windows 2012"),
+    (r"debian.*(?:gnu/linux\s+)?[89]\b", "Debian 8/9"),
+    (r"debian.*(?:gnu/linux\s+)?10\b", "Debian 10"),
+    (r"ubuntu.*1[2468]\.04", "Ubuntu 12.04/14.04/16.04/18.04"),
+    (r"suse.*(?:enterprise.*)?(?:server.*)?(?:sp\d\s*)?1[01]\b", "SUSE 10/11"),
+]
+
+
+def classify(os_version):
+    if not os_version:
+        return None
+    v = os_version.lower()
+    for pattern, label in EOL_PATTERNS:
+        if re.search(pattern, v):
+            return label
+    return None
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--dry-run", action="store_true")
+    parser.add_argument("--overwrite", action="store_true",
+                        help="Remplace licence_support='active' par 'obsolete' (sinon skip les active)")
+    args = parser.parse_args()
+
+    engine = create_engine(DATABASE_URL)
+    print(f"[INFO] DB: {DATABASE_URL.split('@')[-1]}")
+    conn = engine.connect().execution_options(isolation_level="AUTOCOMMIT")
+
+    rows = conn.execute(text("""
+        SELECT id, hostname, os_version, licence_support
+        FROM servers
+        WHERE os_version IS NOT NULL AND os_version != ''
+    """)).fetchall()
+    print(f"[INFO] {len(rows)} serveurs avec os_version")
+
+    stats = {"tagged": 0, "already_obsolete": 0, "not_eol": 0, "skipped_active": 0}
+    by_label = {}
+
+    for r in rows:
+        label = classify(r.os_version)
+        if not label:
+            stats["not_eol"] += 1
+            continue
+        if r.licence_support == "obsolete":
+            stats["already_obsolete"] += 1
+            continue
+        # Si deja 'active' ou 'els', on ne touche pas sauf --overwrite
+        if r.licence_support in ("active", "els") and not args.overwrite:
+            stats["skipped_active"] += 1
+            if args.dry_run:
+                print(f"  SKIP (--overwrite pour forcer): {r.hostname:25s} "
+                      f"[{r.licence_support}] {label} | {r.os_version[:60]}")
+            continue
+
+        by_label[label] = by_label.get(label, 0) + 1
+        if args.dry_run:
+            print(f"  DRY: {r.hostname:25s} [{r.licence_support or 'NULL'}] -> obsolete "
+                  f"({label}) | {r.os_version[:60]}")
+        else:
+            conn.execute(text("UPDATE servers SET licence_support='obsolete' WHERE id=:sid"),
+                         {"sid": r.id})
+        stats["tagged"] += 1
+
+    conn.close()
+    print(f"\n[DONE] Tagges obsolete: {stats['tagged']} | "
+          f"Deja obsolete: {stats['already_obsolete']} | "
+          f"Non-EOL: {stats['not_eol']} | "
+          f"Skip (active/els): {stats['skipped_active']}")
+    if by_label:
+        print("\nRepartition par famille EOL :")
+        for label, n in sorted(by_label.items(), key=lambda x: -x[1]):
+            print(f"  {label:40s} {n}")
+
+
+if __name__ == "__main__":
+    main()