diff --git a/farmq-admin/app.py b/farmq-admin/app.py
index d81fcaa..45494c2 100644
--- a/farmq-admin/app.py
+++ b/farmq-admin/app.py
@@ -415,22 +415,23 @@ def create_app(config_name=None):
             # FARMQ 데이터베이스에 약국 생성
             farmq_session = get_farmq_session()
             try:
-                # pharmacy_code 자동 생성 (P001~P999)
-                last_pharmacy = farmq_session.query(PharmacyInfo)\
+                # pharmacy_code 자동 생성 (P0001~P9999)
+                # P + 4자리 숫자 형식만 필터링
+                all_pharmacies = farmq_session.query(PharmacyInfo)\
                     .filter(PharmacyInfo.pharmacy_code.like('P%'))\
-                    .order_by(PharmacyInfo.pharmacy_code.desc())\
-                    .first()
+                    .all()
 
-                if last_pharmacy and last_pharmacy.pharmacy_code:
-                    try:
-                        last_num = int(last_pharmacy.pharmacy_code[1:])
-                        new_num = last_num + 1
-                    except:
-                        new_num = 1
-                else:
-                    new_num = 1
+                max_num = 0
+                for pharmacy in all_pharmacies:
+                    code = pharmacy.pharmacy_code
+                    # P + 정확히 4자리 숫자 형식만 체크 (P0001, P0002, P0003...)
+                    if code and len(code) == 5 and code[0] == 'P' and code[1:].isdigit():
+                        num = int(code[1:])
+                        if num > max_num:
+                            max_num = num
 
-                pharmacy_code = f"P{new_num:03d}"  # P001, P002, ...
+                new_num = max_num + 1
+                pharmacy_code = f"P{new_num:04d}"  # P0001, P0002, ...
 
                 new_pharmacy = PharmacyInfo(
                     pharmacy_code=pharmacy_code,
@@ -445,9 +446,11 @@ def create_app(config_name=None):
                     owner_license=data.get('owner_license', '').strip(),
                     owner_phone=data.get('owner_phone', '').strip(),
                     owner_email=data.get('owner_email', '').strip(),
-                    institution_code=data.get('institution_code', '').strip() or None,
+                    # 요양기관부호: hira_code 우선, 없으면 institution_code 사용
+                    institution_code=(data.get('hira_code', '').strip() or data.get('institution_code', '').strip()) or None,
                     institution_type=data.get('institution_type', '').strip() or None,
                     api_port=data.get('api_port', 8082),
+                    tailscale_ip=data.get('vpn_ip', '').strip() or None,  # VPN IP (선택)
 
                     # 기존 필드
                     proxmox_host=data.get('proxmox_host', '').strip(),
diff --git a/quick-install.sh b/quick-install.sh
index e0617c1..c68d141 100755
--- a/quick-install.sh
+++ b/quick-install.sh
@@ -403,6 +403,15 @@ verify_connection() {
     # 연결된 노드 확인
     print_info "네트워크 상태:"
     tailscale status | head -10
+
+    # 외부 DNS 해석 테스트
+    print_status "외부 DNS 해석 테스트 중..."
+    if ping -c 1 -W 5 google.com >/dev/null 2>&1; then
+        print_success "외부 DNS 해석 정상! (google.com)"
+    else
+        print_warning "외부 DNS 해석 실패. 수동 확인이 필요할 수 있습니다."
+        print_info "문제 해결: resolvectl status 명령으로 DNS 상태를 확인하세요."
+    fi
 }
 
 # ================================
@@ -435,6 +444,42 @@ configure_firewall() {
     print_success "방화벽 설정 완료"
 }
 
+# ================================
+# DNS Fallback 설정 (외부 도메인 해석 보장)
+# ================================
+configure_dns_fallback() {
+    print_status "DNS Fallback 설정 중..."
+
+    # systemd-resolved가 있는 경우에만 설정
+    if systemctl is-active --quiet systemd-resolved 2>/dev/null; then
+        # Fallback DNS 설정 파일 생성
+        mkdir -p /etc/systemd/resolved.conf.d
+        cat > /etc/systemd/resolved.conf.d/headscale-fallback.conf << 'DNSEOF'
+# Headscale MagicDNS Fallback 설정
+# MagicDNS(100.100.100.100) 실패 시 외부 DNS로 폴백
+[Resolve]
+FallbackDNS=1.1.1.1 8.8.8.8 168.126.63.1
+DNSEOF
+
+        # systemd-resolved 재시작
+        systemctl restart systemd-resolved 2>/dev/null || true
+        print_success "DNS Fallback 설정 완료 (1.1.1.1, 8.8.8.8, 168.126.63.1)"
+    else
+        print_info "systemd-resolved가 없습니다. Fallback DNS 설정을 건너뜁니다."
+
+        # /etc/resolv.conf 직접 수정 (비-systemd 시스템용)
+        if [ -f /etc/resolv.conf ] && ! grep -q "1.1.1.1" /etc/resolv.conf 2>/dev/null; then
+            print_info "resolv.conf에 백업 DNS 추가..."
+            # 기존 내용 백업
+            cp /etc/resolv.conf /etc/resolv.conf.backup.$(date +%Y%m%d) 2>/dev/null || true
+            # nameserver 추가 (끝에)
+            echo "# Fallback DNS for Headscale" >> /etc/resolv.conf
+            echo "nameserver 1.1.1.1" >> /etc/resolv.conf
+            echo "nameserver 8.8.8.8" >> /etc/resolv.conf
+        fi
+    fi
+}
+
 # ================================
 # 정리 작업
 # ================================
@@ -503,6 +548,7 @@ main() {
     
     # 사후 설정
     configure_firewall
+    configure_dns_fallback
     verify_connection
     
     # 정리 및 완료