사용 방법
- 설치 명령을 복사하고 자신의 에이전트 환경에 설치하기 전에 소스 패키지를 확인하세요.
- 필요한 도구, 인증 정보, 지원 환경은 원본 문서에서 확인하세요.
- 입력과 원하는 산출물을 설명하고 출처와 결과를 대조하세요.
npx skills add https://github.com/affaan-m/ecc --skill network-config-validation시작 전 확인
- 설치에는 모델 구독, API 한도, 파일 접근 권한이 포함되지 않습니다.
- 별점 수와 설치 수는 활동 지표이며 독립적인 품질·보안 검증이 아닙니다.
원본 Skill 문서
원본 저장소의 제목, 예시, 코드, 표, 링크, 이미지를 유지해 표시합니다.
Network Config Validation
Use this skill to review network configuration before a change window or before an automation run touches production devices.
When to Use
- Reviewing Cisco IOS or IOS-XE style snippets before deployment.
- Auditing generated config from scripts or templates.
- Looking for dangerous commands, duplicate IP addresses, or subnet overlaps.
- Checking whether ACLs, route-maps, prefix-lists, or line policies are referenced
but not defined.
- Building lightweight pre-flight scripts for network automation.
How It Works
Treat config validation as layered evidence, not as a complete parser. Regex checks are useful for pre-flight warnings, but final approval still needs a network engineer to review intent, platform syntax, and rollback steps.
Validate in this order:
- Destructive commands.
- Credential and management-plane exposure.
- Duplicate addresses and overlapping subnets.
- Stale references to ACLs, route-maps, prefix-lists, and interfaces.
- Operational hygiene such as NTP, timestamps, remote logging, and banners.
Dangerous Command Detection
python
import re
DANGEROUS_PATTERNS: list[tuple[re.Pattern[str], str]] = [
(re.compile(r"\breload\b", re.I), "reload causes downtime"),
(re.compile(r"\berase\s+(startup|nvram|flash)", re.I), "erases persistent storage"),
(re.compile(r"\bformat\b", re.I), "formats a device filesystem"),
(re.compile(r"\bno\s+router\s+(bgp|ospf|eigrp)\b", re.I), "removes a routing process"),
(re.compile(r"\bno\s+interface\s+\S+", re.I), "removes interface configuration"),
(re.compile(r"\baaa\s+new-model\b", re.I), "changes authentication behavior"),
(re.compile(r"\bcrypto\s+key\s+(zeroize|generate)\b", re.I), "changes device SSH keys"),
]
def find_dangerous_commands(lines: list[str]) -> list[dict[str, str | int]]:
findings = []
for line_number, line in enumerate(lines, start=1):
stripped = line.strip()
for pattern, reason in DANGEROUS_PATTERNS:
if pattern.search(stripped):
findings.append({
"line": line_number,
"command": stripped,
"reason": reason,
})
return findingsDuplicate IPs And Subnet Overlaps
python
import ipaddress
import re
from collections import Counter
IP_ADDRESS_RE = re.compile(
r"^\s*ip address\s+"
r"(?P<ip>\d{1,3}(?:\.\d{1,3}){3})\s+"
r"(?P<mask>\d{1,3}(?:\.\d{1,3}){3})\b",
re.I | re.M,
)
def extract_interfaces(config: str) -> list[dict[str, str]]:
results = []
current = None
for line in config.splitlines():
if line.startswith("interface "):
current = line.split(maxsplit=1)[1]
continue
match = IP_ADDRESS_RE.match(line)
if current and match:
ip = match.group("ip")
mask = match.group("mask")
network = ipaddress.ip_interface(f"{ip}/{mask}").network
results.append({"interface": current, "ip": ip, "network": str(network)})
return results
def find_duplicate_ips(config: str) -> list[str]:
ips = [entry["ip"] for entry in extract_interfaces(config)]
counts = Counter(ips)
return sorted(ip for ip, count in counts.items() if count > 1)
def find_subnet_overlaps(config: str) -> list[tuple[str, str]]:
networks = [ipaddress.ip_network(entry["network"]) for entry in extract_interfaces(config)]
overlaps = []
for index, left in enumerate(networks):
for right in networks[index + 1:]:
if left.overlaps(right):
overlaps.append((str(left), str(right)))
return overlapsManagement-Plane Checks
Parse VTY blocks by section so access-class checks do not spill across unrelated lines.
python
import re
def iter_blocks(config: str, starts_with: str) -> list[str]:
blocks = []
current: list[str] = []
for line in config.splitlines():
if line.startswith(starts_with):
if current:
blocks.append("\n".join(current))
current = [line]
continue
if current:
if line and not line.startswith(" "):
blocks.append("\n".join(current))
current = []
else:
current.append(line)
if current:
blocks.append("\n".join(current))
return blocks
def check_vty_blocks(config: str) -> list[str]:
issues = []
for block in iter_blocks(config, "line vty"):
if re.search(r"transport\s+input\s+.*telnet", block, re.I):
issues.append("VTY allows Telnet; require SSH only.")
if not re.search(r"\baccess-class\s+\S+\s+in\b", block, re.I):
issues.append("VTY block has no inbound access-class source restriction.")
if not re.search(r"\bexec-timeout\s+\d+\s+\d+\b", block, re.I):
issues.append("VTY block has no explicit exec-timeout.")
return issuesSecurity Hygiene Checks
python
SECURITY_PATTERNS = [
(re.compile(r"\bsnmp-server community\s+(public|private)\b", re.I),
"default SNMP community configured"),
(re.compile(r"\bsnmp-server community\s+\S+", re.I),
"SNMPv2 community string configured; prefer SNMPv3 authPriv"),
(re.compile(r"\bip ssh version 1\b", re.I),
"SSH version 1 enabled"),
(re.compile(r"\benable password\b", re.I),
"enable password is present; use enable secret"),
(re.compile(r"\busername\s+\S+\s+password\b", re.I),
"local username uses password instead of secret"),
]
BEST_PRACTICE_PATTERNS = [
(re.compile(r"\bntp server\b", re.I), "NTP server"),
(re.compile(r"\bservice timestamps\b", re.I), "log timestamps"),
(re.compile(r"\blogging\s+\S+", re.I), "logging destination or buffer"),
(re.compile(r"\bsnmp-server group\s+\S+\s+v3\s+priv\b", re.I), "SNMPv3 authPriv group"),
(re.compile(r"\bbanner\s+(login|motd)\b", re.I), "login banner"),
]
def check_security(config: str) -> list[str]:
return [message for pattern, message in SECURITY_PATTERNS if pattern.search(config)]
def check_missing_hygiene(config: str) -> list[str]:
return [
f"Missing {description}"
for pattern, description in BEST_PRACTICE_PATTERNS
if not pattern.search(config)
]Examples
Change-Window Preflight
- Run dangerous-command checks on the exact snippet to be pasted.
- Run duplicate IP and subnet overlap checks against the full candidate config.
- Confirm every referenced ACL, route-map, and prefix-list exists.
- Confirm rollback commands and out-of-band access before any management-plane
change.
Automation Preflight
Use validation as a blocking gate before Netmiko, NAPALM, Ansible, or vendor API automation pushes a generated config. Fail closed on dangerous commands and credentials. Warn on best-practice gaps that are outside the change scope.
Anti-Patterns
- Treating regex validation as a device parser.
- Applying generated config without a dry-run diff.
- Recommending SNMPv2 community strings as a monitoring requirement.
- Checking VTY blocks with regex that can accidentally span unrelated sections.
- Testing firewall behavior by disabling ACLs instead of reading counters/logs.
See Also
- Agent:
network-config-reviewer - Agent:
network-troubleshooter - Skill:
network-interface-health
