Add check_dockers

This commit is contained in:
gru
2026-03-20 13:16:57 +01:00
parent dcd0e534e1
commit dfc7035c78

346
check_dockers Normal file
View File

@@ -0,0 +1,346 @@
#!/usr/bin/env python3
import configparser
import json
import os
import subprocess
import sys
from typing import Dict, List, Tuple
CONFIG_PATH = "/etc/docker-monitoring/containers.ini"
def run(cmd: List[str]) -> Tuple[int, str, str]:
p = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
return p.returncode, p.stdout.strip(), p.stderr.strip()
def nagios_exit(code: int, msg: str):
print(msg)
sys.exit(code)
def ensure_dir(path: str):
d = os.path.dirname(path)
if d and not os.path.isdir(d):
os.makedirs(d, exist_ok=True)
def parse_bool(v: str, default: bool = False) -> bool:
if v is None:
return default
return str(v).strip().lower() in ("1", "true", "yes", "on")
def parse_float(v: str, default: float = 0.0) -> float:
try:
return float(str(v).strip())
except Exception:
return default
def docker_available() -> bool:
rc, _, _ = run(["docker", "info", "--format", "{{json .}}"])
return rc == 0
def list_containers_all() -> List[str]:
rc, out, err = run(["docker", "ps", "-a", "--format", "{{.Names}}"])
if rc != 0:
nagios_exit(3, f"UNKNOWN - cannot list containers: {err}")
return [x.strip() for x in out.splitlines() if x.strip()]
def inspect_container(name: str) -> Dict:
rc, out, _ = run(["docker", "inspect", name])
if rc != 0:
return {}
try:
arr = json.loads(out)
return arr[0] if arr else {}
except Exception:
return {}
def detect_container_type(inspect: Dict) -> str:
labels = (inspect.get("Config") or {}).get("Labels") or {}
if "com.docker.compose.project" in labels:
return "compose"
if "com.docker.stack.namespace" in labels:
return "stack"
return "standalone"
def get_ip(inspect: Dict) -> str:
nets = ((inspect.get("NetworkSettings") or {}).get("Networks") or {})
for _, v in nets.items():
ip = v.get("IPAddress")
if ip:
return ip
return "-"
def get_started_at(inspect: Dict) -> str:
return ((inspect.get("State") or {}).get("StartedAt")) or "-"
def get_restart_count(inspect: Dict) -> int:
try:
return int(inspect.get("RestartCount", 0))
except Exception:
return 0
def get_running(inspect: Dict) -> bool:
return bool(((inspect.get("State") or {}).get("Running")))
def get_status_text(inspect: Dict) -> str:
return ((inspect.get("State") or {}).get("Status")) or "unknown"
def create_default_config(path: str):
ensure_dir(path)
cfg = configparser.ConfigParser()
cfg["global"] = {
"monitor_resources": "true",
"default_cpu_warn": "80",
"default_cpu_crit": "95",
"default_mem_warn": "80",
"default_mem_crit": "95",
"default_restart_warn": "5",
"default_restart_crit": "20",
"skip_types": "compose,stack",
}
for name in list_containers_all():
info = inspect_container(name)
ctype = detect_container_type(info)
labels = (info.get("Config") or {}).get("Labels") or {}
section = {
"enabled": "true",
"type": ctype,
"monitor_liveness": "true",
"monitor_resources": "true",
"cpu_warn": "",
"cpu_crit": "",
"mem_warn": "",
"mem_crit": "",
"restart_warn": "",
"restart_crit": "",
}
if ctype == "compose":
section["note"] = f"auto-detected compose project: {labels.get('com.docker.compose.project', '-')}"
elif ctype == "stack":
section["note"] = f"auto-detected stack: {labels.get('com.docker.stack.namespace', '-')}"
cfg[name] = section
with open(path, "w") as f:
cfg.write(f)
def load_or_create_config(path: str) -> configparser.ConfigParser:
if not os.path.exists(path):
create_default_config(path)
cfg = configparser.ConfigParser()
cfg.read(path)
if "global" not in cfg:
cfg["global"] = {
"monitor_resources": "true",
"default_cpu_warn": "80",
"default_cpu_crit": "95",
"default_mem_warn": "80",
"default_mem_crit": "95",
"default_restart_warn": "5",
"default_restart_crit": "20",
"skip_types": "compose,stack",
}
return cfg
def get_stats_one_shot() -> Dict[str, Dict[str, str]]:
cmd = [
"docker", "stats", "--no-stream",
"--format", "{{.Name}}|{{.CPUPerc}}|{{.MemPerc}}|{{.MemUsage}}"
]
rc, out, _ = run(cmd)
if rc != 0:
return {}
stats = {}
for line in out.splitlines():
parts = line.split("|", 3)
if len(parts) != 4:
continue
name, cpu, memp, memu = parts
stats[name.strip()] = {
"cpu": cpu.strip().replace("%", ""),
"mem_perc": memp.strip().replace("%", ""),
"mem_usage": memu.strip(),
}
return stats
def state_max(a: int, b: int) -> int:
return a if a > b else b
def evaluate_container(
name: str,
section: configparser.SectionProxy,
global_cfg: configparser.SectionProxy,
stats: Dict[str, Dict[str, str]]
) -> Tuple[int, str]:
info = inspect_container(name)
if not info:
return 2, f"CRITICAL - {name} container not found"
running = get_running(info)
status_txt = get_status_text(info)
ip = get_ip(info)
started = get_started_at(info)
restarts = get_restart_count(info)
code = 0
messages = []
monitor_liveness = parse_bool(section.get("monitor_liveness", "true"), True)
monitor_resources = parse_bool(
section.get("monitor_resources", global_cfg.get("monitor_resources", "true")),
True
)
if monitor_liveness:
if running:
messages.append(f"OK - {name} is running. IP: {ip}, StartedAt: {started}")
else:
code = 2
messages.append(f"CRITICAL - {name} is not running (status: {status_txt})")
restart_warn = parse_float(section.get("restart_warn") or global_cfg.get("default_restart_warn", "5"), 5)
restart_crit = parse_float(section.get("restart_crit") or global_cfg.get("default_restart_crit", "20"), 20)
if restarts >= restart_crit:
code = state_max(code, 2)
messages.append(f"CRITICAL - {name} restart count {restarts} >= {restart_crit}")
elif restarts >= restart_warn:
code = state_max(code, 1)
messages.append(f"WARNING - {name} restart count {restarts} >= {restart_warn}")
if monitor_resources and name in stats:
cpu = parse_float(stats[name].get("cpu", "0"), 0)
memp = parse_float(stats[name].get("mem_perc", "0"), 0)
memu = stats[name].get("mem_usage", "-")
cpu_warn = parse_float(section.get("cpu_warn") or global_cfg.get("default_cpu_warn", "80"), 80)
cpu_crit = parse_float(section.get("cpu_crit") or global_cfg.get("default_cpu_crit", "95"), 95)
mem_warn = parse_float(section.get("mem_warn") or global_cfg.get("default_mem_warn", "80"), 80)
mem_crit = parse_float(section.get("mem_crit") or global_cfg.get("default_mem_crit", "95"), 95)
if cpu >= cpu_crit:
code = state_max(code, 2)
messages.append(f"CRITICAL - {name} CPU {cpu:.1f}% >= {cpu_crit}%")
elif cpu >= cpu_warn:
code = state_max(code, 1)
messages.append(f"WARNING - {name} CPU {cpu:.1f}% >= {cpu_warn}%")
if memp >= mem_crit:
code = state_max(code, 2)
messages.append(f"CRITICAL - {name} MEM {memp:.1f}% >= {mem_crit}% ({memu})")
elif memp >= mem_warn:
code = state_max(code, 1)
messages.append(f"WARNING - {name} MEM {memp:.1f}% >= {mem_warn}% ({memu})")
if code == 0:
return 0, f"OK - {name} is running. IP: {ip}, StartedAt: {started}"
return code, " ; ".join(messages)
def main():
config_path = CONFIG_PATH
verbose = False
i = 1
while i < len(sys.argv):
arg = sys.argv[i]
if arg in ("-c", "--config") and i + 1 < len(sys.argv):
config_path = sys.argv[i + 1]
i += 2
continue
elif arg in ("--init", "--init-only"):
create_default_config(config_path)
print(f"Created {config_path}")
sys.exit(0)
elif arg in ("-v", "--verbose"):
verbose = True
i += 1
if not docker_available():
nagios_exit(3, "UNKNOWN - docker is not available or permission denied")
cfg = load_or_create_config(config_path)
global_cfg = cfg["global"]
stats = get_stats_one_shot()
enabled = []
for sec in cfg.sections():
if sec == "global":
continue
if parse_bool(cfg[sec].get("enabled", "false"), False):
enabled.append(sec)
if not enabled:
nagios_exit(3, f"UNKNOWN - no enabled containers in {config_path}")
overall = 0
ok_msgs = []
warn_msgs = []
crit_msgs = []
for name in enabled:
code, txt = evaluate_container(name, cfg[name], global_cfg, stats)
overall = state_max(overall, code)
if code == 0:
ok_msgs.append(txt)
elif code == 1:
warn_msgs.append(txt)
elif code == 2:
crit_msgs.append(txt)
ok_count = len(ok_msgs)
warn_count = len(warn_msgs)
crit_count = len(crit_msgs)
total = len(enabled)
perfdata = f"containers_ok={ok_count} containers_warning={warn_count} containers_critical={crit_count}"
if overall == 0:
if verbose:
print(f"OK - checked {total} container(s), all running | {perfdata}")
print("\n".join(ok_msgs))
else:
print(f"OK - checked {total} container(s), all running | {perfdata}")
sys.exit(0)
prefix = "WARNING" if overall == 1 else "CRITICAL"
print(f"{prefix} - checked {total} container(s): {crit_count} critical, {warn_count} warning, {ok_count} ok | {perfdata}")
details = crit_msgs + warn_msgs
if verbose:
details += ok_msgs
if details:
print("\n".join(details))
sys.exit(overall)
if __name__ == "__main__":
main()