观察
观察
systemctl status app-web --no-pager | head -20
journalctl -u app-web --since '30 min ago' | tail -50
systemctl show app-web -p NRestarts -p Restart
systemctl show app-web -p ExecMainStartTimestamp核对与复位
核对与复位
systemctl show app-web -p ExecStart -p User -p Environment
# 常见原因：配置错误、依赖未起、端口被占、内存超限被 OOM
systemctl reset-failed app-web && systemctl start app-web高频重启会放大资源与日志压力：必要时完把 Restart 置 no 或用 StartLimitBurst 限流稳住现场。