nginx

# 排查后端服务都挂的情况
tail -n 2000 error.log| grep 'no live upstreams while connecting to upstream' | wc -l

# 响应时间排序
tail -n 30000 access.log | awk '{print $5}' | sort -r | head

# 刷新日志文件
kill -USR1 $(cat /opt/nginx/logs/nginx.pid)