今天一早来公司使用系统， 突然报异常， 提示某个文件不能写入了，这是....什么情况？原先就已经分配过文件写入权限了。
赶紧上CentOS Server上查下情况：
代码语言：javascript复制[zhou@mydata ~]$ df -l
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/xvda1 20641404 10565932 9026948 54% /
tmpfs 4029028 0 4029028 0% /dev/shm
/dev/xvdb1 103210940 67011820 30956312 97% /hotdata原来是磁盘空间满了， 经过一番查阅， 发现日志系统文件占用了好几个G的空间，日志包含Nginx 和 Tomcat logs
du -h --max-depth=1:查看该目录空间占用
du -sh *:查看该目录下所有文件及目录的大小
在tomcat目录下conf/logging.properties 这个文件控制tomcat自带的各种日志文件（安装目录/logs目录下的日志文件），这些文件的配置和管理会影响tomcat日常运行过程中对内存的消耗。
先来看看这个conf/logging.properties 文件：
代码语言：javascript复制[zhou@izbplay.. conf]$ cat logging.properties
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
handlers = 1catalina.org.apache.juli.AsyncFileHandler, 2localhost.org.apache.jul i.AsyncFileHandler, 3manager.org.apache.juli.AsyncFileHandler, 4host-manager.org .apache.juli.AsyncFileHandler, java.util.logging.ConsoleHandler
.handlers = 1catalina.org.apache.juli.AsyncFileHandler, java.util.logging.Consol eHandler
############################################################
# Handler specific properties.
# Describes specific configuration info for Handlers.
############################################################
1catalina.org.apache.juli.AsyncFileHandler.level = FINE
1catalina.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
1catalina.org.apache.juli.AsyncFileHandler.prefix = catalina.
1catalina.org.apache.juli.AsyncFileHandler.maxDays = 90
1catalina.org.apache.juli.AsyncFileHandler.encoding = UTF-8
2localhost.org.apache.juli.AsyncFileHandler.level = FINE
2localhost.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
2localhost.org.apache.juli.AsyncFileHandler.prefix = localhost.
2localhost.org.apache.juli.AsyncFileHandler.maxDays = 90
2localhost.org.apache.juli.AsyncFileHandler.encoding = UTF-8
3manager.org.apache.juli.AsyncFileHandler.level = FINE
3manager.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
3manager.org.apache.juli.AsyncFileHandler.prefix = manager.
3manager.org.apache.juli.AsyncFileHandler.maxDays = 90
3manager.org.apache.juli.AsyncFileHandler.encoding = UTF-8
4host-manager.org.apache.juli.AsyncFileHandler.level = FINE
4host-manager.org.apache.juli.AsyncFileHandler.directory = ${catalina.base}/logs
4host-manager.org.apache.juli.AsyncFileHandler.prefix = host-manager.
4host-manager.org.apache.juli.AsyncFileHandler.maxDays = 90
4host-manager.org.apache.juli.AsyncFileHandler.encoding = UTF-8
java.util.logging.ConsoleHandler.level = FINE
java.util.logging.ConsoleHandler.formatter = org.apache.juli.OneLineFormatter
java.util.logging.ConsoleHandler.encoding = UTF-8
############################################################
# Facility specific properties.
# Provides extra control for each logger.
############################################################
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].level = INFO
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].handlers = 2localh ost.org.apache.juli.AsyncFileHandler
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager].level = INFO
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager].handler s = 3manager.org.apache.juli.AsyncFileHandler
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager].le vel = INFO
org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager].ha ndlers = 4host-manager.org.apache.juli.AsyncFileHandler
# For example, set the org.apache.catalina.util.LifecycleBase logger to log
# each component that extends LifecycleBase changing state:
#org.apache.catalina.util.LifecycleBase.level = FINE
# To see debug messages in TldLocationsCache, uncomment the following line:
#org.apache.jasper.compiler.TldLocationsCache.level = FINE
# To see debug messages for HTTP/2 handling, uncomment the following line:
#org.apache.coyote.http2.level = FINE
# To see debug messages for WebSocket handling, uncomment the following line:
#org.apache.tomcat.websocket.level = FINE
从这里可以看出它实际控制着tomcat 安装目录下/logs里面的五类日志 ：catalina、localhost、manager、admin、host-manager 。
另外，tomcat 的日志等级有：日志输出级别：SEVERE (最高级别) > WARNING > INFO > CONFIG > FINE > FINER(精心) > FINEST (所有内容,最低级别),使用日志输出级别越高那么tomcat对内存的消耗就越低，但是具体的级别选择需要根据你自己的情况来定。
将日志清理后， 同时调整日志级别， 系统恢复正常运行。
总结:
测试是一门技术, 更是一门艺术. 也许你今天拥有的技术, 明天就会被淘汰. 同时需要我们开拓思维和眼界, 积极拥抱变化, 学习新知识, 新方法,新技能, 计算机领域讲究的是实践, 学习更要讲究方式方法. 学习和动手一定要结合, 光看不练,犹如看武功秘籍, 是永远成不了武功大侠的.
