配置文件详解

[Journal]
#Storage=persistent
Storage=persistent
#Compress=yes
#Seal=yes
#SplitMode=uid
#SyncIntervalSec=5m
#RateLimitInterval=30s
#RateLimitBurst=1000
#SystemMaxUse=
#SystemKeepFree=
#SystemMaxFileSize=
#RuntimeMaxUse=
#RuntimeKeepFree=
#RuntimeMaxFileSize=
#MaxRetentionSec=
#MaxFileSec=1month
ForwardToSyslog=yes
ForwardToKMsg=no
ForwardToConsole=no
#ForwardToWall=yes
#TTYPath=/dev/console
MaxLevelStore=debug
MaxLevelSyslog=debug
MaxLevelKMsg=notice
MaxLevelConsole=info
#MaxLevelWall=emerg

SplitMode:Controls whether to split up journal files per user. One of "uid", "login" and "none". If "uid", all users will get each their own journal
           files regardless of whether they possess a login session or not, however system users will log into the system journal. If "login", actually
           logged-in users will get each their own journal files, but users without login session and system users will log into the system journal. If
           "none", journal files are not split up by user and all messages are instead stored in the single system journal. Note that splitting up journal
           files by user is only available for journals stored persistently. If journals are stored on volatile storage (see above), only a single journal
           file for all user IDs is kept. Defaults to "uid".

Seal:默认开启，保护journal file日志文件不会被篡改，sealing key可以通过：journalctl(1)'s --setup-keys命令获得，Forward Secure Sealing (FSS) for all persistent journal files is enabled.

SYSLOG(3)

Journal Export Format

Note that this document describes the binary serialization format of journals only, as used for transfer across the network. For interfacing with web technologies there's the Journal JSON Format. The binary format on disk is documented as Journal File Format. Before reading on, please make sure you are aware of the basic properties of journal entries, in particular realize that they may include binary non-text data (though usually don't), and the same field might have multiple values assigned within the same entry (though usually hasn't).

这么看journal有几种格式：

  • ‘binary serialization format’，also 'Journal Export Format',used for transfer across the network
  • 'Journal JSON Format',For interfacing with web technologies
  • 'binary format ',he binary format on disk is documented as Journal File Format

systemd-journald行为方式

lsof -p $(pidof /usr/lib/systemd/systemd-journald)

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#cat /etc/systemd/journald.conf
[Journal]
Storage=persistent
#Compress=yes
#Seal=yes
#SplitMode=uid
#SyncIntervalSec=5m
#RateLimitInterval=30s
#RateLimitBurst=1000
#SystemMaxUse=
#SystemKeepFree=
SystemMaxFileSize=8M
SystemMaxFiles=4
#RuntimeMaxUse=
#RuntimeKeepFree=
#RuntimeMaxFileSize=
#MaxRetentionSec=
#MaxFileSec=1month
ForwardToSyslog=yes
ForwardToKMsg=no
ForwardToConsole=no
#ForwardToWall=yes
#TTYPath=/dev/console
MaxLevelStore=debug
MaxLevelSyslog=debug
MaxLevelKMsg=notice
MaxLevelConsole=info
#MaxLevelWall=emerg

SystemMaxFiles 参数貌似没有起到作用！！！

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#ll
total 180280
-rw-r-----  1 root root 8388608 Sep 13 17:23 system@95b85109e44b4ea89ce66e094c94279b-0000000000004e88-00053c5ff5809def.journal
-rw-r-----  1 root root 8388608 Sep 13 17:25 system@95b85109e44b4ea89ce66e094c94279b-0000000000006e68-00053c602bb61502.journal
-rw-r-----  1 root root 8388608 Sep 13 17:27 system@95b85109e44b4ea89ce66e094c94279b-0000000000009f12-00053c60322d04c3.journal
-rw-r-----  1 root root 8388608 Sep 13 17:29 system@95b85109e44b4ea89ce66e094c94279b-000000000000cb31-00053c6038479d6c.journal
-rw-r-----  1 root root 8388608 Sep 13 17:29 system@95b85109e44b4ea89ce66e094c94279b-000000000000f4be-00053c603ebe24f1.journal
-rw-r-----  1 root root 8388608 Sep 13 17:30 system@95b85109e44b4ea89ce66e094c94279b-000000000001160d-00053c6041a0db53.journal
-rw-r-----  1 root root 8388608 Sep 13 17:31 system@95b85109e44b4ea89ce66e094c94279b-0000000000013963-00053c6045174c27.journal
-rw-r-----  1 root root 8388608 Sep 13 17:32 system@95b85109e44b4ea89ce66e094c94279b-00000000000158cf-00053c604839c78f.journal
-rw-r-----  1 root root 8388608 Sep 13 17:33 system@95b85109e44b4ea89ce66e094c94279b-0000000000016f16-00053c6049a0781f.journal
-rw-r-----  1 root root 8388608 Sep 13 17:33 system@95b85109e44b4ea89ce66e094c94279b-0000000000019a25-00053c604e8e6c3e.journal
-rw-r-----  1 root root 8388608 Sep 13 17:35 system@95b85109e44b4ea89ce66e094c94279b-000000000001a953-00053c604eca2bf0.journal
-rw-r-----  1 root root 8388608 Sep 13 17:37 system@95b85109e44b4ea89ce66e094c94279b-000000000001d162-00053c6054d3d62b.journal
-rw-r-----  1 root root 8388608 Sep 13 17:39 system@95b85109e44b4ea89ce66e094c94279b-000000000001fb55-00053c605bd49733.journal
-rw-r-----  1 root root 8388608 Sep 13 17:40 system.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:23 user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000004ef3-00053c5ffc035f5e.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:29 user-120063@eca90592d5664b05b2105e0c4e422d85-000000000000d096-00053c60386fd583.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:30 user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000012a78-00053c60434097e3.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:33 user-120063@eca90592d5664b05b2105e0c4e422d85-00000000000176ad-00053c604a4e7164.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:39 user-120063@eca90592d5664b05b2105e0c4e422d85-000000000001fda6-00053c605c2d0517.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:40 user-120063.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:23 user-122575@a0ae95f91a2f430d8869228a5c1d142f-0000000000004eb3-00053c5ff957f41a.journal
-rw-r-----+ 1 root root 8388608 Sep 13 17:40 user-122575.journal

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#du -sh *
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000004e88-00053c5ff5809def.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000006e68-00053c602bb61502.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000009f12-00053c60322d04c3.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000000cb31-00053c6038479d6c.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000000f4be-00053c603ebe24f1.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001160d-00053c6041a0db53.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000013963-00053c6045174c27.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-00000000000158cf-00053c604839c78f.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000016f16-00053c6049a0781f.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000019a25-00053c604e8e6c3e.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001a953-00053c604eca2bf0.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001d162-00053c6054d3d62b.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001fb55-00053c605bd49733.journal
8.1M    system.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000004ef3-00053c5ffc035f5e.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000000d096-00053c60386fd583.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000012a78-00053c60434097e3.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-00000000000176ad-00053c604a4e7164.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000001fda6-00053c605c2d0517.journal
8.0M    user-120063.journal
8.0M    user-122575@a0ae95f91a2f430d8869228a5c1d142f-0000000000004eb3-00053c5ff957f41a.journal
8.0M    user-122575.journal

前面SystemMaxFileSize=8M，

现在修改为如下：

SystemMaxFileSize=20M，然后执行：systemctl daemon-reload;systemctl restart systemd-journald;

继续狂打日志：for i in seq 1 20000;do logger -p authpriv.info hello$i;done

按照我的猜想，后面的文件最大，应该只有20M左右了吧，于是开始打日志，打了一会儿，发现还是8M，多打一会儿日志后，后面滚动的文件大小确实差不多是20M了，看来不是立即生效，很让人费解；

如下，你可以看到滚动后产生的靠近20M的文件了，但是，还是不知道究竟什么时候开始删除之前的文件；究竟可以保存多少个文件？？？

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#du -sh *
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000004e88-00053c5ff5809def.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000006e68-00053c602bb61502.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000009f12-00053c60322d04c3.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000000cb31-00053c6038479d6c.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000000f4be-00053c603ebe24f1.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001160d-00053c6041a0db53.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000013963-00053c6045174c27.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-00000000000158cf-00053c604839c78f.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000016f16-00053c6049a0781f.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000019a25-00053c604e8e6c3e.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001a953-00053c604eca2bf0.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001d162-00053c6054d3d62b.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-000000000001fb55-00053c605bd49733.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000022537-00053c6062d58196.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000024f10-00053c6069d64213.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-00000000000278e2-00053c6070d787d1.journal
17M     system@95b85109e44b4ea89ce66e094c94279b-000000000002a1a4-00053c607a097db8.journal
8.0M    system.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000004ef3-00053c5ffc035f5e.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000000d096-00053c60386fd583.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000012a78-00053c60434097e3.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-00000000000176ad-00053c604a4e7164.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000001fda6-00053c605c2d0517.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000024151-00053c60674ac34c.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000026981-00053c606e1343f0.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000002a927-00053c607ff1def4.journal
8.0M    user-120063.journal
8.0M    user-122575@a0ae95f91a2f430d8869228a5c1d142f-0000000000004eb3-00053c5ff957f41a.journal
8.0M    user-122575.journal

另外发现，之前将journal文件改为persistent后，/run/log/journal/613fd1717b844226af5ea83f4849d6dd目录下的文件的数量并没有随即自动删除。

root@srmbuffer010242252156.cloud.dg /run/log/journal/613fd1717b844226af5ea83f4849d6dd]
#systemctl status systemd-journald
● systemd-journald.service - Journal Service
   Loaded: loaded (/usr/lib/systemd/system/systemd-journald.service; static; vendor preset: disabled)
   Active: active (running) since Tue 2016-09-13 17:47:23 CST; 12min ago
     Docs: man:systemd-journald.service(8)
           man:journald.conf(5)
 Main PID: 53736 (systemd-journal)
   Status: "Processing requests..."
   CGroup: /system.slice/systemd-journald.service
           └─53736 /usr/lib/systemd/systemd-journald

Sep 13 17:47:23 srmbuffer010242252156.cloud.dg systemd-journal[53736]: Permanent journal is using 216.0M (max allowed 4.0G, trying to leave 4.0G free…t 4.0G).
Sep 13 17:47:23 srmbuffer010242252156.cloud.dg systemd-journal[53736]: Journal started

当前可以发现，现在已经使用了216.0M ，但是最多可以使用4.0G；

于是，我们修改：

SystemMaxUse=100M

看看什么报错：

#systemctl daemon-reload;
#systemctl restart systemd-journald
[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#systemctl status systemd-journald
● systemd-journald.service - Journal Service
   Loaded: loaded (/usr/lib/systemd/system/systemd-journald.service; static; vendor preset: disabled)
   Active: active (running) since Tue 2016-09-13 18:02:15 CST; 6s ago
     Docs: man:systemd-journald.service(8)
           man:journald.conf(5)
 Main PID: 5270 (systemd-journal)
   Status: "Processing requests..."
   CGroup: /system.slice/systemd-journald.service
           └─5270 /usr/lib/systemd/systemd-journald

Sep 13 18:02:15 srmbuffer010242252156.cloud.dg systemd-journal[5270]: Permanent journal is using 264.0M (max allowed 100.0M, trying to leave 4.0G fre…264.0M).
Sep 13 18:02:15 srmbuffer010242252156.cloud.dg systemd-journal[5270]: Journal started

结果，发现没有什么报错，反而是/var/log/journal/目录下的，老旧的文件被删除了；

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#du -sh *
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000022537-00053c6062d58196.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-0000000000024f10-00053c6069d64213.journal
8.1M    system@95b85109e44b4ea89ce66e094c94279b-00000000000278e2-00053c6070d787d1.journal
17M     system@95b85109e44b4ea89ce66e094c94279b-000000000002a1a4-00053c607a097db8.journal
17M     system@95b85109e44b4ea89ce66e094c94279b-000000000002c796-00053c608966f4f5.journal
8.1M    system.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000001fda6-00053c605c2d0517.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000024151-00053c60674ac34c.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-0000000000026981-00053c606e1343f0.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000002a927-00053c607ff1def4.journal
8.0M    user-120063@eca90592d5664b05b2105e0c4e422d85-000000000002c9a0-00053c608b0fc119.journal
8.0M    user-120063.journal
8.0M    user-122575.journal

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#du -sh /var/log/journal/613fd1717b844226af5ea83f4849d6dd
121M    /var/log/journal/613fd1717b844226af5ea83f4849d6dd

按照这个逻辑，我继续写大量日志，应该找个目录大小不会增加了吧。只会删除老旧文件：

测试一下：

[root@srmbuffer010242252156.cloud.dg /var/log/journal/613fd1717b844226af5ea83f4849d6dd]
#for i in `seq 1 20000`;do logger -p authpriv.info test$i;done
Sep 13 18:41:35 srmbuffer010242252156.cloud.dg systemd-journal[5270]: Suppressed 18998 messages from /user.slice/user-122575.slice

哟呵，日志被抑制了；不过，看来，日志文件有多少个，是根据总的可用空间决定；比如：我们只有SystemMaxUse=100M可用空间，SystemMaxFileSize=20M设置单个journal文件大小只有20的话，那基本上只会保存5个历史文件左右；

systemd-journald详解的更多相关文章

  1. systemd服务详解-技术流ken

    简介 在centos5中生成和管理用户空间中的进程以及完成系统的初始化使用的是init,并且是依次启动.在centos6中则是使用的upstart,在一定程度上实现了并行启动,但是仍然存在依赖关系,到 ...

  2. CentOS7进程管理systemd详解

      概述: 系统启动过程中,当内核启动完成,后加载根文件系统,后就绪的一些用户空间的服务的管理工作,就交由init进行启动和管理,在CentOS6之前的init的管理方式都类似,相关的内容我们在之前的 ...

  3. centos7上systemd详解

    centos7上systemd详解  发表于 2016-06-07 |  分类于 linux CentOS 7继承了RHEL 7的新的特性,例如强大的systemd, 而systemd的使用也使得以往 ...

  4. cetos7 systemd 详解

      CentOS7/RHEL7 systemd详解 目录1. 为什么是systemd(1) 关于Linux服务管理(2) SysV init的优缺点(3) UpStart的改进(4) systemd的 ...

  5. systemd详解

    CentOS 7 使用systemd替换了SysV.Systemd目的是要取代Unix时代以来一直在使用的init系统,兼容SysV和LSB的启动脚本,而且够在进程启动过程中更有效地引导加载服务. s ...

  6. CentOS 7 中 Systemd详解

    一.systemd的由来 Linux一直以来采用init进程但是init有两个缺点: 1.启动时间长.Init进程是串行启动,只有前一个进程启动完,才会启动下一个进程.(这也是CentOS5的主要特征 ...

  7. linux systemd详解

    CentOS 7 使用systemd替换了SysV.Systemd目的是要取代Unix时代以来一直在使用的init系统,兼容SysV和LSB的启动脚本,而且够在进程启动过程中更有效地引导加载服务. s ...

  8. docker入门级详解

    Docker 1 docker安装 yum install docker [root@topcheer ~]# systemctl start docker [root@topcheer ~]# mk ...

  9. [转帖]持久化journalctl日志清空命令查看配置参数详解

    持久化journalctl日志清空命令查看配置参数详解 最近 linux上面部署服务 习惯使用systemd 进行处理 这样最大的好处能够 使用journalctl 进行查看日志信息. 今天清理了下 ...

随机推荐

  1. C# - 创建List属性的简单方法

    不用担心List没有创建问题. private ObservableCollection<EquipmentItem> _optionalCollection; public Observ ...

  2. php中strstr、strrchr、substr、stristr四个函数的区别总结

    php中strstr.strrchr.substr.stristr四个函数的区别总结 投稿:junjie 字体:[增加 减小] 类型:转载 时间:2014-09-22我要评论 这篇文章主要介绍了php ...

  3. cocos2d-x核心基础类

    Application 应用程序入口类 EGLView 绘图句柄 Director Node Layer Scene

  4. laravel3中文文档是迈入laravel4的捷径

    http://v3.golaravel.com/docs/ 目录 Laravel概览 更新日志 安装与设置 系统需求 安装 服务器设置 基本设置 环境 友好的链接(URL) 路由 基础 通配符(Wil ...

  5. Android Fragment详解(三)： 实现Fragment的界面

    为fragment添加用户界面: Fragment一般作为activity的用户界面的一部分,把它自己的layout嵌入到activity的layout中. 一个 要为fragment提供layout ...

  6. 绘制更Smooth的UI

    以前很长一段时间,在自定义控制绘制时,只是简单的定义一个QPainter对象而开始绘画.经常会画一些圆角矩形,甚至是一些不规则的图形.对于不规则的图形来说,如果PS技术不好,或者mask制作的不好,常 ...

  7. LoadRuner性能测试之内存分析方法及步骤（Windows）

    1.首先观察Available  Mbytes(可用内存),至少要>=1/2的内存空间 2.然后观察Pages/sec值是不是很大 3.再观察Page  Faules/sec是不是很大,其值表示 ...

  8. Enabling Active Directory Authentication for VMWare Server running on Linux《转载》

    Enabling Active Directory Authentication for VMWare Server running on Linux Version 0.2 - Adam Breid ...

  9. 当chm文档点击左侧，右侧无内容时的解决方案

    右击chm文件->属性->安全选项卡,选择你登陆计算机的用户名,把权限改成完全控制就可以显示了

  10. (转).net控件dropdownlist动态绑定数据

    DropDownList控件的使用(数据绑定)(.net学习笔记二)(2006-10-12 07:28:49) 转载   分类:.net学习笔记 一.在页面初始化时候将集合绑定到DropDownLis ...