小文的个人博客|首页

[[ slider_text ]]

[[ item.c]]

Linux知识点七

发布时间: 2022-05-12 作者: 小文来源: 小文的个人博客

Linux

## 1.守护进程（ Daemon ）

始终在后台运行并响应合法请求的程序称为守护（Daemon）进程。

## 2.使用systemctl管理服务

```Bash
显示当前已运行的所有服务
systemctl --type service 或
systemctl -t service

启动名为ServiceName的服务
systemctl start <ServiceName>
停止名为ServiceName的服务
systemctl stop <ServiceName>
重启名为ServiceName的服务
systemctl restart <ServiceName>
重新加载名为ServiceName服务的配置文件
systemctl reload <ServiceName>
查看名为ServiceName服务的状态信息
systemctl status <ServiceName>

在启动系统时启用名为ServiceName的服务
systemctl enable <ServiceName>
在启动系统时停用名为ServiceName的服务
systemctl disable <ServiceName>
查看名为ServiceName的服务是否在启动系统时启用
systemctl is-enabled <ServiceName>
查看所有服务是否在启动系统时启用
systemctl list-unit-files -t service

```

## 3.自动安排进程任务

atd：at和batch命令的守护进程

at  安排作业在某一时刻执行一次
batch  安排作业在系统负载不重时执行一次

crond：Cron服务的守护进程，该程序周期地运行用户调度的任务

corn 安排周期性运行的作业

## 4./etc/rsyslog.conf 的规则

规则由 selector 和 action 两部分组成

每一行的格式为:

facility.priority        action

设备.级别        动作

```Bash
[root@VM-24-11-centos etc]# cat /etc/rsyslog.conf |more
# rsyslog configuration file

# For more information see /usr/share/doc/rsyslog-*/rsyslog_conf.html
# If you experience problems, see http://www.rsyslog.com/doc/troubleshoot.html

#### MODULES ####

# The imjournal module bellow is now used as a message source instead of imuxsock.
$ModLoad imuxsock # provides support for local system logging (e.g. via logger command)
$ModLoad imjournal # provides access to the systemd journal
#$ModLoad imklog # reads kernel messages (the same are read from journald)
#$ModLoad immark  # provides --MARK-- message capability

# Provides UDP syslog reception
#$ModLoad imudp
#$UDPServerRun 514

# Provides TCP syslog reception
#$ModLoad imtcp
#$InputTCPServerRun 514

#### GLOBAL DIRECTIVES ####

# Where to place auxiliary files
$WorkDirectory /var/lib/rsyslog

# Use default timestamp format
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat

# File syncing capability is disabled by default. This feature is usually not required,
# not useful and an extreme performance hit
#$ActionFileEnableSync on

# Include all config files in /etc/rsyslog.d/
$IncludeConfig /etc/rsyslog.d/*.conf

# Turn off message reception via local log socket;
# local messages are retrieved through imjournal now.
$OmitLocalLogging on

# File to store the position in the journal
$IMJournalStateFile imjournal.state

#### RULES ####

# Log all kernel messages to the console.
# Logging much else clutters up the screen.
#kern.*                                                 /dev/console

# Log anything (except mail) of level info or higher.
# Don't log private authentication messages!
*.info;mail.none;authpriv.none;cron.none                /var/log/messages

# The authpriv file has restricted access.
authpriv.*                                              /var/log/secure

# Log all the mail messages in one place.
mail.*                                                  -/var/log/maillog

# Log cron stuff
cron.*                                                  /var/log/cron

# Everybody gets emergency messages
*.emerg                                                 :omusrmsg:*

# Save news errors of level crit and higher in a special file.
uucp,news.crit                                          /var/log/spooler

# Save boot messages also to boot.log
local7.*                                                /var/log/boot.log

# ### begin forwarding rule ###
# The statement between the begin ... end define a SINGLE forwarding
# rule. They belong together, do NOT split them. If you create multiple
# forwarding rules, duplicate the whole block!
# Remote Logging (we use TCP for reliable delivery)
#
# An on-disk queue is created for this action. If the remote host is
# down, messages are spooled to disk and sent when it is up again.
#$ActionQueueFileName fwdRule1 # unique name prefix for spool files
#$ActionQueueMaxDiskSpace 1g   # 1gb space limit (use as much as possible)
#$ActionQueueSaveOnShutdown on # save messages to disk on shutdown
#$ActionQueueType LinkedList   # run asynchronously
#$ActionResumeRetryCount -1    # infinite retries if host is down
# remote host is: name/ip:port, e.g. 192.168.0.1:514, port optional
#*.* @@remote-host:514
# ### end of the forwarding rule ###
```

## 5.目标动作

rsyslog使用 udp:514 端口传送日志信息

## 6.主要日志文件简介

日志保存位置
默认位于：/var/log 目录下
主要日志文件介绍
内核及常规消息日志：/var/log/messages
计划任务日志：/var/log/cron
系统引导日志：/var/log/dmesg

上一篇:Linux知识点六下一篇:Linux知识点八

你觉得文章怎么样