如何查询Linux服务的作用

服务列表好办，chkconfig --list 就有了，但是他们都是做什么用的，系统中是否用得到，怎么查？

1、man 服务名

最广泛使用的查询方式man

比如

# man abrtd

ABRTD(8)                          ABRT Manual                        ABRTD(8)

NAME

      abrtd - automated bug reporting tool麓s daemon.

SYNOPSIS

      abrtd [-dsv[v]...]

DESCRIPTION

      abrtd is a daemon that watches for application crashes. When a crash

      occurs, it collects the problem data (core file, application鈥檚 command

      line etc.) and takes action according to the type of application that

      crashed and according to the configuration in the abrt.conf config

      file. There are plugins for various actions: for example to report the

      crash to Bugzilla, to mail the report, or to transfer the report via

      FTP or SCP. See the manual pages for the respective plugins.

2、rpm -qi

当然，也会有一些服务通过man查询不到， 比如 blk-availability 、 abrt-ccpp。

我们可以通过启动脚本对应的rpm包来查询，知道这个rpm包的作用，也就知道这个服务的作用了。

rpm -qi `rpm -qf /etc/rc.d/init.d/服务名` # 注意是反引号

看Description部分，一般就是这个rpm包的作用了，至少能看出来和哪些功能相关。

[root@localhost ~]# rpm -qi `rpm -qf /etc/rc.d/init.d/blk-availability`

Name        : lvm2                        Relocations: (not relocatable)

Version    : 2.02.98                          Vendor: CentOS

Release    : 9.el6                        Build Date: Fri 22 Feb 2013 02:21:40 PM CST

Install Date: Wed 19 Mar 2014 05:06:26 PM CST      Build Host: c6b8.bsys.dev.centos.org

Group      : System Environment/Base      Source RPM: lvm2-2.02.98-9.el6.src.rpm

Size        : 1417702                          License: GPLv2

Signature  : RSA/SHA1, Sun 24 Feb 2013 01:39:56 AM CST, Key ID 0946fca2c105b9de

Packager    : CentOS BuildSystem <http://bugs.centos.org>

URL        : http://sources.redhat.com/lvm2

Summary    : Userland logical volume management tools

Description :

LVM2 includes all of the support for handling read/write operations on

physical volumes (hard disks, RAID-Systems, magneto optical, etc.,

multiple devices (MD), see mdadd(8) or even loop devices, see

losetup(8)), creating volume groups (kind of virtual disks) from one

or more physical volumes and creating one or more logical volumes

(kind of logical partitions) in volume groups.