在Linux上我们少不了安装软件，在centos7中有两种方法rpm与yum安装方式。但在我们用rpm安装过程中你会发现，我们往往装个软件命令行要写的很长，要写那个包的完整路径。有时候还要解决包的依赖问题，那么有没有一种短一点的呢？
那就是我们配yum源来安装，基本用yum install {rpmfile}就可以安装，不仅方便还解决了包之间的依赖问题。那么最大的问题就是创建yum仓库。
下面我们搭建一个属于自己的ftp（yum源）仓库：
1.我们要准备光盘(centos 6 准备6的光盘，centos7准备7的光盘）；
2.安装ftp所需的程序包vsftpd，默认没安装
[root@centos7 ~]#rpm -qi vsftp
package vsftp is not installed 注：通过查询没有安装
[root@centos7 ~]#rpm -ivh /misc/cd/Packages/vsftpd-3.0.2-21.el7.x86_64.rpm 注：安装vsftpd包
warning: /misc/cd/Packages/vsftpd-3.0.2-21.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEY
Preparing... ################################# [100%]
Updating / installing...
1:vsftpd-3.0.2-21.el7 ################################# [100%]
[root@centos7 ~]#rpm -qi vsftpd 安装成功显示详细信息
Name : vsftpd
Version : 3.0.2
Release : 21.el7
Architecture: x86_64
Install Date: Tue 13 Jun 2017 09:51:15 PM +10
Group : System Environment/Daemons
Size : 356228
.......
vsftpd is a Very Secure FTP daemon. It was written completely from
scratch.
3.启动ftp服务：
[root@centos7 ~]#netstat -ntl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN
tcp 0 0 192.168.122.1:53 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp6 0 0 :::111 :::* LISTEN
tcp6 0 0 :::22 :::* LISTEN
tcp6 0 0 ::1:631 :::* LISTEN
tcp6 0 0 ::1:25 :::* LISTEN
[root@centos7 ~]#systemctl start vsftpd 注：启动ftp服务
[root@centos7 ~]#netstat -ntl 注：打开了21端口
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN
tcp 0 0 192.168.122.1:53 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp6 0 0 :::111 :::* LISTEN
tcp6 0 0 :::21 :::* LISTEN
tcp6 0 0 :::22 :::* LISTEN
tcp6 0 0 ::1:631 :::* LISTEN
tcp6 0 0 ::1:25 :::* LISTEN
这个启动只是相对暂时的，等到下次再启动Linux就失效了，因此我们可以设置开机启动
[root@centos7 ~]#systemctl enable vsftpd
Created symlink from /etc/systemd/system/multi-user.target.wants/vsftpd.service to /usr/lib/systemd/system/vsftpd.service.
注：在centos上安装方式一样，但启动有点不一样：
[root@centos6 ~]#service vsftpd start 注：启动服务打开21端口
Starting vsftpd for vsftpd: [ OK ]
[root@centos6 ~]#chkconfig vsftpd on注：开机启动
现在我们可以看到有了这个文件夹
[root@centos7 ~]#cd /var/ftp
[root@centos7 ftp]#ls
pub
[root@centos7 pub]#touch hello.txt 注：在ftp/pub下创建一个文件
[root@centos7 pub]#cat >hello.txt
hello world!
[root@centos7 pub]#ls
hello.txt
我们可以通过ifconfig来查询IP通过IP访问下,我们会发现我们并不能打开它！
[root@centos7 ~]#ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.18.138 netmask 255.255.255.0 broadcast 192.168.18.255
......
ens34: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.17.253.83 netmask 255.255.0.0 broadcast 172.17.255.255
这是因为 我们还没有禁用防火墙，默认情况下现在还不能访问！
[root@centos7 ~]#iptables -nvL 注：查询防火墙（目前是开启状态）
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
0 0 ACCEPT udp -- virbr0 * 0.0.0.0/0 0.0.0.0/0 udp dpt:53
0 0 ACCEPT tcp -- virbr0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:53
0 0 ACCEPT udp -- virbr0 * 0.0.0.0/0 0.0.0.0/0 udp dpt:67
0 0 ACCEPT tcp -- virbr0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:67
99841 304M ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED
0 0 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0
5150 708K INPUT_direct all -- * * 0.0.0.0/0 0.0.0.0/0
5150 708K INPUT_ZONES_SOURCE all -- * * 0.0.0.0/0 0.0.0.0/0
5150 708K INPUT_ZONES all -- * * 0.0.0.0/0 0.0.0.0/0
0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 ctstate INVALID
5147 708K REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited
Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
0 0 ACCEPT all -- * virbr0 0.0.0.0/0 192.168.122.0/24 ctstate RELATED,ESTABLISHED
0 0 ACCEPT all -- virbr0 * 192.168.122.0/24 0.0.0.0/0
0 0 ACCEPT all -- virbr0 virbr0 0.0.0.0/0 0.0.0.0/0
0 0 REJECT all -- * virbr0 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable
0 0 REJECT all -- virbr0 * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable
........
pkts bytes target prot opt in out source destination
Chain IN_public_log (1 references)
pkts bytes target prot opt in out source destination
Chain OUTPUT_direct (1 references)
pkts bytes target prot opt in out source destination
[root@centos7 ~]#systemctl stop firewalld.service 注：关闭防护墙
[root@centos7 ~]#iptables -nvL 注：现已关闭
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
[root@centos7 ~]#systemctl disable firewalld.service 注：默认情况下开机启动了防火墙，如果下次还继续用，可暂时开启开机禁用防火墙。
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
Removed symlink /etc/systemd/system/basic.target.wants/firewalld.service.
然后我们在进行访问ftp
就可以访问了......
4.在pub下创建yum仓库并从光盘拷贝
[root@centos7 pub]#cd /var/ftp/pub
[root@centos7 pub]#mkdir centos7
[root@centos7 pub]#ls
centos7
[root@centos7 pub]#cp -ar /misc/cd/* centos7
[root@centos7 pub]#cd centos7/
[root@centos7 centos7]#ls
CentOS_BuildTag EULA images LiveOS repodata RPM-GPG-KEY-CentOS-Testing-7
EFI GPL isolinux Packages RPM-GPG-KEY-CentOS-7 TRANS.TBL
现在我们已经拷贝完毕！可以配置yum的[name].repo文件
[root@centos7 pub]#cd /etc/yum.repos.d/
[root@centos7 yum.repos.d]#ls 注：这是原有的repo配置文件
CentOS-Base.repo CentOS-Debuginfo.repo CentOS-Media.repo CentOS-Vault.repo
CentOS-CR.repo CentOS-fasttrack.repo CentOS-Sources.repo
[root@centos7 yum.repos.d]#mkdir backup
[root@centos7 yum.repos.d]#mv *.repo backup 注：我们可以把原有的repo文件移动到创建的backup目录下
[root@centos7 yum.repos.d]#ls
backup
[root@centos7 yum.repos.d]#vim base.repo 注：创建新的repo文件
[root@centos7 yum.repos.d]#cat base.repo
[base]
name=centos 7
baseurl=ftp://192.168.18.138/pub/centos7/
gpgcheck=0
现在我们就可以正常访问ftp了，也可以用自己搭建的yum源安装软件
[root@centos7 ~]#yum install tree
Loaded plugins: fastestmirror, refresh-packagekit, security
.........
--> Running transaction check
---> Package tree.x86_64 0:1.6.0-10.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
==============================================================================================================
Package Arch Version Repository Size
==============================================================================================================
Installing:
tree x86_64 1.6.0-10.el7 base 46 k
Transaction Summary
============================================
......
如有不足请多多指教。
