新CentOS配制使用时会遇到的问题，Yum的使用，Yum源切换

su权限问题

# root身份
su
Password: 
su: Authentication failure
sudo passwd root

# 退出root身份
Ctrl + D

配制

查看当前ip，ssh连接

# 查看当前ip （实际为：10.211.55.13）
ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:1c:42:fd:5d:0f brd ff:ff:ff:ff:ff:ff
    inet 10.211.55.13/24 brd 10.211.55.255 scope global dynamic eth0
       valid_lft 1319sec preferred_lft 1319sec
    inet6 fdb2:2c26:f4e4:0:d5a2:332c:f355:9ca0/64 scope global noprefixroute dynamic 
       valid_lft 2591956sec preferred_lft 604756sec
    inet6 fe80::d41a:a6de:73c6:70fd/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN qlen 1000
    link/ether 52:54:00:b9:2f:bb brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN qlen 1000
    link/ether 52:54:00:b9:2f:bb brd ff:ff:ff:ff:ff:ff

切换yum源

更新yum源，进入列表

cd /etc/yum.repos.d/

ls
CentOS-Base.repo CentOS-Debuginfo.repo CentOS-Media.repo CentOS-Vault.repo
CentOS-CR.repo CentOS-fasttrack.repo CentOS-Sources.repo

备份

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak

下载

wget http://mirrors.163.com/.help/CentOS7-Base-163.repo

（或阿里云：wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo）

ls

CentOS7-Base-163.repo CentOS-Debuginfo.repo CentOS-Sources.repo
CentOS-Base.repo._backup CentOS-fasttrack.repo CentOS-Vault.repo
CentOS-CR.repo CentOS-Media.repo

(生成缓存)
yum makecache

更新系统
yum -y update

编译安装前置准备

yum install -y epel-release #扩展包更新包
yum update #更新yum源
yum makecache fast
# 最小化安装时 maybe:
yum -y install wget vim pcre pcre-devel openssl openssl-devel libicu-devel gcc gcc-c++ autoconf libjpeg libjpeg-devel libpng libpng-devel freetype freetype-devel libxml2 libxml2-devel zlib zlib-devel glibc glibc-devel glib2 glib2-devel ncurses ncurses-devel curl curl-devel krb5-devel libidn libidn-devel openldap openldap-devel nss_ldap jemalloc-devel cmake boost-devel bison automake libevent libevent-devel gd gd-devel libtool* libmcrypt libmcrypt-devel mcrypt mhash libxslt libxslt-devel readline readline-devel gmp gmp-devel libcurl libcurl-devel openjpeg-devel