本文为转载：原文出处：https://www.cnblogs.com/saolv/p/6963314.html
centos下安装pip时失败：
[root@wfm ~]# yum -y install pip
Loaded plugins: fastestmirror, refresh-packagekit, security
Loading mirror speeds from cached hostfile
* base: mirrors.tuna.tsinghua.edu.cn
* extras: mirrors.tuna.tsinghua.edu.cn
* updates: mirrors.tuna.tsinghua.edu.cn
Setting up Install Process
No package pip available.
Error: Nothing to do
解决方法：
需要先安装扩展源EPEL。
EPEL(http://fedoraproject.org/wiki/EPEL) 是由 Fedora 社区打造，为 RHEL 及衍生发行版如 CentOS、Scientific Linux 等提供高质量软件包的项目。
首先安装epel扩展源：
sudo yum -y install epel-release
然后再安装pip
~]# sudo yum -y install python-pip
Loaded plugins: fastestmirror, refresh-packagekit, security
Loading mirror speeds from cached hostfile
epel/metalink | 4.9 kB 00:00
* base: mirrors.tuna.tsinghua.edu.cn
* epel: mirrors.neusoft.edu.cn
* extras: mirrors.tuna.tsinghua.edu.cn
* updates: mirrors.tuna.tsinghua.edu.cn
epel | 4.3 kB 00:00
epel/primary_db | 5.8 MB 00:07
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package python-pip.noarch 0:7.1.0-1.el6 will be installed
--> Processing Dependency: python-setuptools for package: python-pip-7.1.0-1.el6.noarch
--> Running transaction check
---> Package python-setuptools.noarch 0:0.6.10-3.el6 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
================================================================
Package Arch Version Repository
Size
================================================================
Installing:
python-pip noarch 7.1.0-1.el6 epel 1.5 M
Installing for dependencies:
python-setuptools noarch 0.6.10-3.el6 base 336 k
Transaction Summary
================================================================
Install 2 Package(s)
Total download size: 1.9 M
Installed size: 8.1 M
Downloading Packages:
(1/2): python-pip-7.1.0-1.el6.noarch.rpm | 1.5 MB 00:01
(2/2): python-setuptools-0.6.10-3.el6.no | 336 kB 00:00
----------------------------------------------------------------
Total 755 kB/s | 1.9 MB 00:02
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID 0608b895: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
Importing GPG key 0x0608B895:
Userid : EPEL (6) <epel@fedoraproject.org>
Package: epel-release-6-8.noarch (@extras)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : python-setuptools-0.6.10-3.el6.noarch 1/2
Installing : python-pip-7.1.0-1.el6.noarch 2/2
Verifying : python-pip-7.1.0-1.el6.noarch 1/2
Verifying : python-setuptools-0.6.10-3.el6.noarch 2/2
Installed:
python-pip.noarch 0:7.1.0-1.el6
Dependency Installed:
python-setuptools.noarch 0:0.6.10-3.el6
Complete!
OK 成功！