centos 7 升級后yum install出現Exiting on user cancel

centos 7.x升級后用yum install進行安裝時經常出現Exiting on user cancel，例如：

[root@localhost ~]# yum install logstash
Loaded plugins: axelget, fastestmirror
No metadata available for base
No metadata available for docker-main-repo
No metadata available for epel
No metadata available for extras
No metadata available for logstash-1.5
No metadata available for updates
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * epel: mirrors.ustc.edu.cn
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
Resolving Dependencies
--> Running transaction check
---> Package logstash.noarch 1:1.5.6-1 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=========================================================================================================================================================================================================
 Package                                        Arch                                         Version                                            Repository                                          Size
=========================================================================================================================================================================================================
Installing:
 logstash                                       noarch                                       1:1.5.6-1                                          logstash-1.5                                        86 M

Transaction Summary
=========================================================================================================================================================================================================
Install  1 Package

Total download size: 86 M
Installed size: 133 M
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
logstash-1.5.6-1.noarch.rpm                                                                                                                                                       |    0 B  00:00:30 ... 
logstash-1.5.6-1.noarch.rpm                                                            2% [==                                                                          ] 141 kB/s | 2.5 MB  00:10:09 ETA 

Exiting on user cancel

總是出現Exiting on user cancel，導致不能正常安裝。

這是yum的一個bug導致的問題。修改/usr/lib/python2.7/site-packages/urlgrabber/grabber.py.

vi /usr/lib/python2.7/site-packages/urlgrabber/grabber.py

將第1510行和1517行注釋掉即可
修改前：

1510             elif errcode == 42:
1511                 # this is probably wrong but ultimately this is what happens
1512                 # we have a legit http code and a pycurl 'writer failed' code
1513                 # which almost always means something aborted it from outside
1514                 # since we cannot know what it is -I'm banking on it being
1515                 # a ctrl-c. XXXX - if there's a way of going back two raises to
1516                 # figure out what aborted the pycurl process FIXME
1517                 raise KeyboardInterrupt

修改后：

1510             #elif errcode == 42:
1511                 # this is probably wrong but ultimately this is what happens
1512                 # we have a legit http code and a pycurl 'writer failed' code
1513                 # which almost always means something aborted it from outside
1514                 # since we cannot know what it is -I'm banking on it being
1515                 # a ctrl-c. XXXX - if there's a way of going back two raises to
1516                 # figure out what aborted the pycurl process FIXME
1517             #    raise KeyboardInterrupt

然后以root用戶運行如下命令升級：

yum clean metadata
yum clean all
yum upgrade

升級完成后運行yum命令安裝即可。

• 參考文檔：http://www.ostechnix.com/yum-dont-work-in-clean-centos-7-how-to-fix-it/