本文操作环境：CentOS7.3系统、php5.4版、Dell G3电脑。
如何解决php5.4 系统升级出错问题？
CentOS7 PHP5.4 升级 PHP5.6 缺少libmcrypt问题解决办法
系统为CentOS7.3，安装PHP后，版本为5.4，当进行升级5.6时发生错误：报错缺少libmcrypt.so.4()(64bit)库
需要安装libmcrypt，libmcrypt-devel：
yum install libmcrypt libmcrypt-devel直接输入以上指令，出错！问题为EPEL源未更新到最新版本。
需要升级EPEL源：
命令：yum -y install epel-release
yum -y install epel-release
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
* base: 100.125.0.40
* extras: 100.125.0.40
* updates: 100.125.0.40
* webtatic: us-east.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package epel-release.noarch 0:7-9 will be updated
---> Package epel-release.noarch 0:7-11 will be an update
--> Finished Dependency Resolution
Dependencies Resolved
========================================================================================================
Package Arch Version Repository Size
========================================================================================================
Updating:
epel-release noarch 7-11 extras 15 k
Transaction Summary
========================================================================================================
Upgrade 1 Package
Total download size: 15 k
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
epel-release-7-11.noarch.rpm | 15 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Updating : epel-release-7-11.noarch 1/2
Cleanup : epel-release-7-9.noarch 2/2
Verifying : epel-release-7-11.noarch 1/2
Verifying : epel-release-7-9.noarch 2/2
Updated:
epel-release.noarch 0:7-11
Complete!从7-9 升级至7-11
EPEL最新是7-12，因此再输入一次上面的指令：
yum -y install epel-release
Loaded plugins: fastestmirror, langpacks
epel/x86_64/metalink | 8.6 kB 00:00:00
epel | 5.4 kB 00:00:00
(1/3): epel/x86_64/updateinfo | 1.0 MB 00:00:00
(2/3): epel/x86_64/group_gz | 90 kB 00:00:01
(3/3): epel/x86_64/primary_db | 6.9 MB 00:01:00
Loading mirror speeds from cached hostfile
* base: 100.125.0.40
* epel: mirrors.aliyun.com
* extras: 100.125.0.40
* updates: 100.125.0.40
* webtatic: uk.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package epel-release.noarch 0:7-11 will be updated
---> Package epel-release.noarch 0:7-12 will be an update
--> Finished Dependency Resolution
Dependencies Resolved
========================================================================================================
Package Arch Version Repository Size
========================================================================================================
Updating:
epel-release noarch 7-12 epel 15 k
Transaction Summary
========================================================================================================
Upgrade 1 Package
Total download size: 15 k
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
epel-release-7-12.noarch.rpm | 15 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Updating : epel-release-7-12.noarch 1/2
Cleanup : epel-release-7-11.noarch 2/2
Verifying : epel-release-7-12.noarch 1/2
Verifying : epel-release-7-11.noarch 2/2
Updated:
epel-release.noarch 0:7-12完成升级7-12。
再次安装
libmcrypt，libmcrypt-devel：
yum install libmcrypt libmcrypt-devel
yum install libmcrypt libmcrypt-devel
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
* base: 100.125.0.40
* epel: my.mirrors.thegigabit.com
* extras: 100.125.0.40
* updates: 100.125.0.40
* webtatic: uk.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package libmcrypt.x86_64 0:2.5.8-13.el7 will be installed
---> Package libmcrypt-devel.x86_64 0:2.5.8-13.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
========================================================================================================
Package Arch Version Repository Size
========================================================================================================
Installing:
libmcrypt x86_64 2.5.8-13.el7 epel 99 k
libmcrypt-devel x86_64 2.5.8-13.el7 epel 13 k
Transaction Summary
========================================================================================================
Install 2 Packages
Total download size: 112 k
Installed size: 302 k
Is this ok [y/d/N]: y
Downloading packages:
(1/2): libmcrypt-2.5.8-13.el7.x86_64.rpm | 99 kB 00:00:00
(2/2): libmcrypt-devel-2.5.8-13.el7.x86_64.rpm | 13 kB 00:00:00
--------------------------------------------------------------------------------------------------------
Total 1.2 MB/s | 112 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : libmcrypt-2.5.8-13.el7.x86_64 1/2
Installing : libmcrypt-devel-2.5.8-13.el7.x86_64 2/2
Verifying : libmcrypt-devel-2.5.8-13.el7.x86_64 1/2
Verifying : libmcrypt-2.5.8-13.el7.x86_64 2/2
Installed:
libmcrypt.x86_64 0:2.5.8-13.el7 libmcrypt-devel.x86_64 0:2.5.8-13.el7
Complete!成功！
最后升级PHP，指令：
yum install -y php56w php56w-opcache php56w-xml php56w-mcrypt php56w-gd php56w-devel php56w-mysql php56w-intl php56w-mbstring
