When attempting to upgrade PHP from 5.4 to 7.2 on CentOS 6.5, you might encounter dependency issues like:

Error: Package: libcurl-7.29.0-59.el7.x86_64 (epel)
       Requires: libssl.so.10(OPENSSL_1.0.1)(64bit)

This indicates your system is mistakenly trying to use EPEL 7 packages on CentOS 6. Let's verify the installed EPEL repo:

# List all enabled repositories
yum repolist enabled

# Check EPEL package version
rpm -qa | grep epel-release

First, remove the incorrect EPEL 7 repository:

# Remove EPEL 7 package
yum remove epel-release

# Clean YUM cache
yum clean all

Verify the removal by checking if any EPEL repositories remain:

ls -la /etc/yum.repos.d/epel*

Now install the correct EPEL 6.8 repository for CentOS 6:

# Download EPEL 6 release package
wget https://archive.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm

# Install the package
rpm -ivh epel-release-6-8.noarch.rpm

# Verify installation
rpm -qa epel-release

With the proper repository in place, you can now proceed with the PHP upgrade:

# Install the Remi repository for PHP 7.2
rpm -Uvh http://rpms.remirepo.net/enterprise/remi-release-6.rpm

# Enable PHP 7.2 repository
yum-config-manager --enable remi-php72

# Install PHP 7.2 and required extensions
yum install php php-cli php-common php-mysql php-gd php-mbstring

Verify the PHP version:

php -v

If you encounter dependency problems after these steps:

# Resolve dependencies
yum deplist php

# Check for package conflicts
package-cleanup --dupes
package-cleanup --problems

Ensure all repositories are properly configured:

# Check enabled repositories
yum repolist enabled

# Verify repository priorities
yum install yum-plugin-priorities

This complete process should resolve your EPEL repository mismatch and allow successful PHP 7.2 installation on CentOS 6.5.

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When attempting to upgrade PHP from 5.4 to 7.2 on CentOS 6.5, you might encounter dependency conflicts caused by an incorrectly installed EPEL 7 repository. The system may show errors related to libcurl or other packages trying to pull dependencies from EPEL 7 instead of EPEL 6.8.

First, verify which EPEL repositories are currently installed on your system:

yum repolist | grep epel
rpm -qa | grep epel-release

This will show you all enabled EPEL repositories. If you see "epel-release-7" or similar, it indicates EPEL 7 is installed.

To cleanly remove the EPEL 7 repository:

yum remove epel-release
rpm -e epel-release-7*
rm -f /etc/yum.repos.d/epel*
yum clean all

This sequence ensures complete removal of all EPEL 7 packages and cached data.

Now install the correct EPEL version for CentOS 6:

rpm -Uvh https://archives.fedoraproject.org/pub/archive/epel/6/x86_64/epel-release-6-8.noarch.rpm
yum clean all
yum makecache

Verify the installation:

yum repolist | grep epel
cat /etc/yum.repos.d/epel.repo

With the correct repository in place, you can now proceed with the PHP upgrade:

yum install https://rpms.remirepo.net/enterprise/remi-release-6.rpm
yum --enablerepo=remi-php72 install php php-common php-opcache php-mcrypt php-cli php-gd php-curl php-mysql

Check the PHP version to confirm:

php -v

To ensure all future installations come from the correct repositories:

yum install yum-plugin-priorities
Edit /etc/yum.repos.d/epel.repo and add:
priority=10

This gives EPEL 6.8 lower priority than base repositories.

If you encounter dependency problems after the repository change:

package-cleanup --problems
package-cleanup --dupes
yum-complete-transaction

These commands help resolve leftover dependency issues from the repository change.