New to Centos 7

[SCSIraidGURU]

I have an HP DL360e Gen8 server with 12 cores, 96GB of RAM, running VMWare 6U3 with two TB datastores in hardware RAID 1. I am working on my CompTIA Linux+ Cert. I installed a few CentOS 7 servers and Ubuntu 16.04.5 servers. I created a WordPress server on CentOS 7 and one on Ubuntu 16.04.5. I have another CentOS 7 file server. I find it strange that CentOS 7 uses kernel 3.10 by default. I took my Files server and did elrepo upgrade to kernel 4.18.8 to test with. I left WordPress on 3.10 because it hosts many web sites. Why does CentOS 7 stay on such an old kernel by default? Is 4.18.8 stable? I still have the older kernels of 3.10 on it to revert back. Files have just a few things on it. I use Veeam to backup the VM. So I can revert it back.

[hunter86_bg]

CentOS (just like Oracle Linux) is built from RHEL sources but with stripped out "Red Hat" proprietary stuff like trademarks, logos, etc.The project tries to keep full binary compatibility and I can assure you that CentOS is quite stable.
The idea in RHEL is to provide a stable platform for your enterprise solution.When you install your proprietary software , you want to be sure that it will work till the EOL of your OS.You can imagine if you do a minor update from 7.5 to 7.6 and the kernel jumps from 3.10 to 4.xx and your software stops working. That's why RHEL was built with kernel 3.10 (I guess this was available during the Alpha version) and is backporting security and other commits from the upstream.
Of course this causes problems when you need php7 or newer kernel, but is good for stability.

If you need a newer kernel - you might consider Fedora (if you want the Red Hat family) or openSuSE Tumbleweed, while openSuSE leap is more like CentOS to RHEL.

[SCSIraidGURU]

When I installed Word Press on Day 1 I upgraded mySQL and PHP. Every site for WordPress said get on the latest PHP and MySQL for less issues.

Linux
[root@CENTOS7WEB ~]# hostnamectl
Static hostname: CENTOS7WEB
Icon name: computer-vm
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-862.6.3.el7.x86_64
Architecture: x86-64
[root@CENTOS7WEB ~]#
Apache
[root@CENTOS7WEB ~]# httpd -v
Server version: Apache/2.4.6 (CentOS)
Server built: Jun 27 2018 13:48:59
[root@CENTOS7WEB ~]#
MySQL
MariaDB
[root@CENTOS7WEB ~]# mysql -V
mysql Ver 15.1 Distrib 10.3.8-MariaDB, for Linux (x86_64) using readline 5.1
[root@CENTOS7WEB ~]#
PHP
[root@CENTOS7WEB ~]# php -v
PHP 7.0.31 (cli) (built: Jul 19 2018 17:59:49) ( NTS )
Copyright (c) 1997-2017 The PHP Group
Zend Engine v3.0.0, Copyright (c) 1998-2017 Zend Technologies
with Zend OPcache v7.0.31, Copyright (c) 1999-2017, by Zend Technologies
[root@CENTOS7WEB ~]#

[TrevorH]

Please see https://access.redhat.com/security/updates/backporting/ for information on backporting of security fixes and features in CentOS and RHEL. Additionally https://access.redhat.com/solutions/2074 may also be of use.

[SCSIraidGURU]

Thanks for the links. I use a Fortinet 60E Firewall and 221C WAP with the latest firmware. I installed Godaddy SSL Certificates and setup SSL Deep Inspection on the firewall for every https packet. I have a Syslog-NG server for my logs.