A Major Difference Between RHEL 6 vs RHEL 7 Here you go

RHEL 7 vs RHEL 6

Red Hat Enterprise Linux 7 is an Light weight and minimized Operating system. RHEL 7 changes are huge effect to enterprise.

Let's see what changed in RHEL 7 as per administration prospective.

• First one is Anaconda Installer Completely new.
• Grub version updated from 0.97 to Grub 2 fast booting
• Procedure of bypassing root password at booting process completely different than RHEL 6/5 
• There is no SysV Initd in RHEL 7 it's an new Systemd
• Run Levels are changed to Targets.
• Default file system in RHEL 7 is XFS. XFS file system supports 550TB of each partition size in 64-bit.
• Directories /bin /sbin /lib and /lib64 are moved under /usr/
• Network Interface Names are changed from eth0 to ens.xxx
• New concept to create multiple profiles top of one Ethernet card, No need of changing IP addresses and settings every time when you connect different networks, simply activate different profile.
• GNOME version changed from 2 to 3
• No classic registration system, completely changed to Red Hat subscription Manager
• Default database is MariaDB instead of MySQL
• Cluster Manager has been changed to Pacemaker and Corosync
• Ifconfig command is deprecated, replaced with ip command
•  User Identification Numbers (UID's) changed from 500 to 1000, which means when you create new normal user in RHEL 7 will get UID from 1000 to 65534
• locate command is changed to mlocate
•  yum commands are changed little bit

 

Feature Name	RHEL 6	RHEL 7
Default File System	Ext4	XFS
Kernel Version	2.6.xx	3.10.xx
Release Name	Santiago	Maipo
Gnome Version	GNOME 2	GNOME 3.8
KDE Version	4.6	4.1
Release Date	10-Nov-10	10-Jun-14
NFS Version	NFS 4	NFS 4.1. NFS V2 is deprecated in RHEL 7
Samba Version	3.6	4.4
Default Database	MariaDB	MySQL
Cluster Resource Manager	Rgmanager	Pacemaker
Network Grouping	Team Driver will support multiple types of Teaming methods called Active-Backup, Load-balancing and Broadcase	Bonding can be done as Active-Backup, XOR, IEEE and Loac Balancing
KDUMP	RHEL 7 can be supported up to 3TB	Kdump does't support with large RAM Size
Boot Loader	Grub 2 /boot/grub2/grub.cfg	Grub 0.97  /boot/grub/grub.conf
File System Check	xfs_replair - Inode blockmap checks -Inode allocation map checks -Inode size check -Directory check -Path Name check -Link count check -Freemap check -Super block check	e2fsck -Inode check. Block and size check --Directory Structure check -Directory Link Check -reference count check -Group Summary Check
Process ID	Systemd (1)	Initd (1)
Port Security	Firewalld instead of iptables. Iptables can also support with RHEL 7, but we can't use both of them at the same time. Firewall will not allow any port until and unless you enabled it.	iptables by default service port is enabled when service is switched on.
Boot Time	40 Sec	20 Sec
File System Size	EXT4 16TB with XFS 100TB	XFS 500TB with EXT4 16TB
Processor Architecture	32Bit and 64Bit	Only 64Bit.
Network Configuration Tool	steup	nmtui
Hostname Config File	/etc/sysconfig/network	/etc/hostname No need to edit hostname file to write permanent hostname simply use hostnamectl command
Interface Name	eth0	ens33xxx
Managing Services	service sshd start service sshd restart chkconfig sshd on	systemctl start sshd.service systemctl restart sshd.service systemctl enable sshd.service
System Logs	/var/log/	/var/log journalctl
Run Levels	runlevel 0 - Power Off runlevel 1 - Single User Mode runlevel 2 - Multi User without Networking runlevel 3 - Multi User CLI runlevel 4 - Not USed runlevel 5 - GUI Mode runlevel 6 - Restart	There is no run levels in RHEL 6. Run levels are called as targets Poweroff.target rescue.target multi-user.target graphical.target reboot.target
UID Information	Normal User UID will start from 500 to 65534 System Users UID will start from 1 to 499	Normal User UID start from 1000 - 65534 System Users UID will start from 1 to 999 Because Services are increased compare to RHEL 6
By Pass Root Password Prompt	append 1 or s or init=/bin/bash to Kernel command line	Append rd.break or init=/bin/bash to kernel command line
Rebooting and Poweroff	poweroff - init 0 reboot - init 6	systemctl poweroff systemctl reboot
YUM Commands	yum groupinstall yum groupinfo	yum group install yum group info

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