First play with CentOS 7.0

As I didn’t get chance to have a play with the pre-release CentOS 7.0 builds I decided to wait until DigitalOcean↗ lauched their image↗ which they did just in time for the weekend.

Check the IP Address

First thing I did was type in ifconfig and got …..

[root@server ~]# ifconfig
-bash: ifconfig: command not found

….. not a good start, have dabbled with a Fedora↗ when I installed OpenShift I remembered about the ip command …..

[root@server ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
 inet 127.0.0.1/8 scope host lo
 valid_lft forever preferred_lft forever
 inet6 ::1/128 scope host
 valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
 link/ether ff:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff
 inet 123.123.123.123/24 brd 123.123.123.255 scope global eth0
 valid_lft forever preferred_lft forever
 inet6 fe80::fe80:fe80:fe80:fe80/64 scope link
 valid_lft forever preferred_lft forever

….. I can see a lot of muscle memory having to be re-learned.

Restarting services

Next up is a change I was expecting, the introduction of systemd↗ …..

[root@server ~]# yum install httpd
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirror.awanti.com
 * extras: mirror.awanti.com
 * updates: mirror.awanti.com
Resolving Dependencies
 → Running transaction check
 - -> Package httpd.x86_64 0:2.4.6–17.el7.centos.1 will be installed
 → Finished Dependency Resolution

Dependencies Resolved

======================================================================================================
 Package Arch Version Repository Size
======================================================================================================
Installing:
 httpd x86_64 2.4.6–17.el7.centos.1 base 2.7 M

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

Total download size: 2.7 M
Installed size: 9.3 M
Is this ok [y/d/N]: y
Downloading packages:
httpd-2.4.6–17.el7.centos.1.x86_64.rpm | 2.7 MB 00:00:01
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
 Installing : httpd-2.4.6–17.el7.centos.1.x86_64 1/1
 Verifying : httpd-2.4.6–17.el7.centos.1.x86_64 1/1

Installed:
 httpd.x86_64 0:2.4.6–17.el7.centos.1

Complete!
[root@server ~]# service httpd restart
Redirecting to /bin/systemctl restart httpd.service

…. as you can see it did what I asked, but dropped some hints that I should have used systemctl restart httpd. What would systemctl status httpd give us …..

[root@server ~]# systemctl status httpd
httpd.service - The Apache HTTP Server
 Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled)
 Active: active (running) since Sun 2014–07–13 13:24:45 EDT; 4s ago
 Process: 21656 ExecStop=/bin/kill -WINCH ${MAINPID} (code=exited, status=0/SUCCESS)
 Main PID: 21661 (httpd)
 Status: “Processing requests…”
 CGroup: /system.slice/httpd.service
 ├─21661 /usr/sbin/httpd -DFOREGROUND
 ├─21663 /usr/sbin/httpd -DFOREGROUND
 ├─21664 /usr/sbin/httpd -DFOREGROUND
 ├─21665 /usr/sbin/httpd -DFOREGROUND
 ├─21666 /usr/sbin/httpd -DFOREGROUND
 └─21667 /usr/sbin/httpd -DFOREGROUND

Jul 13 13:24:45 server.domain.com systemd[1]: Starting The Apache HTTP Server…
Jul 13 13:24:45 server.domain.com systemd[1]: Started The Apache HTTP Server.

….. now thats a lot more useful that what serivce httpd status used to give.

Other highlights & changes

Version number

The initial release of CentOS 7.0 is actually 7.0–1406 (see the numbering part of this notice↗)

New Kernel

CentOS 7.0–1406 ships with 3.10.0–123, which is alot better than the previous 2.6.x kernel which shipped with CentOS 6

FirewallD

CentOS now comes with FirewallD, I can’t say I have ever used it before so more reading↗ is needed↗

XFS

XFS is now the default file system when you install, though DigitalOcean↗ have stuck with ext4

Linux Containers

Docker (which I have written about here, here and here) is now fully support out of the box with no need to install EPEL↗, in fact, at the time of writing the CentOS repo was more up-to-date than EPEL.

[root@server ~]# yum list | grep docker
docker.x86_64 0.11.1–22.el7.centos extras
docker-registry.noarch 0.6.8–8.el7 extras

Other software

Some changes to later software across the board, here are the highlights ……

PHP↗ is version 5.4.16
Apache↗ is at version 2.4.6–17
Ruby↗ is at version 2.0.0.353
Python↗ is at version 2.7.5–16
Go↗ is at version 1.2–7
MySQL↗ has been replaced with MariaDB↗ version 5.5.37
PostgreSQL↗ is at version 9.2.7–1