Immediate adaption efforts are need – that’s what I feel when I started to mess around with the latest version of Redhat.
“Good! Adaptation, improvisation, but your weakness is not your technique.” – Morpheus
Systemd
First thing I notice is many services have been migrated to systemd. That means the traditional service and chkconfig commands are no longer working. Fortunately, systemd is quite easy to work with, for example:
systemctl enable mariadb
systemctl start mariadb
systemctl disable firewalld
sysctmctl -a | grep ntp
Also interesting is that systemd works on remote system with the -H switch. One can also configure systemd to monitor a service and restart it when necessary. For example, edit /usr/lib/systemd/system/httpd.service and add Restart=always to the [Service] section.
A more detail illustration can be found at here & here
XFS
The default filesystem is now XFS and mounted with the following options:
rw,relatime,seclabel,attr2,inode64,noquota
NIC name changes
NIC are now named after its port and slot. For instance, my vbox vm has its first NIC named after enp0s3. NIC names are assigned by systemd. In previous versions, they’re assigned by udev.
NIC teaming
It’s something completely new, see Redhat’s doc. I only managed to bring up a teamed connection with the graphical network manager. It’s not using the bonding module at all. To check a team’s status, do this:
[root@rhel7 ~]# teamdctl team0 state setup: runner: roundrobin ports: eth0 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up eth1 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up
Setting hostname
Is no longer done in ifcfg script. Run hostnamectl to set a hostname or update /etc/hostname
hostnamectl set-hostname test01.domain.local
Kernel and release code name
Stock kernel is now 3.10.0-123.el7.x86_64. The 7.0 release’s code name is Maipo. Why not call it Bond :)
Runlevel
Default runlevel is also controlled by systemd and /etc/inittab is no longer used. Good thing is inittab contains doc to change the default runlevel.
ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target
NTP
Although the ntp package is still available and is not included in default install, ntp service is reported to be running with timedatectl. It seems ntp has been replaced by chrony.
More to come…
References
- http://www.certdepot.net/rhel7-get-started-systemd/
- http://www.certdepot.net/rhel7-set-ntp-service/
- https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Networking_Guide/sec-Configure_a_Network_Team_Using-the_Command_Line.html
