Chapter 4. Post Installation Configuration

Red Hat Enterprise Linux Atomic Host is configured using the configuration files in the /etc/ directory. This is similar to the way that Red Hat Enterprise Linux 7 is configured. Because Red Hat Enterprise Linux Atomic Host is a minimal server product that has no desktop, the graphical configuration tools found in the GUI are not available.

4.1. Configuring Networking

If you did not configure networking during the installation you may configure it post-installation using the nmcli tool. The following commands create a network connection called atomic, set up a host name, and then activate that connection.

# nmcli con add type ethernet con-name atomic ifname eth0
# nmcli con modify my-office my-office ipv4.dhcp-hostname atomic ipv6.dhcp-hostname atomic
# nmcli con up atomic

For more details on how to use the nmcli tool, see Section 2.3.2. Connecting to a Network Using nmcli in the Red Hat Enterprise Linux 7 Networking Guide.

4.2. Registering RHEL Atomic Host

To enable software updates, you must register your Red Hat Enterprise Linux Atomic Host installation. This is done with the subscription-manager command as described below. By default, subscription-manager assumes that your system has Internet access with the ability to reach Red Hat software repositories. If you don’t have direct Internet access, you have a couple of options:

  • HTTP proxy: If your system is located on a network that requires the use of an HTTP proxy, see the Red Hat Knowledge Base Article on configuring subscription manager to use an HTTP proxy. The --name= option may be included if you wish to provide an easy-to-remember name to be used when reviewing subscription records.
  • Internal ostree mirror: If your location has no Internet access (even via an HTTP proxy), you can mirror the official Red Hat Enterprise Linux Atomic Host ostree repository for use in a way that is local to your environment. A procedure for setting up such a mirror is available in Using Atomic Host as an internal ostree mirror.
$ sudo subscription-manager register --username=<username> --auto-attach
Note

Red Hat Enterprise Linux Atomic Host works only with Red Hat Subscription Manager (RHSM). Red Hat Enterprise Linux Atomic Host does not work with RHN.

Note

Red Hat Enterprise Linux Atomic Host registers two product IDs. The first is Product ID 271, Red Hat Enterprise Linux Atomic Host. The second is Product ID 69, Red Hat Enterprise Linux Server. They both use the same entitlement.

A properly registered system will display both IDs as is shown below:

$ sudo subscription-manager list
+-------------------------------------------+
    Installed Product Status
+-------------------------------------------+
Product Name:   Red Hat Enterprise Linux Atomic Host
Product ID:     271
Version:        7
Arch:           x86_64
Status:         Subscribed
Status Details:
Starts:         02/27/2015
Ends:           02/26/2016

Product Name:   Red Hat Enterprise Linux Server
Product ID:     69
Version:        7.1
Arch:           x86_64
Status:         Subscribed
Status Details:
Starts:         02/27/2015
Ends:           02/26/2016

The subscription-manager command is also documented in Registering from the Command Line of the Red Hat Subscription Management guide.

4.3. Managing User Accounts

Currently, some system users that in Red Hat Enterprise Linux 7 would be listed in the /etc/passwd file have been relocated into the read-only /usr/lib/passwd file. Because applications on Red Hat Enterprise Linux Atomic Host are run inside Linux containers, this does not affect deployment. The traditional user management tools, such as useradd, write locally added users to the /etc/passwd file as expected.