Chapter 13. DHCP
DHCPD is the daemon used in Red Hat Enterprise Linux to dynamically deliver and configure Layer 3 TCP/IP details for clients.
The dhcp package provides the DHCP server,
dhcpd
. Run the rpm -q dhcp
command to see if the dhcp package is installed. If it is not installed, run the following command as the root user to install it:
~]# yum install dhcp
13.1. DHCP and SELinux
When DHCPD is enabled, it runs confined by default. Confined processes run in their own domains, and are separated from other confined processes. If a confined process is compromised by an attacker, depending on SELinux policy configuration, an attacker's access to resources and the possible damage they can do is limited. The following example demonstrates the DHCPD and related processes running in their own domain. This example assumes the dhcp package is installed and that the DHCPD service has been started:
- Run the
getenforce
command to confirm SELinux is running in enforcing mode:~]$
getenforce
EnforcingThegetenforce
command returnsEnforcing
when SELinux is running in enforcing mode. - Run the
service dhcpd start
command as the root user to startDHCPD
:~]#
service dhcpd start
Starting dhcpd: [ OK ] - Run the
ps -eZ | grep dhcpd
command to view thedhcpd
processes:~]$
ps -eZ | grep dhcpd
unconfined_u:system_r:dhcpd_t:s0 5483 ? 00:00:00 dhcpdThe SELinux context associated with the dhcpd process isunconfined_u:system_r:dhcpd_t:s0
.