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Even though it is not mandatory, it is good practice to exclude the Ethernet interfaces that will be used by the guest system running on Charon-PAR from being managed by the NetworkManager.  This can be done for physical NICs dedicated to the guest operating system, or for virtual bridge and TAP configurations (that allow the host and the guest to share a physical interface).

In a network environment controlled by the NetworkManager, the NetworkManager—if configured accordingly—will create and manage the interface configuration files. This may create conflicts with the requirements of the Charon-PAR guest system. If this is the case, a manual configuration should be considered.

There are several options to prevent such problems:

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Example of a minimal ifcfg-<interface> file in /etc/sysconfig/network-scripts/:

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NM_CONTROLLED=no
DEVICE=eth0
HWADDR=00:11:22:33:44:55
BOOTPROTO=none
ONBOOT=yes

Example of a minimal bridge configuration via ifcfg-<interface> files in /etc/sysconfig/network-scripts/:

DEVICE=br_enp0s8
NAME=br_enp0s8
TYPE=Bridge
ONBOOT=yes
DEFROUTE=yes
STP=no
BOOTPROTO=none
IPADDR=10.0.0.1
NETMASK=255.255.255.0
GATEWAY=10.0.0.10
NM_CONTROLLED=no

DEVICE=enp0s8
NAME=enp0s8
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=no
BRIDGE=br_enp0s8

DEVICE=tap0_enp0s8
NAME=tap0_enp0s8
BRIDGE=br_enp0s8
TYPE=Tap
ONBOOT=yes
NM_CONTROLLED=no

Please refer to your host system’s man-pages for additional information about the NetworkManager.

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