%general-entities; ]> Configuring the network Script network configuring This section only applies if a network card is to be configured. If a network card will not be used, there is likely no need to create any configuration files relating to network cards. If that is the case, remove the network symlinks from all run-level directories (/etc/rc.d/rc*.d). Creating Network Interface Configuration Files Which interfaces are brought up and down by the network script depends on the files and directories in the /etc/sysconfig/network-devices hierarchy. This directory should contain a directory for each interface to be configured, such as ifconfig.xyz, where xyz is a network interface name. Inside this directory would be files defining the attributes to this interface, such as its IP address(es), subnet masks, and so forth. If the /etc/sysconfig/network-devices directory is to be renamed or moved, make sure to edit the /etc/sysconfig/rc file and update the network_devices option by providing it with the new path. New files are created in this directory. The following command creates a sample ipv4 file for the eth0 device: cd /etc/sysconfig/network-devices && mkdir ifconfig.eth0 && cat > ifconfig.eth0/ipv4 << "EOF" ONBOOT=yes SERVICE=ipv4-static IP=192.168.1.1 GATEWAY=192.168.1.2 PREFIX=24 BROADCAST=192.168.1.255 EOF The values of these variables must be changed in every file to match the proper setup. If the ONBOOT variable is set to yes the network script will bring up the Network Interface Card (NIC) during booting of the system. If set to anything but yes the NIC will be ignored by the network script and not brought up. The SERVICE variable defines the method of obtaining the IP address. The LFS bootscripts have a modular IP assignment format, and creating additional files in the /etc/sysconfig/network-devices/services directory allows other IP assignment methods. This is commonly used for Dynamic Host Configuration Protocol (DHCP), which is addressed in the BLFS book. The GATEWAY variable should contain the default gateway IP address, if one is present. If not, then comment out the variable entirely. The PREFIX variable needs to contain the number of bits used in the subnet. Each octet in an IP address is 8 bits. If the subnet's netmask is 255.255.255.0, then it is using the first three octets (24 bits) to specify the network number. If the netmask is 255.255.255.240, it would be using the first 28 bits. Prefixes longer than 24 bits are commonly used by DSL- and cable-based Internet Service Providers (ISPs). In this example (PREFIX=24), the netmask is 255.255.255.0. Adjust according to the specific subnet. Creating the /etc/resolv.conf File /etc/resolv.conf If the system is going to be connected to the Internet, it will need some means of Domain Name Service (DNS) name resolution to resolve Internet domain names to IP addresses, and vice versa. This is best achieved by placing the IP address of the DNS server, available from the ISP or network administrator, into /etc/resolv.conf. Create the file by running the following: cat > /etc/resolv.conf << "EOF" # Begin /etc/resolv.conf domain {[Your Domain Name]} nameserver [IP address of your primary nameserver] nameserver [IP address of your secondary nameserver] # End /etc/resolv.conf EOF Replace [IP address of the nameserver] with the IP address of the DNS most appropriate for the setup. There will often be more than one entry (requirements demand secondary servers for fallback capability). If you only need or want one DNS server, remove the second nameserver line from the file. The IP address may also be a router on the local network.