ESCを押してから以下追記

inst.ks=http://192.168.100.2/ks/fc21macmini.cfg ip=192.168.100.9 netmask=255.255.255.0 gateway=192.168.100.1 nameserver=8.8.8.8

CentOS • View topic - Editing grub.cfg for EFI install options

fc21macmini.cfg

# version=DEVEL
# System authorization information
auth --enableshadow --passalgo=sha512

# Use CDROM installation media
# text
graphical
# Run the Setup Agent on first boot
firstboot --enable
ignoredisk --only-use=sda,sdb
# Keyboard layouts
keyboard --vckeymap=jp --xlayouts='jp'
# System language
lang ja_JP.UTF-8
# custom
firewall --disabled
selinux --disabled

# Network information
network  --bootproto=dhcp --device=enp3s0f0 --ipv6=auto --activate
network  --hostname=localhost.localdomain
# Root password
# (略)

# System timezone
timezone Asia/Tokyo --isUtc

# user追加
# (略)

# System bootloader configuration
bootloader --location=mbr --boot-drive=sda
# Partition clearing information
clearpart --all --initlabel --drives=sda,sdb
# 
part /boot/efi --fstype=efi --grow --size=200 --ondisk=sda
part /boot --fstype=ext3 --size=300 --ondisk=sda
part /mnt/hdd --fstype=ext4 --size=1 --grow --ondisk=sda
part swap --size=4000 --ondisk=sda
#
part / --fstype=xfs --size=1 --grow --ondisk=sdb

reboot

%packages
@core
%end

%addon com_redhat_kdump --disable --reserve-mb='128'
%end

%post --log=/root/ks-post-anaconda.log
set -x
yum update -y
yum clean all
%end