This script install the Linux kernel driver to provide ENA support for CentOS 7.x and 6.x.

install_amzndriver_centos.sh

#!/usr/bin/env bash

# https://docs.aws.amazon.com/ja_jp/AWSEC2/latest/UserGuide/enhanced-networking-ena.html

amzn_driver_ver="1.5.3"
centos_ver=`sed -e 's/^CentOS\s\(Linux\s\|\)release\s\([0-9.]\+\)\s.\+$/\2/' /etc/centos-release`

#  Install the appropriate kernel-devel and kernel-headers
# --------------------------------------------------
yum install -y perl
rpm -ivh http://vault.centos.org/${centos_ver}/updates/x86_64/Packages/kernel-devel-$(uname -r).rpm
rpm -ivh http://vault.centos.org/${centos_ver}/updates/x86_64/Packages/kernel-headers-$(uname -r).rpm

#  Install dkms
# --------------------------------------------------
yum install -y wget
wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-$(rpm -E '%{rhel}').noarch.rpm
rpm -ivh epel-release-latest-$(rpm -E '%{rhel}').noarch.rpm
rm epel-release-latest-$(rpm -E '%{rhel}').noarch.rpm
sed -i 's/mirrorlist=https/mirrorlist=http/' /etc/yum.repos.d/epel.repo
sed -i 's/enabled=1/enabled=0/g' /etc/yum.repos.d/epel.repo
yum install -y --enablerepo=epel dkms

#  Install amzn-drivers
# --------------------------------------------------
yum update -y nss curl libcurl
yum install -y git
git clone https://github.com/amzn/amzn-drivers
mv amzn-drivers /usr/src/amzn-drivers-${amzn_driver_ver}

cat << EOS >> /usr/src/amzn-drivers-${amzn_driver_ver}/dkms.conf
PACKAGE_NAME="ena"
PACKAGE_VERSION="${amzn_driver_ver}"
CLEAN="make -C kernel/linux/ena clean"
MAKE="make -C kernel/linux/ena/ BUILD_KERNEL=$(uname -r)"
BUILT_MODULE_NAME[0]="ena"
BUILT_MODULE_LOCATION="kernel/linux/ena"
DEST_MODULE_LOCATION[0]="/updates"
DEST_MODULE_NAME[0]="ena"
AUTOINSTALL="yes"
EOS

dkms add -m amzn-drivers -v ${amzn_driver_ver}
dkms build -m amzn-drivers -v ${amzn_driver_ver}
dkms install -m amzn-drivers -v ${amzn_driver_ver}

#  Creates a list of module dependencies
# --------------------------------------------------
depmod

#  Create an initramfs
# --------------------------------------------------
dracut -f -v

#  Modify GRUB configuration to use eth0 for ENA
# --------------------------------------------------
if [[ ${centos_ver} =~ ^7 ]] ; then
  sed -i '/^GRUB\_CMDLINE\_LINUX/s/\"$/\ net\.ifnames\=0\"/' /etc/default/grub
  grub2-mkconfig -o /boot/grub2/grub.cfg
fi