Как установить realtek-firmware на Debian 9.4

W: Possible missing firmware /lib/firmware/rtl_nic/rtl8168e-2.fw for module r8169
W: Possible missing firmware /lib/firmware/rtl_nic/rtl8168e-1.fw for module r8169
W: Possible missing firmware /lib/firmware/rtl_nic/rtl8168d-2.fw for module r8169
W: Possible missing firmware /lib/firmware/rtl_nic/rtl8168d-1.fw for module r816

sed -i.bak 's/stretch[^ ]* main$/& contrib non-free/g' /etc/apt/sources.list
apt update
apt install firmware-misc-nonfree firmware-netxen firmware-realtek
update-initramfs -u