Step1: Download driver source code--------------------------------------------------------------------------------------------------
https://www.realtek.com/en/component/zoo/category/network-interface-controllers-10-100-1000m-gigabit-ethernet-pci-express-software
FE Ethernet LINUX driver r8101 for kernel up to 5.6
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Step2: Download gcc, make *.deb--------------------------------------------------------------------------------------------------
PACKAGES="gcc" apt-get download $(apt-cache depends --recurse --no-recommends --no-suggests --no-conflicts --no-breaks --no-replaces --no-enhances --no-pre-depends ${PACKAGES} | grep "^w")
PACKAGES="make" apt-get download $(apt-cache depends --recurse --no-recommends --no-suggests --no-conflicts --no-breaks --no-replaces --no-enhances --no-pre-depends ${PACKAGES} | grep "^w")
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Step2: copy to USB & mount--------------------------------------------------------------------------------------------------
mount /dev/sda1 /mnt
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Step3: install--------------------------------------------------------------------------------------------------
cd /mnt/deb_cache
dpkg -i *.deb
cd /mnt/driver_src
./autorun
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Step4: netplan--------------------------------------------------------------------------------------------------
cd /etc/netplan
nano 00-installer-config.yaml
network: version: 2 renderer: networkd ethernets: enp1s0: addresses: [192.168.31.5/24] dhcp4: no optional: true gateway4: 192.168.31.1 nameservers: addresses: [192.168.31.1, 114.114.114.114, 8.8.8.8]
netplan apply
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