--- title: "Installation" description: Installation of a gentoo system tags: - gentoo - linux --- ## Introduction When installing a gentoo system for the first time, please refer to the wonderfull [gentoo handbook](https://wiki.gentoo.org/wiki/Handbook:AMD64). This page is just installation notes shorthand when you know exactly what you are doing. ## Installation media You can get a bootable iso or liveusb from https://www.gentoo.org/downloads/. I recommend the minimal one. To create a bootable usb drive juste use `dd` to copy the image on it. Then boot on this brand new installation media. Once you boot on the installation media, you can start sshd and set a temporary password and proceed with the installation more confortably from another machine : ```sh /etc/init.d/sshd start passwd ``` Don't forget to either run `dhcpcd` or manually set an ip and gateway to the machine. ## Partitionning There are several options depending on wether you need soft raid, full disk encryption or a simple root device with no additional complications. It will also differ if you are using a virtual machine or a physical one. ```sh tmux blkdiscard /dev/nvme0n1 sgdisk -n1:0:+2M -t1:EF02 /dev/nvme0n1 sgdisk -n2:0:+512M -t2:EF00 /dev/nvme0n1 sgdisk -n3:0:0 -t3:8300 /dev/nvme0n1 mkfs.fat -F 32 -n efi-boot /dev/nvme0n1p2 mkfs.xfs /dev/nvme0n1p3 mount /dev/sda3 /mnt/gentoo cd /mnt/gentoo ``` Make sure you do not repeat the mistake I too often make by mounting something to /mnt while using the liveusb/livecd. You will lose your shell if you do this and will need to reboot! ## Get the stage3 and chroot into it Get the stage 3 installation file from https://www.gentoo.org/downloads/. I personnaly use the non-multilib one from the advanced choices, since I am no longer using and 32bits software except steam, and I use steam from a multilib chroot. Put the archive on the server in /mnt/gentoo (you can simply wget it from there), then extract it : ```sh tar xpf stage3-*.tar.xz --xattrs-include='*.*' --numeric-owner mount /dev/nvme0n1p2 boot mount -R /proc proc mount -R /sys sys mount -R /dev dev chroot . ``` ## Initial configuration We prepare the local language of the system : ```sh echo 'LANG="en_US.utf8"' > /etc/env.d/02locale echo 'en_US.UTF-8 UTF-8' >> /etc/locale.gen locale-gen env-update && source /etc/profile echo 'nameserver 1.1.1.1' > /etc/resolv.conf ``` We set a loop device to hold the portage tree. It will be formatted with optimisation for the many small files that compose it : ```sh mkdir -p /srv/gentoo-distfiles truncate -s 10G /portage.img mke2fs -b 1024 -i 2048 -m 0 -O "dir_index" -F /portage.img tune2fs -c 0 -i 0 /portage.img mkdir /usr/portage mount -o loop,noatime,nodev /portage.img /usr/portage/ ``` We set default compilation options and flags. If you are not me and cannot rsync this location, you can browse it from https://packages.adyxax.org/x86-64/etc/portage/ : ```sh rsync -a --delete packages.adyxax.org:/srv/gentoo-builder/x86-64/etc/portage/ /etc/portage/ sed -i /etc/portage/make.conf -e s/buildpkg/getbinpkg/ echo 'PORTAGE_BINHOST="https://packages.adyxax.org/x86-64/packages/"' >> /etc/portage/make.conf ``` We get the portage tree and sync the timezone ```sh emerge --sync ``` ## Set hostname and timezone ```sh export HOSTNAME=XXXXX sed -i /etc/conf.d/hostname -e /hostname=/s/=.*/=\"${HOSTNAME}\"/ echo "Europe/Paris" > /etc/timezone emerge --config sys-libs/timezone-data ``` ## Check cpu flags and compatibility TODO ```sh emerge cpuid2cpuflags -1q cpuid2cpuflags gcc -### -march=native /usr/include/stdlib.h ``` ## Rebuild the system ```sh emerge --quiet -e @world emerge --quiet dosfstools app-admin/logrotate app-admin/syslog-ng app-portage/gentoolkit \ dev-vcs/git bird openvpn htop net-analyzer/tcpdump net-misc/bridge-utils \ sys-apps/i2c-tools sys-apps/pciutils sys-apps/usbutils sys-boot/grub sys-fs/ncdu \ sys-process/lsof net-vpn/wireguard-tools emerge --unmerge nano -q ``` ## Grab a working kernel Next we need to Grab a working kernel from our build server along with its modules. If you don't have one already, you have some work to do! Check the necessary hardware support with : ```sh i2cdetect -l lspci -nnk lsusb ``` TODO specific page with details on how to build required modules like the nas for example. ```sh emerge gentoo-sources genkernel -q ... ``` ## Final configuration steps ### fstab ```sh # /etc/fstab: static file system information. # # /dev/vda3 / ext4 noatime,discard 0 1 /dev/vda2 /boot vfat noatime 1 2 /portage.img /usr/portage ext2 noatime,nodev,loop 0 0 ``` ### networking ```sh echo 'hostname="phoenix"' > /etc/conf.d/hostname echo 'dns_domain_lo="adyxax.org" config_eth0="192.168.1.3 netmask 255.255.255.0" routes_eth0="default via 192.168.1.1"' > /etc/conf.d/net cd /etc/init.d ln -s net.lo net.eth0 rc-update add net.eth0 boot ``` ### Grub TODO especially the conf in /etc/default/grub when using an encrypted / In the case of UEFI use something like : ```sh grub-install --efi-directory=/boot/ /dev/nvme1n1 grub-mkconfig -o /boot/grub/grub.cfg ``` ### /etc/hosts ```sh scp root@collab-jde.nexen.net:/etc/hosts /etc/ ``` ### root account access ```sh mkdir -p /root/.ssh echo ' ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAILOJV391WFRYgCVA2plFB8W8sF9LfbzXZOrxqaOrrwco hurricane' > /root/.ssh/authorized_keys passwd ``` ### Add necessary daemons on boot ```sh rc-update add syslog-ng default rc-update add cronie default rc-update add sshd default ``` ## TODO ```sh net-firewall/shorewall ... rc-update add shorewall default sed '/PRODUCTS/s/=.*/="shorewall"/' -i /etc/conf.d/shorewall-init rc-update add shorewall-init boot net-analyzer/fail2ban echo '[sshd] enabled = true filter = sshd ignoreip = 127.0.0.1/8 10.1.0.0/24 37.187.103.36 137.74.173.247 90.85.207.113 bantime = 3600 banaction = shorewall logpath = /var/log/messages maxretry = 3' > /etc/fail2ban/jail.d/sshd.conf rc-update add fail2ban default app-emulation/docker /etc/docker/daemon.json { "iptables": false } rc-update add docker default app-emulation/lxd rc-update add lxd default ``` ## References - http://blog.siphos.be/2013/04/gentoo-protip-using-buildpkgonly/ - https://wiki.gentoo.org/wiki/Genkernel - https://wiki.gentoo.org/wiki/Kernel/Configuration - https://wiki.gentoo.org/wiki/Kernel - https://forums.gentoo.org/viewtopic-t-1076024-start-0.html - https://wiki.gentoo.org/wiki/Binary_package_guide#Setting_up_a_binary_package_host