Preparations¶
What you need:
- 1x 16GB SLC USB stick to run the dom0 from
- 1x 1GB Installer USB stick
- 1x Laptop or similar to run the setup (initial installation) from
Later (when you are ready to deploy)
- 1x Proper server to run the alpine dom0 on (e.g. HP MicroServer or similar)
Plug in the Installer USB stick in your workstation an add the alpine-xen iso to it.
from dmesg
[162562.819054] sd 5:0:0:0: [sdb] 2046240 512-byte logical blocks: (1.04 GB/999 MiB) [162562.823977] sdb: sdb1
Put the installation iso on the installer usb-stick
$ sudo dd if=/tmp/alpine-xen-3.5.2-x86_64.iso of=/dev/sdb 299008+0 records in 299008+0 records out 153092096 bytes (153 MB) copied, 56.1059 s, 2.7 MB/s $ sync
unplug the usb-stick from the workstation.
Installation on the SLC stick¶
Boot the laptop from the installer usb-stick.
When booted connect the 16GB SLC stick as well and then partition it with
- Small partition of 1GB for booting the dom0
- LVM partition that will be holding supporting domUs
With supporting domUs I am referring to network driver domain and storage driver domain. The storage driver domain for instance uses storage connected to a local PCI exported PCIe card or alternatively bringing in storage via iSCSI from a remote iscsi-target.
Partition table for the SLC USB device:
Disk /dev/sdf: 15.9 GB, 15977152512 bytes 64 heads, 32 sectors/track, 15237 cylinders Units = cylinders of 2048 * 512 = 1048576 bytes Device Boot Start End Blocks Id System /dev/sdf1 * 1 955 977904 c Win95 FAT32 (LBA) /dev/sdf2 956 15237 14624768 8e Linux LVM
Note: you might need to unplug/replug the stick after partitioning it.
Run apk add syslinux to install syslinux package
Run modprobe vfat to load the vfat kernel module
Create a file system on the bootable vfat partition
# mkfs.vfat /dev/sdf1
Run the setup-bootable script to add Alpine Linux to the USB stick and make it bootable (replacing sdf with your USB stick name):
Note /media/sdb could be other mountpoint as well (e.g. /media/usb), check in the output of df (before running setup-bootable).
# setup-bootable /media/sdb /dev/sdf1
Now you can reboot the laptop from the 16GB SLC stick (unplug the Installer USB stick).
Basic alpine host setup¶
After reboot, login on console again.
Note: you must setup working networking with Internet access in alpine-setup.
Basic dom0/host setup
# apk add syslinux bridge # setup-alpine
choose to bridge eth0 if any domUs will share eth0 with dom0, name it br_eth0
Which disk(s) would you like to use: none Enter where to store configs: usb Enter apk cache directory: /media/usb/cache
Save changes to the USB drive
dom0:~# lbu commit
XEN dom0 setup¶
dom0:~# setup-xen-dom0 dom0:~# lbu commit
Setup LVM (before continuing make sure what name the stick have by checking df output)
dom0:~# apk add lvm2 dom0:~# rc-update add lvm dom0:~# pvcreate /dev/sdb2 Physical volume "/dev/sdb2" successfully created. dom0:~# vgcreate vg_domU /dev/sdb2 Volume group "vg_domU" successfully created dom0:~# lbu commit
Install pv-grub2 from edge/testing
dom0:~# echo "@edge http://nl.alpinelinux.org/alpine/edge/testing" >> /etc/apk/repositories dom0:~# apk add grub-xenhost@edge --update-cache
domU installation¶
Now follow Alpine Linux as a XEN domU to setup a network driver domain called fw. Store alpine-extended-3.4.4-x86_64.iso in /media/usb and you can reuse /media/usb/boot/vmlinuz-grsec and /media/usb/boot/initramfs-grsec from the dom0 to boot the domU installer from.
E.g. directory for alpine-extended-3.4.4-x86_64.iso
dom0:~# mkdir /media/usb/domu_installer
Example /etc/xen/fw.cfg
# fw domU vcpus = '1' memory = '128' kernel = "/media/usb/boot/vmlinuz-grsec" ramdisk = "/media/usb/boot/initramfs-grsec" extra="alpine_dev=hdc:iso9660 modules=loop,squashfs,sd-mod,usb-storage console=hvc0" disk = [ 'file://media/usb/domu_installer/alpine-extended-3.4.4-x86_64.iso,hdc:cdrom,r', 'phy:/dev/vg_domU/fw-disk,xvda1,w', ] name = 'fw' vif = [ 'mac=00:16:3E:AA:BB:CC,bridge=br_eth0' ] on_poweroff = 'destroy' on_reboot = 'restart' on_crash = 'restart'
Example creation of storage for the new domU
dom0:~# lvcreate -n fw-disk -L 512M vg_domU
Logical volume "fw-disk" created.
dom0:~# apk add e2fsprogs
dom0:~# mkfs.ext4 /dev/vg_domU/fw-disk
dom0:~# xl create /etc/xen/fw.cfg -c
Test rest of the steps as described in Alpine Linux as a XEN domU. But
make sure to install the iptables and bridge packages as well.
Make the fw domU start at boot
dom0:~# cd /etc/xen/auto dom0:/etc/xen/auto# ln -s ../fw.cfg 00-fw.cfg dom0:/etc/xen/auto# rc-update add xendomains dom0:/etc/xen/auto# lbu commit
XEN dom0 mem (optional)¶
When the dom0 boots from the SLC USB stick the bootloader is syslinux, hence dom0_mem should be configured in syslinux.cfg.
Before editing make the usb stick writeable
dom0:~# mount /media/usb -o remount,rw
Edit /media/usb/boot/syslinux/syslinux.cfg and add dom0_mem=1024M. A lower value will not work as the dom0 is running on a RAM disk.
Example after editing
TIMEOUT 20 PROMPT 1 DEFAULT grsec LABEL grsec MENU LABEL Xen/Linux grsec KERNEL /boot/syslinux/mboot.c32 APPEND /boot/xen.gz dom0_mem=1024M --- /boot/vmlinuz-grsec modules=loop,squashfs,sd-mod,usb-storage quiet nomodeset --- /boot/initramfs-grsec
After editing make the usb stick readonly
dom0:~# mount /media/usb -o remount,ro
Note: 1024M will not be enough to upgrade the kernel with the update-kernel command.
dom0 kernel update¶
You can update the kernel by putting <hostname>.apkovl.tar.gz on a freshly installed USB stick or with the update-kernel
command. However using update-kernel requires more dom0_mem, I use 1536M.
Free space on / need to be about 700MB free for update-kernel to complete.
Example with too little free:
dom0:~# df -h / Filesystem Size Used Available Use% Mounted on tmpfs 616.8M 205.4M 411.4M 33% /
Check free RAM
dom0:~# free -m
total used free shared buffers cached
Mem: 1285 464 821 205 2 293
-/+ buffers/cache: 168 1117
Swap: 0 0 0
Add more RAM to tmpfs mounted on /
dom0:~# mount -o remount,size=900M / dom0:~# df -h / Filesystem Size Used Available Use% Mounted on tmpfs 900.0M 205.1M 694.9M 23% /
Now update-kernel can be used.
dom0:~# mount -o remount,rw /media/usb dom0:~# update-kernel dom0:~# mount -o remount,ro /media/usb
Now you can reboot the dom0 to the updated kernel.