X-Git-Url: https://git.adam-barratt.org.uk/?a=blobdiff_plain;f=input%2Fhowto%2Finstall-kvm.creole;h=7f1bbb87b0b5ab534437c919bac55b8f8bbc07ba;hb=b3da29d54a4a7d976d2ae94d0c70578add70aea1;hp=e648ec7e412bdec8c75728b4dade4be8ea9ce968;hpb=dc08619130a77a1f557f907d768a4d7e626ecd55;p=mirror%2Fdsa-wiki.git

diff --git a/input/howto/install-kvm.creole b/input/howto/install-kvm.creole
index e648ec7..7f1bbb8 100644
--- a/input/howto/install-kvm.creole
+++ b/input/howto/install-kvm.creole
@@ -1,5 +1,9 @@
 == Setup a new kvm domain fast ==
 
+=== guest setup ===
+
+or: how to install Debian.
+
 Define a shell function
 
 {{{
@@ -7,11 +11,37 @@ Define a shell function
 setup_env() {
  echo -n "New hostname: " &&
  export LC_ALL=C &&
- read host &&
+ read guest &&
  target=/mnt/target &&
  mirror=`cat /etc/apt/sources.list /etc/apt/sources.list.d/debian.list 2>/dev/null | awk '/^deb.*debian/ {print $2; exit}'` &&
- vg=`vgdisplay -c | awk -F: '{print $1;exit}' | sed 's/ *//g'` &&
- echo "Chosen vg is $vg" &&
+ vgdefault=`vgdisplay -c | awk -F: '{print $1;exit}' | sed 's/ *//g'` &&
+ echo -n "Volume group? [$vgdefault]: " &&
+ read vg &&
+ if [ "$vg" = "" ]; then vg="$vgdefault"; fi &&
+ echo -n "Use lvm for non-swap partitions? [Y/n] " &&
+ read use_lvm &&
+ if [ "$use_lvm" = "n" ]; then
+   : SAN, as in the msa2012i at ubcece &&
+   : requires that it is already setup &&
+   dev_root="/dev/mapper/$guest-root" &&
+   dev_boot="/dev/mapper/$guest-boot" &&
+   echo "Root device will be $dev_root" &&
+   echo "Boot device will be $dev_boot" &&
+   echo "Make sure they exist already." &&
+   fs=xfs
+ else
+   use_lvm="y" &&
+   dev_root="/dev/mapper/$vg-$guest--root" &&
+   dev_boot="/dev/mapper/$vg-$guest--boot" &&
+   echo "Root device will be $dev_root" &&
+   echo "Boot device will be $dev_boot" &&
+   fs=ext3
+ fi &&
+ dev_swap="/dev/mapper/$vg-$guest--swap" &&
+ echo -n "Use a /boot filesystem? [Y/n] " &&
+ read use_boot &&
+ echo "Swap device will be $dev_swap" &&
+ echo "fs is $fs"
  echo "Chosen mirror is $mirror"
 }
 }}}
@@ -24,28 +54,46 @@ setup_env
 
 Then install base:
 
+The way we lay out the filesystems by default is that we have one 4g /
+filesystem, a swap, and a tiny boot filesystem.  On the host we make
+a new LVM logical volume for each of the three.  Only the LV that will
+take the guest's boot will actually be partitioned - into a single boot
+partition.  That's so we can install grub into the MBR and have the system
+start just like a real system.  Root and swap are put directly onto the
+logical volume, without partitioning it at all.  This makes getting to the
+data from the host easier - no need to run kpartx - and it makes growing
+trivial.
+
 {{{
 #######
 # install base
 
- apt-get install debootstrap kpartx &&
- lvcreate -L 128m -n "$host"-boot /dev/"$vg" &&
- lvcreate -L 4g -n "$host"-root /dev/"$vg" &&
- lvcreate -L 4g -n "$host"-swap /dev/"$vg" &&
+ apt-get install debootstrap debian-archive-keyring kpartx &&
+ if [ "$use_lvm" = "y" ]; then
+   if [ "$use_boot" != "n" ] ; then
+     lvcreate -L 128m -n "$guest"-boot /dev/"$vg"
+   fi &&
+   lvcreate -L 4g -n "$guest"-root /dev/"$vg"
+ fi &&
+ lvcreate -L 4g -n "$guest"-swap /dev/"$vg" &&
  : &&
- ( echo ',,L,*' | sfdisk /dev/"$vg"/"$host"-boot ) &&
- kpartx -v -a /dev/"$vg"/"$host"-boot &&
- mkfs.ext3 /dev/mapper/"$vg"-"$host"--boot1 &&
- mkfs.ext3 /dev/"$vg"/"$host"-root &&
- mkswap /dev/"$vg"/"$host"-swap &&
+ if [ "$use_boot" != "n" ] ; then
+   ( echo ',,L,*' | sfdisk "$dev_boot" ) &&
+   kpartx -v -a "$dev_boot" &&
+   mkfs."$fs" "$dev_boot"1
+ fi &&
+ mkfs."$fs" "$dev_root" &&
+ mkswap "$dev_swap" &&
  : &&
  mkdir -p "$target" &&
- mount /dev/"$vg"/"$host"-root "$target" &&
- mkdir -p "$target/boot" &&
- mount /dev/mapper/"$vg"-"$host"--boot1 "$target/boot" &&
+ mount "$dev_root" "$target" &&
+ if [ "$use_boot" != "n" ] ; then
+   mkdir -p "$target/boot" &&
+   mount "$dev_boot"1 "$target/boot"
+ fi &&
 
  cd "$target" &&
- debootstrap --variant=minbase lenny . "$mirror"
+ debootstrap --variant=minbase --keyring=/usr/share/keyrings/debian-archive-keyring.gpg lenny . "$mirror"
 }}}
 
 And finalize the setup:
@@ -53,7 +101,7 @@ And finalize the setup:
 {{{
 #######
 # finish setup
- echo "$host" > etc/hostname &&
+ echo "$guest" > etc/hostname &&
  cat > etc/hosts << EOF &&
 127.0.0.1       localhost
 
@@ -72,32 +120,57 @@ EOF
  apt-key exportall | chroot . apt-key add - &&
  chroot . apt-get update &&
  echo "Apt::Install-Recommends 0;" > etc/apt/apt.conf.d/local-recommends &&
- chroot . apt-get install net-tools iproute ifupdown dialog vim netbase &&
- #chroot . apt-get remove --purge cpp dpkg-dev g++ gcc gcc-4.2-base libatm1 libdevmapper1.02.1 libgpm2 libc6-dev linux-libc-dev libstdc++6-4.3-dev binutils cpp-4.3 gcc-4.3 gettext-base libgmp3c2 libgomp1 libmpfr1ldbl libtimedate-perl
- # don't - it may start daemons
- #chroot . apt-get dist-upgrade
- chroot . apt-get install grub &&
- cp -av usr/lib/grub/x86_64-pc boot/grub &&
- grub << EOF &&
-device (hd0) /dev/mapper/$vg-$host--boot
+ chroot . apt-get install net-tools iproute ifupdown dialog vim netbase xfsprogs &&
+ if [ "$use_boot" != "n" ] ; then
+   chroot . apt-get install grub &&
+   cp -av usr/lib/grub/x86_64-pc boot/grub &&
+   grub << EOF &&
+device (hd0) $dev_boot
 root (hd0,0)
 setup (hd0)
 quit
 EOF
- # install a kernel image
- echo -e "do_symlinks = yes\nlink_in_boot = yes\ndo_initrd = yes" > etc/kernel-img.conf &&
- chroot . apt-get install linux-image-2.6-amd64
-
+   # install a kernel image
+   cat > etc/kernel-img.conf << EOF &&
+do_symlinks = yes
+link_in_boot = yes
+do_initrd = yes
+EOF
+   chroot . apt-get install linux-image-2.6-amd64 &&
+   cat >> etc/kernel-img.conf << EOF
+postinst_hook = /usr/sbin/update-grub
+postrm_hook   = /usr/sbin/update-grub
+EOF
+  else
+    cat > etc/kernel-img.conf << EOF &&
+do_symlinks = no
+do_initrd = yes
+EOF
+    chroot . apt-get install linux-image-2.6-amd64 &&
+   cat >> etc/kernel-img.conf << EOF
+postinst_hook = update-grub
+postrm_hook   = update-grub
+EOF
+    chroot . apt-get install grub2 &&
+    cp -av $dev_root dev/ &&
+    echo "(hd0) /dev/`basename $dev_root`" > boot/grub/device.map &&
+    chroot . grub-install /dev/"`basename $dev_root`" &&
+    sed -i -e 's/^#GRUB_TERMINAL=console/GRUB_TERMINAL=console/' etc/default/grub &&
+    chroot . update-grub &&
+    rm -v dev/"`basename $dev_root`" boot/grub/device.map &&
+    sed -i -e "s#dev/`basename $dev_root`#dev/vda#g" boot/grub/grub.cfg
+  fi
 }}}
 
 And a fstab and a boot loader config
 
 {{{
  # doesn't work: chroot . update-grub
- rootuuid=`vol_id /dev/"$vg"/"$host"-root "$target" | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
- swapuuid=`vol_id /dev/"$vg"/"$host"-swap "$target" | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
- bootuuid=`vol_id /dev/mapper/"$vg"-"$host"--boot1  | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
- cat > boot/grub/menu.lst << EOF &&
+ rootuuid=`vol_id "$dev_root" "$target" | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
+ swapuuid=`vol_id "$dev_swap" "$target" | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
+ if [ "$use_boot" != "n" ] ; then
+   bootuuid=`vol_id "$dev_boot"1  | awk -F= '$1=="ID_FS_UUID" {print $2}'` &&
+   cat > boot/grub/menu.lst << EOF
 default 0
 timeout 5
 color cyan/blue white/blue
@@ -113,11 +186,19 @@ initrd /initrd.img
 
 ### END DEBIAN AUTOMAGIC KERNELS LIST
 EOF
+ fi &&
+ if [ "$fs" = "ext3" ]; then
+   rootopts="errors=remount-ro"
+ else
+   rootopts="defaults"
+ fi
  cat > etc/fstab << EOF &&
-UUID=$rootuuid    /               ext3    errors=remount-ro 0       1
-UUID=$bootuuid    /boot           ext3    defaults        0       2
+UUID=$rootuuid    /               $fs    $rootopts 0       1
 UUID=$swapuuid    none            swap    sw              0       0
 EOF
+ if [ "$use_boot" != "n" ] ; then
+    echo "UUID=$bootuuid    /boot           $fs    defaults        0       2" >> etc/fstab
+ fi
  cat > etc/network/interfaces << EOF
 auto lo
 iface lo inet loopback
@@ -139,20 +220,53 @@ And unmount:
 
 {{{
   cd / &&
- umount "$target"/boot &&
+ if [ "$use_boot" != "n" ] ; then
+   umount "$target"/boot &&
+   kpartx -v -d "$dev_boot"
+ fi &&
  umount "$target" &&
- kpartx -v -d /dev/"$vg"/"$host"-boot &&
  rmdir "$target"
 }}}
 
-Setup a new kvm domain by creating a new file in /etc/dm-virt/`hostname/$host.xml.
+=== virsh setup ===
+
+Setup a new kvm domain by creating a new file in /etc/da-virt/`hostname/$guest.xml.
 
 * Properly configure hostname
 * Pick a new uuid ({{{uuidgen}}})
 * Setup block devices properly
 * pick a new and unique mac address (on d.o every kvm host has their own mac address space and the last block is changed for the guests, as in {{{..:..:..:..:<host byte>:<guest byte>}}}. )
 * virsh commands:
+** {{{virsh help}}}
 ** {{{virsh define foo.xml}}}
 ** {{{virsh start foo}}}
 ** {{{virsh destroy foo}}}
 ** {{{virsh vncdisplay foo}}} (and ssh -L 5900:localhost:<5900+x> $host  and  vnc localhost)
+
+=== post processing ===
+
+Do not forget to set a sane root password before installing ssh in the new kvm domain.
+
+=== when stuff goes wrong ===
+
+To get to the guest data from the host:
+
+{{{
+  setup_env
+ kpartx -v -a "$dev_boot" &&
+ mkdir -p "$target" &&
+ mount "$dev_root" "$target" &&
+ mkdir -p "$target/boot" &&
+ mount "$dev_boot"1 "$target/boot"
+}}}
+
+and once you're done:
+{{{
+ cd / &&
+ umount "$target"/boot &&
+ umount "$target" &&
+ kpartx -v -d "$dev_boot" &&
+ rmdir "$target"
+}}}
+
+Make sure that the filesystem isn't being mounted twice - i.e. never start the guest while the filesystems are mounted, and never mount them while the guest is running.