[arch-releng] [RFC] [PATCH] [archiso] README: add: alternative boot methods

[Gerardo Exequiel Pozzi]

Signed-off-by: Gerardo Exequiel Pozzi <vmlinuz386 at yahoo.com.ar>
---
 README |  114 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 114 insertions(+)

diff --git a/README b/README
index 5f1d253..a59d524 100644
--- a/README
+++ b/README
@@ -16,6 +16,13 @@ INDEX
     * PC-BIOS (MBR)
     * PC-BIOS (ISOHYBRID-MBR)
     * PC-EFI (GPT) [x86_64 only]
+* Alternative boot methods (configs/releng)
+  * ISO in loopback mode
+  * ISO in memdisk mode
+  * Network booting (PXE) [first stage]
+    * DHCP + TFTP
+    * DHCP + HTTP
+    * HTTP/NFS/NBD [second stage]
 * Build requirements
 * Image types generated by mkarchiso.
 * File format for aitab.
@@ -273,6 +280,113 @@ Note: Using here a GPT partition mode as example, but MBR should also works
 
 
 
+*** Alternative boot methods (configs/releng)
+
+** ISO in loopback mode.
+
+Note: Described method is for using with GRUB2.
+      GRUB2 is installed on target media and archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso
+      is at path <TARGET-PATH> on disk <D> and partition <P>,
+      where filesystem is labeled as <TARGET-FS-LABEL>.
+
+menuentry "Arch Linux (x86_64)" {
+    set isofile="/<TARGET-PATH>/archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso"
+    loopback loop (hd<D>,<P>)$isofile
+    linux (loop)/arch/boot/x86_64/vmlinuz archisolabel=<FS-LABEL> img_label=<TARGET-FS-LABEL> img_loop=$isofile
+    initrd (loop)/arch/boot/x86_64/archiso.img
+}
+
+menuentry "Arch Linux (i686)" {
+    set isofile="/<TARGET-PATH>/archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso"
+    loopback loop (hd<D>,<P>)$isofile
+    linux (loop)/arch/boot/i686/vmlinuz archisolabel=<FS-LABEL> img_label=<TARGET-FS-LABEL> img_loop=$isofile
+    initrd (loop)/arch/boot/i686/archiso.img
+}
+
+
+** ISO in memdisk mode.
+
+Note: Described method is for using with SYSLINUX. Anyway MEMDISK from SYSLINUX can work
+      with other bootloaders.
+      SYSLINUX is installed on target media and archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso
+      is at path <TARGET-PATH>.
+      On 32-bit systems, is needed to pass vmalloc=nnM to the kernel, where nn is the size
+      of the ISO image plus 64 MiB (or 128 MiB).
+
+
+LABEL arch_x64
+   LINUX memdisk
+   INITRD /<TARGET-PATH>/archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso
+   APPEND iso
+
+LABEL arch_x32
+   LINUX memdisk
+   INITRD /<TARGET-PATH>/archlinux-<YYYY>.<MM>.<DD>-<TYPE>-<ARCH>.iso
+   APPEND iso
+
+
+** Network booting (PXE).
+
+All ISOs are ready to act as PXE server, some manual steps are needed
+to setup desired PXE boot mode.
+Alternativelly is possible to use an already PXE server following the same logic.
+Note: Setup network first, adjust IP adresses, and respect all slashes "/".
+
+First stage is for loading kernel and initramfs via PXE, two methods described here:
+
+* DHCP + TFTP
+
+Note: All NIC firmwares should support this.
+
+# dnsmasq --port=0 \
+          --enable-tftp \
+          --tftp-root=/run/archiso/bootmnt \
+          --dhcp-range=192.168.0.2,192.168.0.254,86400 \
+          --dhcp-boot=/arch/boot/syslinux/gpxelinux.0 \
+          --dhcp-option-force=209,boot/syslinux/archiso.cfg \
+          --dhcp-option-force=210,/arch/
+
+* DHCP + HTTP
+
+Note: Not all NIC firmware supports HTTP and DNS (if domain name is used).
+      At least this works with iPXE and gPXE.
+
+# dnsmasq --port=0 \
+          --dhcp-range=192.168.0.2,192.168.0.254,86400 \
+          --dhcp-boot=http://192.168.0.7/arch/boot/syslinux/gpxelinux.0 \
+          --dhcp-option-force=209,boot/syslinux/archiso.cfg \
+          --dhcp-option-force=210,http://192.168.0.7/arch/
+
+
+Once kernel is started from PXE, SquashFS files and other misc files
+inside "arch" directory must be loaded (second stage). One of the follow
+methods can be used to serve the rest of live-medium.
+
+* HTTP
+
+# darkhttpd /run/archiso/bootmnt
+
+
+* NFS
+
+# echo "/run/archiso/bootmnt 192.168.0.*(ro,no_subtree_check,no_root_squash)" >> /etc/exports
+# rc.d start rpcbind nfs-common nfs-server
+
+
+* NBD
+
+Note: Adjust ARCH_201204 as needed.
+
+# cat << EOF > /tmp/nbd-server.conf
+[generic]
+[archiso]
+    readonly = true
+    exportname = /dev/disk/by-label/ARCH_201204
+EOF
+# nbd-server -C /tmp/nbd-server.conf
+
+
+
 *** Build requirements
 
 ** For mkarchiso script needs these packages (build host):
-- 
1.7.9.6