From 301f556b09e6b04ad9312cc2d27517d7af2c6c66 Mon Sep 17 00:00:00 2001 From: Anatoli Babenia Date: Tue, 14 Aug 2018 14:00:08 +0800 Subject: [PATCH 1/2] Introduce PXE ROM gently PXE ROM is explained a little late, and I decided to simplify it --- pixiecore/README.booting.md | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/pixiecore/README.booting.md b/pixiecore/README.booting.md index decb2307..d10634f7 100644 --- a/pixiecore/README.booting.md +++ b/pixiecore/README.booting.md @@ -1,16 +1,19 @@ # How it works Pixiecore implements four different, but related protocols in one -binary, which together can take a PXE ROM from nothing to booting -Linux. They are: ProxyDHCP, PXE, TFTP, and HTTP. Let's walk through -the boot process for a PXE ROM. +binary, which together can take a network card to boot system into +Linux. They are: ProxyDHCP, PXE, TFTP, and HTTP. Let's +walk through the network boot process. ![Boot process](https://cdn.rawgit.com/google/netboot/master/pixiecore/bootgraph.svg) ## Step 1: DHCP/ProxyDHCP +Network boot is initiated by PXE ROM firmware that is embedded in +a capable network card. + The first thing a PXE ROM does is request a configuration through -DHCP, with some additional PXE options set to indicate that it wants +DHCP request with additional PXE options set to indicate that it wants to netboot. It expects a reply that mirrors some of these options, and includes boot instructions in addition to network configuration. From 656a2e416cb01b3a7a24f5cfac9aee4c90d0c8f9 Mon Sep 17 00:00:00 2001 From: Anatoli Babenia Date: Tue, 14 Aug 2018 14:50:03 +0800 Subject: [PATCH 2/2] Mention DHCPDISCOVER is iniitial request name And also explain what are PXE options exactly --- pixiecore/README.booting.md | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/pixiecore/README.booting.md b/pixiecore/README.booting.md index d10634f7..e4b643d0 100644 --- a/pixiecore/README.booting.md +++ b/pixiecore/README.booting.md @@ -14,7 +14,9 @@ a capable network card. The first thing a PXE ROM does is request a configuration through DHCP request with additional PXE options set to indicate that it wants -to netboot. It expects a reply that mirrors some of these options, and +to netboot (on a lower level it is `DHCPDISCOVER` with +[Option 60](https://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol#DHCP_client_vendor_identification)). +It expects a reply that mirrors some of these options, and includes boot instructions in addition to network configuration. The normal way of providing these options is to edit your DHCP