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--- soc:2009:pravin:journal:pxekniferomomatic [2009/06/04 06:22]
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+++ soc:2009:pravin:journal:pxekniferomomatic [2009/06/04 14:47] (current)
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-====== Pxeknife integretion with pxeknife ======
+====== Pxeknife integretion with rom-o-matic ======
@@ Line 5: / Line 5: @@
 provide pxe images/rom/nic with gpxe script embedded.  This script will connect to pxeknife server to get boot loader.
 ===== Implementation =====
+Actual working implementation is described [[PxeKnifeRomOMaticHTTP|here]]
+In file rom-o-matic/build.php the image is compiled by following command
+<code>
+make -C '$dir' '$target'
+</code>
+I have modified it to compile with embedded image by modifying above code with
+<code>
+make -C '$dir' EMBEDDED_IMAGE=./pxeDHCP.gpxe,./pxeSTATIC.gpxe '$target'
+</code>
+the script //./pxeDHCP.gpxe// contains following code
+<code>
+#!gpxe
+echo "Hi, We will be using PXEKnife from URL http://www.alien.doesntexist.org/pxeknife"
+echo "It is assumed that you have dhcp networking"
+imgload pxeSTATIC.gpxe
+imgstat
+ifopen net0
+echo "Hit Control+C to cancel DHCP"
+echo "You may want to do this if you want to use static-IP"
+echo "Otherwise, it will try DHCP, and then anyway go to static-IP"
+sleep 4
+dhcp net0
+set 209:string pxelinux.cfg/default
+set 210:string http://www.alien.doesntexist.org/pxeknife/
+echo "Here we go"
+chain http://www.alien.doesntexist.org/pxeknife/pxelinux.0
+echo "PxeKnife booting cancelled, using local disk instead.."
+</code>
+and //./pxeSTATIC.gpxe// contains following script.
+<code>
+#!gpxe
+echo "As you dont have DHCP, you need to give details about network configuration"
+echo "Soon, you will be presented with interface to provide details about network configuration"
+echo "Please provide, IP address, Netmask, Gateway and Router"
+ifopen net0
+set net0/ip 10.0.2.15
+set net0/netmask 255.255.255.0
+set net0/gateway 10.0.2.2
+set net0/dns 10.0.2.3
+sleep 3
+config
+set 209:string pxelinux.cfg/default
+set 210:string http://www.alien.doesntexist.org/pxeknife/
+echo "Here we go"
+chain http://www.alien.doesntexist.org/pxeknife/pxelinux.0
+echo "PxeKnife booting cancelled, using local disk instead.."
+</code>
+The code is hosted at url [[http://www.alien.doesntexist.org/pxeknife/PHP/gpxe_generation/]]
+===== Problems (solved) =====
+When I boot using qemu with following command
+<code>
+qemu -fda gpxe-git-e1000.dsk
+</code>
+I get following error
+<code>
+no such interface: net0
+</code>
+and booting fails :-(. I also tried with gpxe-git-3c509-eisa.dsk but same result.\\
+But when I compile the the gpxe with same script and no target, it works fine
+<code>
+make EMBEDDED_IMAGE=./pxeDHCP.gpxe
+qemu -fda bin/gpxe.dsk
+</code>
+==== Solution ====
+Problem was that, qemu does not support all network drivers, and you need to tell qemu which device driver to emulate.
+Following qemu command is working for rtl8139
+<code>
+qemu -fda gpxe-git-rtl8139.dsk -net nic,model=rtl8139 -net user
+</code>
+===== For static IP =====
+To support static IP, the plan is to have two scripts, one with DHCP and one with Static.
+When DHCP fails, static will pick up and continue execution.
+==== Problem (solved) ====
+Second script is not getting executed.
+I had to load the second script from first script using imgload
+<code>
+imgload pxeSTATIC.gpxe
+</code>
+Other than that,
+I had to comment out the break statement in //core/main.c// inside function //main()//
+there is a loop which iterate over each image. but there was a break, which had to be removed.
+<code>
+        if ( have_images() ) {
+            for_each_image ( image ) {
+                image_exec ( image );
+                /* break;  */ /* commented so that second script will be executed -- pravin */
+            }
+        } else {
+</code>
+Other change is done in //image/script.c// file inside function //script_exec()// where at end, it re-registers the script.
+The second executable does not get executed when this line is there, so, I commented it out.
+I am not sure what exactly is the problem, but my guess is that, \\
+re_register puts the script on top of the list, but older mapping where second script  was loaded in memory gets messed up somehow.
+<code>
+    rc = 0;
+ done:
+    /* Re-register image and return */
+    register_image ( image );    /* commented so that next one will be executed -- pravin */
+    return rc;
+}
+</code>