RE: [BProc] Red Hat PXE fixes for Clustermatic 3

[MIYOSHI,DENNIS (HP-Loveland,ex1) <den...@hp...>]

I actually got the RedHat 9.0 TFTP server to work with PXE.  I start this
with the supplied service definition in /etc/xinetd.d.  I also used the
RedHat 9.0 DHCP supplied RPM.
 
Best regards,
 
Dennis E. Miyoshi, PE
Hendrix Release Manager
Hewlett-Packard Company
825 14th Street, S.W.,  MS E-200
Loveland, CO  80537
(970) 898-6110

-----Original Message-----
From: bpr...@li...
[mailto:bpr...@li...] On Behalf Of Larry Baker
Sent: Friday, October 24, 2003 11:33 AM
To: bpr...@li...
Subject: [BProc] Red Hat PXE fixes for Clustermatic 3


My system is a 4 node Linux Beowulf cluster, using the Clustermatic 3 kit.
I was not able to get the PXE package that came with Red Hat 8.0 to work
(pxe-0.1-33).  I tried the newer version that comes with Red Hat 9
(pxe-0.1-36), but it would not work either.
 
I downloaded the source RPMS for the two versions, and found they were
almost identical.  So, I modified the Red Hat 9 PXE package.  The changes I
made are:
 
1.  The PXE package includes a multicast TFTP server, /usr/sbin/in.mtftpd.
However, it does not include a service definition file for mtftp in
/etc/xinetd.d.  I fixed that.
 
Note: On Red Hat 8 you still have to manually edit /etc/services to add
entries for pxe and mtftp.  They are already there in Red Hat 9.
 
2.  The linux.0 layer 0 bootstrap sets up the downloaded initrd ram disk as
/dev/ram1 (0x0101), but it is mounted on /dev/ram0 (0x0100).  Without a
kernel command line "root=/dev/ram0" to override it, the boot fails.  I
changed the code in prepare.c to set up the ram disk as /dev/ram0.
 
3.  By default, pxe-0.1-33 redirects the console to COM1; pxe-0.1-36 does
not.  The default kernel command line is hard-coded into linux.0.  To
override it, you must manually enter a replacement at the console.  I
modified linux.c and download.c to add an optional layer 3 file containing
the default kernel command line (like the APPEND option in
syslinux/pxelinux).  Unfortunately, PXE can select only one default
kernel/initrd/command line combination.  This is not a problem for me, since
I have a small, homogeneous cluster.
 
Installation instructions are in the HTML file, pxe-0.1-36a.htm.
 

Larry Baker
US Geological Survey
ba...@us... <mailto:ba...@us...>