[Beowulf] PXE/TFTP and Xen Kernel Issues

[Jess Cannata]

Thanks Bernard! This is what I was looking for.

Jess

On 12/16/2009 07:13 PM, Bernard Li wrote:
> Hi Jess:
>
> With Xen-based kernels, you should be using the xen.gz "kernel"
> instead of vmlinuz.  Here's what a grub entry looks like for booting
> Xen-based kernels:
>
> title CentOS (2.6.18-164.el5xen)
> 	root (hd0,0)
> 	kernel /xen.gz-3.4.0
> 	module /vmlinuz-2.6.18-164.el5xen ro root=/dev/VolGroup00/LogVol00
> 	module /initrd-2.6.18-164.el5xen.img
>
> Good luck!
>
> Cheers,
>
> Bernard
>
> On Tue, Dec 15, 2009 at 2:22 PM, Jess Cannata<jac67 at georgetown.edu>  wrote:
>    
>> I'm having a problem booting Xen kernels via PXE. I want to boot a machine
>> via PXE that will then host Xen virtual machines. The client machine PXE
>> boots, receives the pxelinux.0 file, and then grabs the Xen kernel
>> (vmlinuz-2.6.18-164.6.1.el5xen). However, it can never load the Xen kernel.
>> On the client, I get the following error:
>>
>> Invalid or corrupt kernel image.
>>
>> I have tried the following three kernels (two stock Centos kernels and one
>> custom compiled kernel) and only the Xen kernel fails:
>>
>> -rw-r--r-- 1 root root 2030154 Dec 10 15:28 vmlinuz-2.6.18-164.6.1.el5xen
>> -rw-r--r-- 1 root root 1932284 Sep 25 16:17 vmlinuz-2.6.18-164.el5
>> -rw-r--r-- 1 root root 3277584 Dec 10 15:29 vmlinuz-2.6.27.15-jw-node
>>
>> The others load without error. I have checked multiple times that the Xen
>> kernel is not corrupt via md5sums and by booting it via grub. It just seems
>> not to like the PXE system. Here is a snippet of the dnsmasq log to show
>> that the file is sent correctly to the client:
>>
>> Dec 11 04:12:57 julie dnsmasq[9117]: TFTP sent /tftpboot/pxelinux.0 to
>> 192.168.0.6
>> Dec 11 04:12:57 julie dnsmasq[9117]: TFTP sent
>> /tftpboot/pxelinux.cfg/default to 192.168.0.6
>> Dec 11 04:12:57 julie dnsmasq[9117]: TFTP sent
>> /tftpboot/vmlinuz-2.6.18-164.6.1.el5xen to 192.168.0.6
>>
>> I have tried three different systems for the DHCP, TFTP, and PXE Servers
>> (using stock RHEL/Centos packages). Here are the specs:
>>
>> System 1
>> Centos 5.4 (64-bit) with nvidia Ethernet adapters
>> dnsmasq for both DHCP and TFTP Servers
>> syslinux for PXE
>>
>> System 2
>> Centos 5.4 (64-bit) with e1000 Ethernet adapters
>> dnsmasq for both DHCP and TFTP Servers
>> syslinux for PXE
>>
>> System 3
>> Centos 5.3 (32-bit) with e1000 Ethernet adapters (trying 32-bit version of
>> the Xen kernel)
>> Config One:
>> dnsmasq for both DHCP and TFTP Servers
>> syslinux for PXE
>>
>> Config Two:
>> dnsmasq for DHCP Server
>> tftp-server for TFTP Server
>> syslinux for PXE
>>
>> The client machines use the same hardware as the servers. I haven't seen
>> anything about Xen kernels having issues with PXE. Before I start trying
>> different flavors of Linux, I'm curious if anyone else has seen or heard of
>> this problem.
>>
>> Many thanks in advance.
>>
>> Jess
>> _______________________________________________
>> Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
>> To change your subscription (digest mode or unsubscribe) visit
>> http://www.beowulf.org/mailman/listinfo/beowulf
>>
>>