[Xen-users] Moved from Xen 2 to Xen 3... some questions..

["George Styles" <ripnetuk@xxxxxxxxx>]

Hi,

Ive been using Xen2 for ages, and it great, but ive decided to go to Xen 3.

Ive got it working, but I want to ask a couple of questions about it.

1. There no longer seems to be a seperate DomU and Dom0 built when I build from source. Is this the new policy? this would suit me, as I always used Xen0 kernels in my guest domains anyway.

2. Ive got me a vmx (vanderpool / intel virtualization tech) enabled processor (as shown in cpuflags in /proc/cpuinfo) - can Xen just use it from the default build (make world), or do I have to set any flags at compile time? it didnt winge about missing LibVNCServer, so I assume it wasnt built... ive looked in the manual, but it doesnt seem to say what I need to set to build a vmx version.

3. Still relating to VMX - how can I determine if my bios supports VMX? its a Compaq machine. Does the presence of vmx in /proc/cpuinfo indicate the bios supports it? there are no options in the BIOS about vmx (there is one about NX flag - i realise thats the no execute flag, but that is where I would expect any VMX options to be). Do all bios's that support VMX have an option to enbale / disable it?

If its not enabled, is is possible to 'hack' the bios image to enable it? (i once used a tool to enable IRDA on a bios for a gigabyte motherboard, so I know bios rom images can be tampered with!)

4. The processor in the new box is dual core- do I need to build a SMP version of the Xen hypervisor / Linux kernel to take advantage of this? or does the hypervisor deal with this side of things, and allocate processors to domains?

5. Is there ANY way to see the pre-linux-kernel messages from boot (the messages from the hypervisor)? they scroll past so quickly I cannot read them, then if I get a kernel panic when the Linux kernel starts, I cannot see what the hypervisor was saying. It turned out to be lack of sata drivers in the kernel (they were modules), but that was guesswork. Im sure the Xen boot messages would tell me what hardware it had picked up.

6. When I was trying to build a custom kernel (with the sata drivers in), i tried the usual
make ARCH=xen menuconfig
in the linux source dir, but it gave an error (something about no such target or somesuch).
Is this no longer nescesary? it worked OK when I ommitted the ARCH=xen, but I didnt proceed as I wasnt sure if it would compile in the Xen stuff... whats going on???

(I got it booting in the end by making a ramdisk, so these questions are academic, but I like to understand whats going on)

Finally, if the noreboot option is in the hypervisor parameter lines in grub config, does that prevent software reboot from working in Dom0? ive remotely crashed my Xen box on a reboot, and am hoping thats what it is! (it was its first reboot after booting Dom0 and I still had noreboot in from when I was trying to get Dom0 up)

thanks in advance for any insight :)

George
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users