running gentoo on xen 4.1 and linux 3

[nivw]

well, I am used to gentoo but very new to xen.
I am seeking to run the hypervisor(dom0) using minimal gentoo setup, and create two guest os(domU).
one domU for my testing of new software , and the other in case the first dies.
I tried most guides on the web and found some missing points. as I still can't use domU after three weeks, i want to note some issues and later may publish a current howto.
1. xvda - when installing the domU one must use xvda instead of sda1. this appies to the xen config file, and the /etc/fstab file.
2. use genkernel to create a kernel for your domU. I couldnt boot without it
3. in the domU file system , edit /etc/inittab and change:
# SERIAL CONSOLES
s0respawn:/sbin/agetty 9600 hvc0 vt100

but I boot in to a read only file system

Initializing cgroup subsys cpuset
Linux version 3.0.0-rc5 (root@mojhito) (gcc version 4.4.5 (Gentoo 4.4.5 p1.2, pie-0.4.5) ) #1 SMP Thu Jul 14 19:09:04 IDT 2011
Command line: root=/dev/xvda ro
ACPI in unprivileged domain disabled
released 0 pages of unused memory
Set 0 page(s) to 1-1 mapping.
BIOS-provided physical RAM map:
Xen: 0000000000000000 - 00000000000a0000 (usable)
Xen: 00000000000a0000 - 0000000000100000 (reserved)
Xen: 0000000000100000 - 0000000020800000 (usable)
NX (Execute Disable) protection: active
DMI not present or invalid.
e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
e820 remove range: 00000000000a0000 - 0000000000100000 (usable)
No AGP bridge found
last_pfn = 0x20800 max_arch_pfn = 0x400000000
initial memory mapped : 0 - 0244f000
Base memory trampoline at [ffff88000009b000] 9b000 size 20480
init_memory_mapping: 0000000000000000-0000000020800000
0000000000 - 0020800000 page 4k
kernel direct mapping tables up to 20800000 @ 1fefa000-20000000
xen: setting RW the range 1ffe6000 - 20000000
RAMDISK: 0189a000 - 0244f000
.
.
.
e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
e1000: Copyright (c) 1999-2006 Intel Corporation.
Loading iSCSI transport class v2.0-870.
EXT3-fs (xvda): error: couldn't mount because of unsupported optional features (240)
EXT2-fs (xvda): error: couldn't mount because of unsupported optional features (240)
EXT4-fs (xvda): mounted filesystem with ordered data mode. Opts: (null)
udev: starting version 151
udevd (15522): /proc/15522/oom_adj is deprecated, please use /proc/15522/oom_score_adj instead.
input: PC Speaker as /devices/platform/pcspkr/input/input0
blkfront: barrier: empty write xvda op failed
blkfront: xvda: barrier or flush: disabled
EXT4-fs (xvda): re-mounted. Opts: (null)

[CaptainBlood]

Hi,

I have no idea how to succeed with XEN - Kernel 3.0.
I understand you are attempting with domU installed on a real partition.
According to XEN wiki access to real partition is something very new ...
I guess only few have proper knowledge how to solve such an issue, if any ...

If you are really new to XEN I can only recommend you start with the previous kernel (2.36.34-xx if I remember correctly)
Although I may not be sparing CPU as much as the latest, as well as requiring two kernel configuration ( dom0 + domU),
I can assure it is stable, mature and full featured.

Once you have achieved such a configuration, you can pursue with trying to configure a 3.0 kernel for each side.

Hope this can help.

Thanks for your attention

[meyerm]

Are you using a pvops-setup? I just tried to switch to kernel-3.0 and xen-4.1 and am even too stupid to get my xend running with this new kernel again

Code: Select all

dantooine ~ # /etc/init.d/xend start
 * Starting xenstored daemon ...
xc: error: Could not obtain handle on privileged command interface (2 = No such file or directory): Internal error
FATAL: Failed to open connection to hypervisor: No such file or directory


 * Setting domain0 name record
xenstore-write: xs_open: No such file or directory                                           [ ok ]
 * Starting xenconsoled daemon ...                                                           [ ok ]
 * Can't start xend - this is not a privileged domain.
 * ERROR: xend failed to start
dantooine ~ # 

Code: Select all

dantooine ~ # ls -l /dev/xen*
crw-rw---- 1 root root 10, 62 Jul 29 23:21 /dev/xen!evtchn
crw-rw---- 1 root root 10, 60 Jul 29 23:21 /dev/xen!gntalloc
crw-rw---- 1 root root 10, 61 Jul 29 23:21 /dev/xen!gntdev

/dev/xen:
total 0
crw------- 1 root root 10, 62 Jul 29 23:21 evtchn
crw------- 1 root root 10, 60 Jul 29 23:21 gntalloc
crw------- 1 root root 10, 61 Jul 29 23:21 gntdev
dantooine ~ #

M

[meyerm]

OK, at least the afore mentioned problem of mine has been solved. I need to activate the legacy /proc/xen-compatibility. Then it starts... now let's see if I hit the same problems you mentioned.