Re: [Xen-users] Xen & DRBD

Stuart Poulton
2008-03-18T08:20:29Z

Hi,

I''ve just tried again, this time using one of the example xen files.
Details below.


x-host-3:/etc/xen/vm # cat test
# This is a bootloader used to boot paravirtualized domains.  You can optionally
# plug in a different boot loader here, e.g., pygrub.  There is usually no
# reason to change this.  Don''t explicitly specify kernel and ramdisk
if you use
# a bootloader.
bootloader="/usr/lib/xen/boot/domUloader.py"

# The domUloader will pull the specified kernel and initrd out of the
domU''s
# disk, and use that to boot.  This is easier to manage, compared to manually
# keeping a copy of the kernel and initrd in sync in dom0''s filesystem
and
# pointing to them with the "kernel" and "ramdisk"
parameters.  Syntax is
# "VDEV:KERNEL,INITRD", where VDEV is the block device (from
domU''s point of
# view) within which KERNEL and INITRD can be found.
bootentry = "hda1:/boot/vmlinuz-xen,/boot/initrd-xen"


# Remaining settings for the example VM:
name="domUloader-example"
memory=512
vcpus=1
on_crash="destroy"
on_poweroff="destroy"
on_reboot="restart"
localtime=0
builder="linux"
bootargs="--entry=xvda1:/boot/vmlinuz-xen,/boot/initrd-xen"
disk=[ ''drbd:xendomains,xvda,w'' ]
vif=[ ''mac=00:16:3e:00:01:02,bridge=xenbr0'' ]
vfb=[''type=vnc,vncunused=1'']


x-host-3:/etc/xen/vm # cat /proc/drbd
version: 8.0.6 (api:86/proto:86)
SVN Revision: 3048 build by phil@mescal, 2007-09-03 10:39:27
 0: cs:Connected st:Primary/Primary ds:UpToDate/UpToDate C r---
    ns:0 nr:1052672 dw:1052672 dr:0 al:0 bm:284 lo:0 pe:0 ua:0 ap:0
        resync: used:0/31 hits:65650 misses:142 starving:0 dirty:0
changed:142
        act_log: used:0/257 hits:0 misses:0 starving:0 dirty:0 changed:0
x-host-3:/etc/xen/vm # drbdadm state xendomains
Primary/Primary


x-host-3:/etc/xen/vm # xm create -c test
Using config file "./test".
Error: Disk isn''t accessible


x-host-3:/etc/xen/vm # xm create -n opensuse-1
Using config file "./opensuse-1".
(vm
    (name opensuse-1)
    (memory 384)
    (on_poweroff destroy)
    (on_reboot restart)
    (on_crash destroy)
    (vcpus 1)
    (on_xend_start ignore)
    (on_xend_stop ignore)
    (uuid 7bf59311-0304-d34e-09a7-4d2f2fa5f5e9)
    (bootloader /usr/lib/xen/boot/domUloader.py)
    (bootloader_args
''--entry=xvda1:/boot/vmlinuz-xen,/boot/initrd-xen'')
    (image (linux (args '' '')))
    (device (vbd (uname drbd:drdb0) (dev xvda) (mode w)))
    (device (vbd (uname phy:/dev/cdrom) (dev xvdb:cdrom) (mode r)))
    (device (vif (mac 00:16:3e:19:69:48)))
    (device (vkbd))
    (device
        (vfb
            (vncunused 1)
            (type vnc)
            (display localhost:10.0)
            (xauthority /root/.Xauthority)
        )
    )
)



On Mon, 2008-03-17 at 19:28 +0000, Gareth Bult wrote:
> Hi,
>
> When you switch to "drbd:" you need to change the path to the
drbd resource name, rather than the device name. So if you have a drbd.conf that
says;
>
> resource fred {
>    on nodea {
>        device /dev/drbd0;
>
> You would use;
> disk=[ ''drbd0:fred,xvda,w'',]
>
> hth
> Gareth.
>
>
> ----- Original Message -----
> From: "Stuart Poulton" <swp@astro.le.ac.uk>
> To: xen-users@lists.xensource.com
> Sent: Monday, March 17, 2008 3:08:47 PM GMT +00:00 GMT Britain, Ireland,
Portugal
> Subject: [Xen-users] Xen & DRBD
>
> Dear All,
>
> I''m using drbd to provide a HA pair of servers to run xen domains
on.
>
> I''ve created a test domain as follows
>
> x-host-2:~ # more /etc/xen/vm/opensuse
> name="opensuse"
> ostype="opensuse"
> uuid="ee62226a-8487-cc02-d89f-dafafd1f35e6"
> memory=1214
> vcpus=2
> on_crash="destroy"
> on_poweroff="destroy"
> on_reboot="restart"
> localtime=0
> builder="linux"
> bootloader="/usr/lib/xen/boot/domUloader.py"
> bootargs="--entry=xvda1:/boot/vmlinuz-xen,/boot/initrd-xen"
> extra=" "
> disk=[ ''phy:/dev/drbd0,xvda,w'',]
> vif=[ ''mac=00:16:3e:29:fb:80'', ]
> vfb=[''type=vnc,vncunused=1'']
>
> This works fine, and start and stop the domain on both of the nodes.
> However if I try to use
>
> disk=[ ''drbd:xendomains,xvda,w'',]
>
> I get the following error....
>
> x-host-2:~ # xm create opensuse
> Using config file "/etc/xen/vm/opensuse".
> Error: Disk isn''t accessible
>
> I''m expecting the block-drbd script to do something here, but from
what
> I can tell it''s not.
>
> I suspect I''ve missed something fundamental. Any pointers please ?
>
> Thanks
>
> Stuart