[PATCH] xend: drbd improvements

[PATCH] xend: drbd improvements

[Jim Fehlig]

# HG changeset patch
# User Jim Fehlig <jfehlig@novell.com>
# Date 1289324668 25200
# Node ID fb0498c0cbdd6be20bbcb5560779ad6f380fe9e8
# Parent  985f5fa8fc59f84c8577c482df6246258c785991
xend: drbd improvements

1) drbdadm state is debrecated, and the script tries to detect the
primary/secondary information from the deprecated message
2) os.popen2 does not work with the array as argument
3) popen2 is deprecated since python2.6

Re: http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1685

    From: Berthold Gunreben <bg@suse.de>
    Signed-off-by: Jim Fehlig <jfehlig@novell.com>

diff -r 985f5fa8fc59 -r fb0498c0cbdd tools/python/xen/xend/XendDomainInfo.py
--- a/tools/python/xen/xend/XendDomainInfo.py	Mon Nov 08 17:25:54 2010 +0000
+++ b/tools/python/xen/xend/XendDomainInfo.py	Tue Nov 09 10:44:28 2010 -0700
@@ -35,6 +35,7 @@
 import shutil
 import traceback
 from types import StringTypes
+from subprocess import *
 
 import xen.lowlevel.xc
 from xen.util import asserts, auxbin, mkdir
@@ -3254,7 +3255,9 @@
             if disk.find(":") != -1:
                 (disktype, diskname) = disk.split(':', 1)
                 if disktype == 'drbd':
-                    (drbdadmstdin, drbdadmstdout) = os.popen2(["/sbin/drbdadm", "state", diskname])
+                    p = Popen(["/sbin/drbdadm", "role", diskname],
+                              stdin=PIPE, stdout=PIPE, close_fds=True )
+                    (drbdadmstdin, drbdadmstdout) = (p.stdin, p.stdout)
                     (state, junk) = drbdadmstdout.readline().split('/', 1)
                     if state == 'Secondary':
                         os.system('/sbin/drbdadm primary ' + diskname)

Re: [PATCH] xend: drbd improvements

[Ian Jackson]

Jim Fehlig writes ("[Xen-devel] [PATCH] xend: drbd improvements"):
> xend: drbd improvements
> 
> 1) drbdadm state is debrecated, and the script tries to detect the
> primary/secondary information from the deprecated message
> 2) os.popen2 does not work with the array as argument
> 3) popen2 is deprecated since python2.6

Forgive my ignorance, but: why does xend need to mess with drbd at
all ?  Why can't it just open the block device ?

xl and libxl don't have any drbd functionality so if this is necessary
it's a missing feature.

Ian.

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Ian Jackson wrote:
> Jim Fehlig writes ("[Xen-devel] [PATCH] xend: drbd improvements"):
>   
>> xend: drbd improvements
>>
>> 1) drbdadm state is debrecated, and the script tries to detect the
>> primary/secondary information from the deprecated message
>> 2) os.popen2 does not work with the array as argument
>> 3) popen2 is deprecated since python2.6
>>     
>
> Forgive my ignorance, but: why does xend need to mess with drbd at
> all ?  Why can't it just open the block device ?
>   

Good question.  I too was surprised to see special casing of drbd within
xend.  Seems c/s 20158 added this code to allow bootloaders (pygrub,
domUloader, et. al.) to work with drbd devices using the 'drbd:resource'
syntax.  Perhaps the author of that patch (cc'd) can provide more
details.  This patch simply makes improvements to the existing code. 
BTW, c/s 20158 also uses popen2() in tools/python/xen/util/blkif.py, so
IMO a V2 will be needed if this patch is considered.

> xl and libxl don't have any drbd functionality so if this is necessary
> it's a missing feature.
>   

Micheal, does xl/libxl need this functionality?

Regards,
Jim

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Jim Fehlig wrote:
> Ian Jackson wrote:
>   
>> Jim Fehlig writes ("[Xen-devel] [PATCH] xend: drbd improvements"):
>>   
>>     
>>> xend: drbd improvements
>>>
>>> 1) drbdadm state is debrecated, and the script tries to detect the
>>> primary/secondary information from the deprecated message
>>> 2) os.popen2 does not work with the array as argument
>>> 3) popen2 is deprecated since python2.6
>>>     
>>>       
>> Forgive my ignorance, but: why does xend need to mess with drbd at
>> all ?  Why can't it just open the block device ?
>>   
>>     
>
> Good question.  I too was surprised to see special casing of drbd within
> xend.  Seems c/s 20158 added this code to allow bootloaders (pygrub,
> domUloader, et. al.) to work with drbd devices using the 'drbd:resource'
> syntax.  Perhaps the author of that patch (cc'd) can provide more
> details.

The patch author's mail address is no longer valid, so we won't be
receiving any feedback from him :-(.

Regards,
Jim

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Jim Fehlig wrote:
> Jim Fehlig wrote:
>   
>> Ian Jackson wrote:
>>   
>>     
>>> Jim Fehlig writes ("[Xen-devel] [PATCH] xend: drbd improvements"):
>>>   
>>>     
>>>       
>>>> xend: drbd improvements
>>>>
>>>> 1) drbdadm state is debrecated, and the script tries to detect the
>>>> primary/secondary information from the deprecated message
>>>> 2) os.popen2 does not work with the array as argument
>>>> 3) popen2 is deprecated since python2.6
>>>>     
>>>>       
>>>>         
>>> Forgive my ignorance, but: why does xend need to mess with drbd at
>>> all ?  Why can't it just open the block device ?
>>>   
>>>     
>>>       
>> Good question.  I too was surprised to see special casing of drbd within
>> xend.  Seems c/s 20158 added this code to allow bootloaders (pygrub,
>> domUloader, et. al.) to work with drbd devices using the 'drbd:resource'
>> syntax.  Perhaps the author of that patch (cc'd) can provide more
>> details.
>>     
>
> The patch author's mail address is no longer valid, so we won't be
> receiving any feedback from him :-(.
>   

Sorry for the delay here, but I finally got around to investigating this
further.  As it turns out, drbd's block-drbd script handles all of the
details that c/s 20158 introduces within xend :-(.  IMO, this c/s should
be reverted as it causes a regression.  I've tested drbd without this
changeset and it works fine.

Regards,
Jim

Re: [PATCH] xend: drbd improvements

[Shriram Rajagopalan]

According to the block-drbd script's comments, live migration with
DRBD based disks
require dual primary setup and the block-drbd script automatically handles
 "changing the target host's vm disk to primary" when live migration
is initiated.

Removing drbd support from xend would necessitate an external agent to
actually promote the guest disk in target host to primary mode.

shriram


On Thu, Dec 16, 2010 at 4:45 PM, Jim Fehlig <jfehlig@novell.com> wrote:
> Jim Fehlig wrote:
>> Jim Fehlig wrote:
>>
>>> Ian Jackson wrote:
>>>
>>>
>>>> Jim Fehlig writes ("[Xen-devel] [PATCH] xend: drbd improvements"):
>>>>
>>>>
>>>>
>>>>> xend: drbd improvements
>>>>>
>>>>> 1) drbdadm state is debrecated, and the script tries to detect the
>>>>> primary/secondary information from the deprecated message
>>>>> 2) os.popen2 does not work with the array as argument
>>>>> 3) popen2 is deprecated since python2.6
>>>>>
>>>>>
>>>>>
>>>> Forgive my ignorance, but: why does xend need to mess with drbd at
>>>> all ?  Why can't it just open the block device ?
>>>>
>>>>
>>>>
>>> Good question.  I too was surprised to see special casing of drbd within
>>> xend.  Seems c/s 20158 added this code to allow bootloaders (pygrub,
>>> domUloader, et. al.) to work with drbd devices using the 'drbd:resource'
>>> syntax.  Perhaps the author of that patch (cc'd) can provide more
>>> details.
>>>
>>
>> The patch author's mail address is no longer valid, so we won't be
>> receiving any feedback from him :-(.
>>
>
> Sorry for the delay here, but I finally got around to investigating this
> further.  As it turns out, drbd's block-drbd script handles all of the
> details that c/s 20158 introduces within xend :-(.  IMO, this c/s should
> be reverted as it causes a regression.  I've tested drbd without this
> changeset and it works fine.
>
> Regards,
> Jim
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel
>



-- 
perception is but an offspring of its own self

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Shriram Rajagopalan wrote:
> According to the block-drbd script's comments, live migration with
> DRBD based disks
> require dual primary setup and the block-drbd script automatically handles
>  "changing the target host's vm disk to primary" when live migration
> is initiated.
>
> Removing drbd support from xend would necessitate an external agent to
> actually promote the guest disk in target host to primary mode.
>   

Reverting c/s 20158 does not remove drbd support in xen.  On the
contrary, it fixes the use of drbd as documented here

http://www.drbd.org/users-guide/s-xen-configure-domu.html

The drbd project provides block-drbd.  I'm not talking about removing
it.  I'm talking about removing a hack in xend that prevents even using
drbd resource type.

Regards,
Jim

Re: [PATCH] xend: drbd improvements

[Ian Jackson]

Jim Fehlig writes ("Re: [Xen-devel] [PATCH] xend: drbd improvements"):
> Sorry for the delay here, but I finally got around to investigating this
> further.  As it turns out, drbd's block-drbd script handles all of the
> details that c/s 20158 introduces within xend :-(.  IMO, this c/s should
> be reverted as it causes a regression.  I've tested drbd without this
> changeset and it works fine.

Thanks for looking into this and testing things.  I have reverted
20158 from xen-unstable.

Ian.

Re: [PATCH] xend: drbd improvements

[Shriram Rajagopalan]

I was just looking over the patch on blkif.py and I believe there is a bug.
--- a/tools/python/xen/util/blkif.py	Fri Dec 10 18:08:19 2010 +0000
+++ b/tools/python/xen/util/blkif.py	Wed Jan 05 23:31:24 2011 +0000
@@ -71,15 +71,8 @@ def _parse_uname(uname):
     if uname.find(":") != -1:
         (typ, fn) = uname.split(":", 1)

-        if typ == "phy" and not fn.startswith("/"):
+        if typ in ("phy", "drbd") and not fn.startswith("/"):
             fn = "/dev/%s" %(fn,)
-
-        if typ == "drbd":
-            if not fn.startswith("drbd"):
-                (drbdadmstdin, drbdadmstdout) =
os.popen2(["/sbin/drbdadm", "sh-dev", fn])
-                fn = drbdadmstdout.readline().strip()
-            else:
-                fn = "/dev/%s" %(fn,)

         if typ in ("tap", "tap2"):
             (taptype, fn) = fn.split(":", 1


 When you specify a drbd disk for a domU, its format is
  drbd:<resourceName>
wherein drbd expects a resource file in /etc/drbd.d/resourceName.res, that
contains the actual drbd device name (/dev/drbd1 or something).
 drbd does not export resources as devices in the /dev/ path (as is
the assumption
in the above patch). It actually exports them under /dev/drbd/by-res/.
Atleast thats
the case in my Debian box, with drbd 8.3.9

I can send out a patch if you folks agree with this.

shriram

On Wed, Jan 5, 2011 at 3:32 PM, Ian Jackson <Ian.Jackson@eu.citrix.com> wrote:
>
> Jim Fehlig writes ("Re: [Xen-devel] [PATCH] xend: drbd improvements"):
> > Sorry for the delay here, but I finally got around to investigating this
> > further.  As it turns out, drbd's block-drbd script handles all of the
> > details that c/s 20158 introduces within xend :-(.  IMO, this c/s should
> > be reverted as it causes a regression.  I've tested drbd without this
> > changeset and it works fine.
>
> Thanks for looking into this and testing things.  I have reverted
> 20158 from xen-unstable.
>
> Ian.
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel



--
perception is but an offspring of its own self

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

[-- Attachment #1: Type: text/plain, Size: 1487 bytes --]

Shriram Rajagopalan wrote:
> I was just looking over the patch on blkif.py and I believe there is a bug.
> --- a/tools/python/xen/util/blkif.py	Fri Dec 10 18:08:19 2010 +0000
> +++ b/tools/python/xen/util/blkif.py	Wed Jan 05 23:31:24 2011 +0000
> @@ -71,15 +71,8 @@ def _parse_uname(uname):
>      if uname.find(":") != -1:
>          (typ, fn) = uname.split(":", 1)
>
> -        if typ == "phy" and not fn.startswith("/"):
> +        if typ in ("phy", "drbd") and not fn.startswith("/"):
>              fn = "/dev/%s" %(fn,)
> -
> -        if typ == "drbd":
> -            if not fn.startswith("drbd"):
> -                (drbdadmstdin, drbdadmstdout) =
> os.popen2(["/sbin/drbdadm", "sh-dev", fn])
> -                fn = drbdadmstdout.readline().strip()
> -            else:
> -                fn = "/dev/%s" %(fn,)
>
>          if typ in ("tap", "tap2"):
>              (taptype, fn) = fn.split(":", 1
>
>
>  When you specify a drbd disk for a domU, its format is
>   drbd:<resourceName>
>   

Correct.  Sadly, I forgot I was testing on SLES, which contains local
xend patches to fix problems wrt external block scripts.  One of the
patches has existed for ages, before many of us were working on xen
:-).  I would really like to get these changes upstream, even though
xend is dying.  The first patch is a revert of
http://xenbits.xensource.com/xen-unstable.hg?rev/152257350930.  The
second patch, which I've rebased against -unstable, is attached.  Can
you test it?

Thanks,
Jim



[-- Attachment #2: xend-bootloader.patch --]
[-- Type: text/x-diff, Size: 3371 bytes --]

# HG changeset patch
# User Jim Fehlig <jfehlig@novell.com>
# Date 1294700641 25200
# Node ID c6c50a9ecd4f2f5088f63a19c2de99020bd80139
# Parent  7b4c82f07281ad9c48b652e2a305a7be607c5283
xend: improve psudeo-bootloader support for external block scripts

Userspace tools support external block scripts (e.g. block-drbd
provided by drbd project).  The psuedo-bootloader setup code in
xend has a few limitations wrt external block scripts, which this
patch addresses.

blkif.py: parse_uname() utility function should be able to parse a
disk specifier understood by the rest of the tools.

XendDomainInfo.py: Block devices using external block scripts must
be attached to dom0 before running the psuedo-bootloader.

    Signed-off-by: Jim Fehlig <jfehlig@novell.com>

diff -r 7b4c82f07281 -r c6c50a9ecd4f tools/python/xen/util/blkif.py
--- a/tools/python/xen/util/blkif.py	Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/python/xen/util/blkif.py	Mon Jan 10 16:04:01 2011 -0700
@@ -66,8 +66,8 @@
                 'type'         : 'Disk' }
     return val
 
-def _parse_uname(uname):
-    fn = taptype = None
+def parse_uname(uname):
+    fn = typ = taptype = None
     if uname.find(":") != -1:
         (typ, fn) = uname.split(":", 1)
 
@@ -76,15 +76,18 @@
                
         if typ in ("tap", "tap2"):
             (taptype, fn) = fn.split(":", 1)
-    return (fn, taptype)
+            if taptype in ("tapdisk", "ioemu"):
+                (taptype, fn) = fn.split(":", 1)
+    return (fn, (typ,taptype))
+
 
 def blkdev_uname_to_file(uname):
     """Take a blkdev uname and return the corresponding filename."""
-    return _parse_uname(uname)[0]
+    return parse_uname(uname)[0]
 
 def blkdev_uname_to_taptype(uname):
     """Take a blkdev uname and return the blktap type."""
-    return _parse_uname(uname)[1]
+    return parse_uname(uname)[1]
 
 def mount_mode(name):
     mode = None
diff -r 7b4c82f07281 -r c6c50a9ecd4f tools/python/xen/xend/XendDomainInfo.py
--- a/tools/python/xen/xend/XendDomainInfo.py	Wed Jan 05 23:54:15 2011 +0000
+++ b/tools/python/xen/xend/XendDomainInfo.py	Mon Jan 10 16:04:01 2011 -0700
@@ -38,7 +38,7 @@
 
 import xen.lowlevel.xc
 from xen.util import asserts, auxbin, mkdir
-from xen.util.blkif import blkdev_uname_to_file, blkdev_uname_to_taptype
+from xen.util.blkif import parse_uname
 import xen.util.xsm.xsm as security
 from xen.util import xsconstants
 from xen.util import mkdir
@@ -3248,9 +3248,18 @@
             devtype = devinfo[0]
             disk = devinfo[1]['uname']
 
-            fn = blkdev_uname_to_file(disk)
-            taptype = blkdev_uname_to_taptype(disk)
-            mounted = devtype in ['tap', 'tap2'] and taptype != 'aio' and taptype != 'sync' and not os.stat(fn).st_rdev
+            (fn, types) = parse_uname(disk)
+            def _shouldMount(types):
+                if types[0] in ('file', 'phy'):
+                    return False
+                if types[0] in ('tap', 'tap2'):
+                    if types[1] in ('aio', 'sync'):
+                        return False
+                    else:
+                        return True
+                return os.access('/etc/xen/scripts/block-%s' % types[0], os.X_OK)
+
+            mounted = _shouldMount(types)
             mounted_vbd_uuid = 0
             if mounted:
                 # This is a file, not a device.  pygrub can cope with a

[-- Attachment #3: Type: text/plain, Size: 138 bytes --]

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Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Jim Fehlig wrote:
> Shriram Rajagopalan wrote:
>   
>> I was just looking over the patch on blkif.py and I believe there is a bug.
>> --- a/tools/python/xen/util/blkif.py	Fri Dec 10 18:08:19 2010 +0000
>> +++ b/tools/python/xen/util/blkif.py	Wed Jan 05 23:31:24 2011 +0000
>> @@ -71,15 +71,8 @@ def _parse_uname(uname):
>>      if uname.find(":") != -1:
>>          (typ, fn) = uname.split(":", 1)
>>
>> -        if typ == "phy" and not fn.startswith("/"):
>> +        if typ in ("phy", "drbd") and not fn.startswith("/"):
>>              fn = "/dev/%s" %(fn,)
>> -
>> -        if typ == "drbd":
>> -            if not fn.startswith("drbd"):
>> -                (drbdadmstdin, drbdadmstdout) =
>> os.popen2(["/sbin/drbdadm", "sh-dev", fn])
>> -                fn = drbdadmstdout.readline().strip()
>> -            else:
>> -                fn = "/dev/%s" %(fn,)
>>
>>          if typ in ("tap", "tap2"):
>>              (taptype, fn) = fn.split(":", 1
>>
>>
>>  When you specify a drbd disk for a domU, its format is
>>   drbd:<resourceName>
>>   
>>     
>
> Correct.  Sadly, I forgot I was testing on SLES, which contains local
> xend patches to fix problems wrt external block scripts.  One of the
> patches has existed for ages, before many of us were working on xen
> :-).  I would really like to get these changes upstream, even though
> xend is dying.  The first patch is a revert of
> http://xenbits.xensource.com/xen-unstable.hg?rev/152257350930.  The
> second patch, which I've rebased against -unstable, is attached.  Can
> you test it?
>   

Shriram,

Have you had a chance to test my suggestion above (reverting c/s 19444
and using the xend patch we have in SuSE)?  It has been working well for
us, but another "Tested-by:" may convince upstream to take these changes
as well.  Perhaps it is too late for 4.1 as we're at RC2 already.

Thanks!
Jim

Re: [PATCH] xend: drbd improvements

[Shriram Rajagopalan]

darn!.. I missed your earlier email totally, in the flood of emails in
my inbox :(. sorry about
the delayed response.

I dont have pygrub based vm disk images/volumes on my Debian devel boxes.
But I have tested your patches (revert 20158, 19444 & applying your
patch) with pv domUs,
using the "block-drbd" script and the following work fine as expected.
   --Promoting drbd resource to primary before booting VM
   --Automatic secondary->primary resource promotion (at target host)
during live migration

shriram

On Wed, Jan 12, 2011 at 7:38 PM, Jim Fehlig <jfehlig@novell.com> wrote:
> Jim Fehlig wrote:
>> Shriram Rajagopalan wrote:
>>
>>> I was just looking over the patch on blkif.py and I believe there is a bug.
>>> --- a/tools/python/xen/util/blkif.py Fri Dec 10 18:08:19 2010 +0000
>>> +++ b/tools/python/xen/util/blkif.py Wed Jan 05 23:31:24 2011 +0000
>>> @@ -71,15 +71,8 @@ def _parse_uname(uname):
>>>      if uname.find(":") != -1:
>>>          (typ, fn) = uname.split(":", 1)
>>>
>>> -        if typ == "phy" and not fn.startswith("/"):
>>> +        if typ in ("phy", "drbd") and not fn.startswith("/"):
>>>              fn = "/dev/%s" %(fn,)
>>> -
>>> -        if typ == "drbd":
>>> -            if not fn.startswith("drbd"):
>>> -                (drbdadmstdin, drbdadmstdout) =
>>> os.popen2(["/sbin/drbdadm", "sh-dev", fn])
>>> -                fn = drbdadmstdout.readline().strip()
>>> -            else:
>>> -                fn = "/dev/%s" %(fn,)
>>>
>>>          if typ in ("tap", "tap2"):
>>>              (taptype, fn) = fn.split(":", 1
>>>
>>>
>>>  When you specify a drbd disk for a domU, its format is
>>>   drbd:<resourceName>
>>>
>>>
>>
>> Correct.  Sadly, I forgot I was testing on SLES, which contains local
>> xend patches to fix problems wrt external block scripts.  One of the
>> patches has existed for ages, before many of us were working on xen
>> :-).  I would really like to get these changes upstream, even though
>> xend is dying.  The first patch is a revert of
>> http://xenbits.xensource.com/xen-unstable.hg?rev/152257350930.  The
>> second patch, which I've rebased against -unstable, is attached.  Can
>> you test it?
>>
>
> Shriram,
>
> Have you had a chance to test my suggestion above (reverting c/s 19444
> and using the xend patch we have in SuSE)?  It has been working well for
> us, but another "Tested-by:" may convince upstream to take these changes
> as well.  Perhaps it is too late for 4.1 as we're at RC2 already.
>
> Thanks!
> Jim
>
>



-- 
perception is but an offspring of its own self

Re: [PATCH] xend: drbd improvements

[Ian Jackson]

Jim Fehlig writes ("Re: [Xen-devel] [PATCH] xend: drbd improvements"):
> Have you had a chance to test my suggestion above (reverting c/s 19444
> and using the xend patch we have in SuSE)?  It has been working well for
> us, but another "Tested-by:" may convince upstream to take these changes
> as well.  Perhaps it is too late for 4.1 as we're at RC2 already.

I'd love to have another test report.  I didn't apply these patches
because it wasn't clear to me exactly what the proposed changes were
and, as you say, that they had been sufficiently tested.

I think this change will be fine for 4.1, especially if the patch
doesn't change non-drbd codepaths.

Ian.

Re: [PATCH] xend: drbd improvements

[Jim Fehlig]

Ian Jackson wrote:
> Jim Fehlig writes ("Re: [Xen-devel] [PATCH] xend: drbd improvements"):
>   
>> Have you had a chance to test my suggestion above (reverting c/s 19444
>> and using the xend patch we have in SuSE)?  It has been working well for
>> us, but another "Tested-by:" may convince upstream to take these changes
>> as well.  Perhaps it is too late for 4.1 as we're at RC2 already.
>>     
>
> I'd love to have another test report.

Shriram reported that he successfully tested these changes.

>   I didn't apply these patches
> because it wasn't clear to me exactly what the proposed changes were
> and, as you say, that they had been sufficiently tested.
>   

The revert of c/s 19444 simply removes more 'drbd' cruft from xend
internals.

As for my xend patch, is the commit message that vague?

-------------------------
xend: improve psudeo-bootloader support for external block scripts

Userspace tools support external block scripts (e.g. block-drbd
provided by drbd project). The psuedo-bootloader setup code in
xend has a few limitations wrt external block scripts, which this
patch addresses.

blkif.py: parse_uname() utility function should be able to parse a
disk specifier understood by the rest of the tools.

XendDomainInfo.py: Block devices using external block scripts must
be attached to dom0 before running the psuedo-bootloader.
-------------------------

I can improve it if need be.

Regards,
Jim

Re: [PATCH] xend: drbd improvements

[Ian Jackson]

Jim Fehlig writes ("Re: [Xen-devel] [PATCH] xend: drbd improvements"):
> Correct.  Sadly, I forgot I was testing on SLES, which contains local
> xend patches to fix problems wrt external block scripts.  One of the
> patches has existed for ages, before many of us were working on xen
> :-).  I would really like to get these changes upstream, even though
> xend is dying.  The first patch is a revert of
> http://xenbits.xensource.com/xen-unstable.hg?rev/152257350930.  The
> second patch, which I've rebased against -unstable, is attached.  Can
> you test it?

Thanks, Jim, for this patch, which I have now applied along with the
revert of 19444:152257350930.

Ian.