Bug 1297690

Summary:	XML-RPC error : Cannot write data: Transport endpoint is not connected
Product:	Red Hat Enterprise Linux 7	Reporter:	Richard W.M. Jones <rjones>
Component:	libvirt	Assignee:	Martin Kletzander <mkletzan>
Status:	CLOSED ERRATA	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	7.3	CC:	agedosier, alexey.kosilin, berrange, cfergeau, clalancette, crobinso, dyuan, extras-qa, fdeutsch, itamar, jforbes, jfrieben, jsuchane, laine, libvirt-maint, mcatanzaro+wrong-account-do-not-cc, mclasen, mzhan, rbalakri, rjones, sankarshan, veillard, virt-maint, yafu
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	libvirt-1.3.1-1.el7	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	1271183	Environment:
Last Closed:	2016-11-03 18:35:52 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1271183
Bug Blocks:	910269

Description Richard W.M. Jones 2016-01-12 08:58:05 UTC

+++ This bug was initially created as a clone of Bug #1271183 +++

Cloning to ensure this bug is fixed in RHEL 7.  (It affects 7.2 for
sure, possibly earlier).

Description of problem:

libvirt still fails with qemu:///session intermittently:
libguestfs: opening libvirt handle: URI = qemu:///session, auth = default+wrapper, flags = 0
libvirt: XML-RPC error : Cannot write data: Transport endpoint is not connected
libguestfs: error: could not connect to libvirt (URI = qemu:///session): Cannot write data: Transport endpoint is not connected [code=38 domain=7]
libguestfs-test-tool: failed to launch appliance

There's another bug about this, but I can't find it right now.

Version-Release number of selected component (if applicable):

libvirt-1.2.20-1.fc24.x86_64

How reproducible:

Unknown, but not often.  Seems to happen when user libvirtd
starts up the first time, but not every time.

Steps to Reproduce:
1. Run: libguestfs-test-tool as non-root.

--- Additional comment from Fabian Deutsch on 2016-01-07 06:25:12 EST ---

We are also seeing this issue on CentOS 7

--- Additional comment from Cole Robinson on 2016-01-11 20:24:06 EST ---

I'm pretty sure these patches fix things:

https://www.redhat.com/archives/libvir-list/2016-January/msg00422.html

--- Additional comment from Michael Catanzaro on 2016-01-11 23:07:56 EST ---

Thanks a bunch Cole; I rely on libvirt (via Boxes) and it's annoying when it doesn't start up properly. If you do a Fedora build, I'd be happy to test it!

Comment 2 Jaroslav Suchanek 2016-01-21 11:57:52 UTC

Fixed by

commit 2eb7a975756d05a5b54ab4acf60083beb6161ac6
Author: Cole Robinson <crobinso>
Date:   Mon Jan 11 20:13:38 2016 -0500

    rpc: socket: Don't repeatedly attempt to launch daemon
    
    On every socket connect(2) attempt we were re-launching session
    libvirtd, up to 100 times in 5 seconds.
    
    This understandably caused some weird load races and intermittent
    qemu:///session startup failures
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1271183

Comment 4 Zeeshan Ali 2016-04-27 12:13:13 UTC

Thanks Cole for fixing this!

Comment 7 yafu 2016-09-09 06:40:52 UTC

Reproduce with libvirt-1.2.17-13.el7_2.5.x86_64.

Test steps:
1.Reinstall libvirt:
 #yum -y reinstall libvirt*

2.Clean caches:
 #echo 3 > /proc/sys/vm/drop_caches

3.Run libguestfs-test-tool with non-root:
 $libguestfs-test-tool
  ...
  libguestfs: opening libvirt handle: URI = qemu:///session, auth = default+wrapper, flags = 0
libvirt: XML-RPC error : Cannot write data: Transport endpoint is not connected
libguestfs: error: could not connect to libvirt (URI = qemu:///session): Cannot write data: Transport endpoint is not connected [code=38 domain=7]
libguestfs-test-tool: failed to launch appliance
 ...

Verify pass with libvirt-2.0.0-8.el7.x86_64.

Test steps:
1.Using libguestfs
a).Reinstall libvirt:
 #yum -y reinstall libvirt*

b).Clean caches:
 #echo 3 > /proc/sys/vm/drop_caches

c).Run libguestfs-test-tool with non-root:
  $libguestfs-test-tool
   no error output.

Comment 8 yafu 2016-09-09 06:54:05 UTC

Hi,Richard,

Would you help to check the steps in comment 7 are enough for verifying this bug?
Thanks a lot.

Comment 9 yafu 2016-09-14 09:04:56 UTC

Reproduce the bug using libvirt-python.
Test version:
libvirt-python-1.2.17-2.el7.x86_64
libvirt-1.2.17-13.el7_2.5.x86_64
  
Test steps:
1.Reinstall libvirt:
 #yum -y reinstall libvirt*

2.Clean caches:
 #echo 3 > /proc/sys/vm/drop_caches

3.Run the scripts with non-root:
  https://bugzilla.redhat.com/show_bug.cgi?id=1240283#c9
  $ python bug1240283.py 
libvirt: XML-RPC error : Cannot write data: Transport endpoint is not connected
Traceback (most recent call last):
  File "bug1240283.py", line 14, in <module>
    conn = libvirt.openReadOnly(None)
  File "/usr/lib64/python2.7/site-packages/libvirt.py", line 268, in openReadOnly
    if ret is None:raise libvirtError('virConnectOpenReadOnly() failed')
libvirt.libvirtError: Cannot write data: Transport endpoint is not connected


Verify pass using libvirt-python.
Test version:
libvirt-python-2.0.0-2.el7.x86_64
libvirt-2.0.0-8.el7.x86_64

Test steps:
1.Reinstall libvirt:
 #yum -y reinstall libvirt*

2.Clean caches:
 #echo 3 > /proc/sys/vm/drop_caches

3.Run the scripts with non-root:
  https://bugzilla.redhat.com/show_bug.cgi?id=1240283#c9
  $ python bug1240283.py 
  NOT reproduced RHBZ#1240283

Comment 11 errata-xmlrpc 2016-11-03 18:35:52 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2016-2577.html