[Bug 1861693] [NEW] Default URI changed to qemu:///session?

[Andreas Hasenack]

Public bug reported:

focal (upgraded from eoan)
libvirt 6.0.0-0ubuntu1

It seems that the default qemu libvirt changed from qemu:///system to
qemu:///session, or something else is going on.

I was debugging multipass's libvirt backend, and this started happening with focal:
"""
andreas at nsnx:~$ sudo multipass set local.driver=libvirt
[sudo] password for andreas: 
andreas at nsnx:~$ virsh list --all
 Id   Name   State
--------------------

andreas at nsnx:~$ multipass delete -p bionic-nvdimm

andreas at nsnx:~$ multipass launch -c 2 -m 2G -n bionic-nvdimm --cloud-init ~/cloud-init-proxy daily:bionic
Starting bionic-nvdimm |-i\|/-l\|t-\|/-\                                        
Launched: bionic-nvdimm                                                         

andreas at nsnx:~$ virsh list --all                                                
 Id   Name   State
--------------------

andreas at nsnx:~$
"""

I expected to see my VMs (all my existing ones plus the new one) listed by virsh. Further debugging showed that virsh, without an explicit -c option, was connecting to qemu:///session:
$ LIBVIRT_DEBUG=1 virsh list 2>&1 | grep Auto-probed
2020-02-03 15:28:49.982+0000: 710151: debug : doRemoteOpen:1356 : Auto-probed URI is qemu:///session

Which indeed returns an empty list.

If I specify -c qemu:///system, then I see my VMs again, including the one just launched by multipass:
$ virsh -c qemu:///system list --all
 Id   Name               State
-----------------------------------
 3    bionic-nvdimm      running
 -    focal-containerd   shut off
 -    trusty-amd64-ua    shut off
 -    trusty-desktop     shut off
 -    trusty-i386-ua     shut off
 -    trusty-ua          shut off

I asked a colleague who is on eoan to check, and the default there seems to be qemu:///system:
2020-02-03 15:30:13.229+0000: 7277: debug : virConnectGetDefaultURI:786 : Using LIBVIRT_DEFAULT_URI 'qemu:///system'
2020-02-03 15:30:13.229+0000: 7277: debug : virConnectOpenInternal:918 : Split "qemu:///system" to URI components:
  scheme qemu
2020-02-03 15:30:13.229+0000: 7277: debug : virConnectOpenInternal:1012 : Matching any URI scheme for 'qemu'
2020-02-03 15:30:13.229+0000: 7277: debug : doRemoteOpen:948 : proceeding with name = qemu:///system
2020-02-03 15:30:13.231+0000: 7277: debug : doRemoteOpen:1210 : Trying to open URI qemu:///system

** Affects: libvirt (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: champagne

** Tags removed: champaigne
** Tags added: champagne

-- 
You received this bug notification because you are a member of Ubuntu
Server, which is subscribed to libvirt in Ubuntu.
https://bugs.launchpad.net/bugs/1861693

Title:
  Default URI changed to qemu:///session?

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1861693/+subscriptions