Connect to VM fails with the error : "error: Failed to connect socket to '@/sysadmin/.libvirt/libvirt-sock': Connection refused"

Issue

Trying to connect to console of the KVM virtual machine.

It´s failing with the error message below :

"error: Failed to connect socket to '@/sysadmin/.libvirt/libvirt-sock': Connection refused"

Some outputs from the server :

sudo virsh list --all

[sudo] password for userxx:
 Id Name                 State
----------------------------------
 18 vm1             running
 20 vm2             running


virsh console vm1

error: Failed to reconnect to the hypervisor
error: no valid connection
error: Failed to connect socket to '@/sysadmin/.libvirt/libvirt-sock': Connection refused

Following errors are also seen in /var/log/libvirt/libvirtd.log

 error : daemonStreamHandleAbort:590 : stream aborted at client request
 error : virFileOpenAsNoFork:668 : failed to create file '/mnt/dumpfile': Permission denied
 error : virFileOpenAsNoFork:668 : failed to create file '/mnt/dumpfile': Permission denied
 error : qemuOpenFile:2332 : Error from child process creating '/mnt/dumpfile': Permission denied
 error : virFileOpenAsNoFork:687 : cannot chown '/mnt/dumpfile' to (0, 0): Operation not permitted
 error : virFileOpenAsNoFork:687 : cannot chown '/mnt/dumpfile' to (107, 107): Operation not permitted
 error : qemuOpenFile:2332 : Error from child process creating '/mnt/dumpfile': Operation not permitted