[Libguestfs] libguestfs-tools with libvirt SASL authentication

Hello, I'm running into an issue using the 'virt-df' command when SASL is enabled in libvirt. I'm running version 1.26.5 of libguestfs on an Ubuntu 14.04 OS. I'm running 'virt-df' for all guests at one time, not specifying a domain or image to use. I was expecting a SASL authentication prompt but to no avail. Below is a sample run: root@all-in-one:~# virt-df -P 15 libvirt: XML-RPC error : authentication failed: Failed to start SASL negotiation: -4 (SASL(-4): no mechanism available: No worthy mechs found) virt-df: could not connect to libvirt (code 45, domain 7): authentication failed: Failed to start SASL negotiation: -4 (SASL(-4): no mechanism available: No worthy mechs found) However, if I do specify a domain to run on, I am prompted for SASL authentication: root@all-in-one:~# virt-df -d instance-0000004d libvirt needs authentication to connect to libvirt URI NULL (see also: http://libvirt.org/auth.html http://libvirt.org/uri.html) Please enter your authentication name: nova@all-in-one Please enter your password: Filesystem 1K-blocks Used Available Use% instance-0000004d:/dev/sdb 458 458 0 100% instance-0000004d:/dev/sda1 22773 12223 9322 54% Is there any way to successfully run 'virt-df' for all instances at once while SASL is enabled in libvirt? Thanks, Dan Ryder