On Thu, Jul 13, 2023 at 07:10:45PM +0200, Laszlo Ersek wrote: > Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2184967 > > This series makes both backends prefer passt over slirp for appliance > networking, if QEMU or libvirt (respectively) is recent enough, and > passt is installed. > > My test setup is: > > $ virt-builder fedora-38 > > Then, each test run looks like this: > > Terminal#1: > > $ ./run rescue/virt-rescue --network --ro -a fedora-38.img > > Terminal#2: > > - check if "passt" is running (ps -ef, pgrep, ...), provided it *should* > be running > > Terminal#1: > > ><rescue> ping -c 3 8.8.8.8 > ><rescue> ip neighbor > ><rescue> ip addr > ><rescue> ip route > > Expected results (in the above order), always on the "eth0" lines: > - all three pings succeed (get replies) > - 52:56:00:00:00:02 > - 169.254.2.15/16 > - default via 169.254.2.2
Another good test (and the one that really matters) would be something like this on Terminal #1 ... ><rescue> chroot /sysroot bash ><rescue> dnf install emacs (or some other package). If dnf can see the Fedora repositories despite the network setup being slightly wonky, that will mean that virt-customize should work. > Actual results: > > (1) At current master (13c7052ff96d): > > (1.1) With "LIBGUESTFS_BACKEND=direct": > > Pass, this is the baseline. > > (1.2) With "LIBGUESTFS_BACKEND=libvirt": > > Pass, this is the baseline. > > (2) With this series applied: > > (2.1) With passt not installed: > > (2.1.1) With "LIBGUESTFS_BACKEND=direct": > > Pass, this is a regression test concerning the absence of > "passt". > > (2.1.2) With "LIBGUESTFS_BACKEND=libvirt": > > Pass, this is a regression test concerning the absence of > "passt". > > (2.2) With passt installed: > > (2.2.1) With "LIBGUESTFS_BACKEND=direct": > > Pass, this verifies the new feature. > > (2.2.2) With "LIBGUESTFS_BACKEND=libvirt": > > Basic connectivity works fine (i.e., the pings). > > The "ip neighbor" and "ip route" checks fail. In addition, the > "ip addr" check *partially* fails. All that is due to libvirt > bugs: > > (a) Libvirt specifies the *guest MAC* (virtio-net MAC) as the > *host MAC* for passt, with a wrong "--mac-addr" option (from > libvirt commit a56f0168d576, "qemu: hook up passt config to > qemu domains", 2023-01-10). This breaks "ip neighbor". > > (b) Libvirt doesn't pass the "--gateway" option to passt. This > breaks "ip route". Namely, passt (following its default > behavior) sets the guest's gateway to 192.168.0.1, which is > the gateway for my *host*. > > (c) "ip addr" also reports "169.254.2.15/1". The IP address is > fine, but the netmask is wrong; it's not /16. This is most > likely a consequence of (b) -- normally the gateway is > supposed to be on the same Ethernet segment (subnet) as the > endpoint! 192 decimal is 11000000 binary, while 169 decimal > is 10101001 binary, and their longest common initial bit > sequence is just 1 bit -- hence the /1, most likely. > > I've filed <https://bugzilla.redhat.com/show_bug.cgi?id=2222766> > about these. It's good that this work has found a bunch of libvirt bugs! Rich. > The upshot is that "appliance networking with passt" works with either > backend, but with the libvirt backend, there are some appliance-visible > differences from the SLIRP environment. Whether that's a problem in > practice, I can't tell (probably not a problem) -- dependent on future > decisions about RHBZ#2222766, we might want to update the libvirt > backend code introduced here. > > Laszlo > > Laszlo Ersek (7): > lib: fix NETWORK_ADDRESS: make it an actual IP address, not a subnet > base > lib/launch-libvirt: support networking with passt > docs: fix broken link in the guestfs manual > docs: clarify sockdir's separation > lib: move guestfs_int_create_socketname() from "launch.c" to > "tmpdirs.c" > lib: introduce guestfs_int_make_pid_path() > lib/launch-direct: support networking with passt > > fish/guestfish.pod | 4 +- > generator/actions_properties.ml | 8 +- > lib/guestfs-internal.h | 32 ++++- > lib/guestfs.pod | 6 +- > lib/launch-direct.c | 147 +++++++++++++++++++- > lib/launch-libvirt.c | 11 ++ > lib/launch.c | 54 +++---- > lib/tmpdirs.c | 41 ++++++ > 8 files changed, 263 insertions(+), 40 deletions(-) > > > base-commit: 13c7052ff96d5ee99ec1b1252f1a3b4d7aed44d2 > _______________________________________________ > Libguestfs mailing list > Libguestfs@redhat.com > https://listman.redhat.com/mailman/listinfo/libguestfs -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 100 libraries supported. http://fedoraproject.org/wiki/MinGW _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
