[Libguestfs] [PATCH] convert_linux: translate the first CD-ROM's references in boot conf files

[Richard W.M. Jones]

On Wed, Dec 15, 2021 at 03:33:00PM +0000, Richard W.M. Jones wrote:
> On Wed, Dec 15, 2021 at 04:14:42PM +0100, Laszlo Ersek wrote:
> > Before posting v2, I intended to test it :) , so I installed a new RHEL5 guest, and tried to run virt-v2v (with the v2 patch) on it:
> > 
> > virt-v2v -i libvirt -o local -os ~/output rhel5.11
> 
> As a general comment, you might want to check virt-v2v 1.44 branch to
> see if these problems are regressions in virt-v2v or something else.
> 
> In this case ...
> 
> > Unfortunately, things break before my code gets a chance to run; here:
> > 
> >   (* Fail early if i_apps is empty.  Certain steps such as kernel
> >    * detection won't work without this.  If the list is empty it
> >    * likely indicates that libguestfs inspection is broken for
> >    * this guest.  See for example RHBZ#1965147.
> >    *)
> >   if inspect.i_apps = [] then
> >     error (f_"inspection of the package database failed for ...
> > 
> > This seems to come from an empty apps list, from "convert/inspect_source.ml", which in turn invokes "g#inspect_list_applications2".
> > 
> > I turned to guestfish, and ran the following manually:
> > 
> > inspect-os
> > inspect-get-mountpoints /dev/VolGroup00/LogVol00
> > inspect-list-applications2 /dev/VolGroup00/LogVol00
> > 
> > Indeed the last command does not return anything. I turned on "verbose" and "trace" then, and then I see a failure in the daemon:
> > 
> > libguestfs: trace: inspect_list_applications2 "/dev/VolGroup00/LogVol00"
> > libguestfs: trace: inspect_get_type "/dev/VolGroup00/LogVol00"
> > libguestfs: trace: inspect_get_type = "linux"
> > libguestfs: trace: inspect_get_package_format "/dev/VolGroup00/LogVol00"
> > libguestfs: trace: inspect_get_package_format = "rpm"
> > libguestfs: trace: internal_list_rpm_applications
> > \x1b[31;1merror: \x1b[0m\x1b[1mUnable to open /usr/lib/rpm/rpmrc for reading: No such file or directory.
> > \x1b[0m\x1b[31;1merror: \x1b[0m\x1b[1mno dbpath has been set
> > \x1b[0m\x1b[31;1merror: \x1b[0m\x1b[1mcannot open Packages database in 
> > \x1b[0mlibrpm returned 0 installed packages
> > libguestfs: trace: internal_list_rpm_applications = <struct guestfs_application2_list(0)>
> > libguestfs: trace: inspect_list_applications2 = <struct guestfs_application2_list(0)>
> 
> ... I think this is potentially an instance of:
> 
>   [sorry, BZ is down  - I will follow up with the bug number]

https://bugzilla.redhat.com/show_bug.cgi?id=1965147

> The new thing here (not really related to virt-v2v) is that RPM itself
> changed from Berkley DB to sqlite.  However old libguestfs actually
> accessed the BDB directly and could not read the RPM databases of new
> guests.  So we switched to using librpm (instead of direct access),
> but this meant for a time we couldn't access the RPM DBs of *old*
> guests.  However that was eventually fixed in RPM.
> 
> https://github.com/libguestfs/libguestfs/commit/c9ee831affed55abe0f928134cbbd2ed83b2f510
> 
> Rich.
> 
> > The file "/usr/lib/rpm/rpmrc" absolutely exists in the guest (I booted it up separately, and checked it).
> > 
> > It seems that "internal_list_rpm_applications" [daemon/rpm.ml] calls chroot, and uses a child project -- can that be related to the issue?
> > 
> > Anyway, I think I'll post v2, just saying that I could not actually test it.
> > 
> > Thanks,
> > Laszlo
> 
> -- 
> 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

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top