Samantha -

From the logs, it looks like the autopart requests are doing something wrong here, but I wasn't able to reproduce.

This is not reproducible with Anaconda from 7.3. But on 7.4, despite the installclass, Anaconda is attempting to create:

/boot
PV
-swap
thinpv
-everything else

There are 2 problems:

*swap should be on the the thin pv
*the 'normal' PV is taking the entire disk, which does not leave space.

We haven't seen this before, and don't have a reproducer (Laurent does), but it's pretty apparent from the logs.

Any ideas here?

Please attach the program.log from the installation.

Fortunately program.log is dumped in the anaconda-tb-* file. This looks relevant:
16:58:31,729 INFO program: Running... lvm lvcreate --thinpool rhvh_hosted-engine1/pool00 --size 79224m --poolmetadatasize 40 --chunksize 64 --config  devices { preferred_names=["^/dev/mapper/", "^/dev/md/", "^/dev/sd"] filter=["r|/sda$|","r|/sdb$|","r|/sdc$|"] } 
16:58:31,756 INFO program:   /usr/sbin/modprobe failed: 1
16:58:31,756 INFO program:   thin-pool: Required device-mapper target(s) not detected in your kernel.
16:58:31,756 INFO program:   Run `lvcreate --help' for more information.
16:58:31,756 DEBUG program: Return code: 3

The traceback itself looks like it may be an issue with our storage library, so I'm flipping components.

Looks to me like Samantha nailed it. Something went wrong with the compose, causing the required kernel modules to not be available (or loaded).

Any update on this?
Chance that a fix can get into RHEL 7.6?

I don't believe there is a problem in blivet. It looks like the runtime images do not contain the dm-thin kernel module. I don't know how the installation media is created, but I would take a look at that process to find the problem.

See previous comment. I don't know what your process is for creating the installer runtime images, but it seems to be the problem.

Please reassign to an appropriate component as I don't have the knowledge of the RHV/ovirt stack to do so correctly.

You mentioned the 7.3 kickstart - is this a PXE installation, if so, please make sure you're using the correct kernel+initrd combination.  The modprobe error usually happens on wrong PXE configurations, if the kernel version and the version of the modules in the initrd do not match

Hi
Looks like this affect also the 4.2 image, we have the same error about device-mapper not detected for one of our customer.
Ryan Have you seen it also for 4.2 by chance ? 
Thanks !

I haven't, but I moved to a different RHV team in September.

Which 4.2 version? The underlying version of RHEL is important

Hi Ryan 
Sorry for the ping then, it's redhat-virtualization-host-4.2-20181026 so 7.6 
Thx

Jaroslav, is your pxe environment set correctly with the kernel+initrd that match this version of rhvh ?

Hi Yuval 
You were right, cu fixed the PXE config and installation was successful .
Thanks for hint !

Thanks for the update ! Closing this according to Comment 15