It should be!
The proxy code just acts like either a V4 client (ProxyV4 in the current tree) or V3 client (ProxyV3). Ganesha itself handles the clients and whatever they want to speak (v3, v4, 9p even I think, etc.).
That's what I thought, so that's good news.
Your use of Name = proxy, implies you're on an older branch perhaps, and I feel like I've had some bugfixes in the Proxy V4 code (in particular, I know for my ProxyV3 I had to fixup the handling of path vs pseudo... I don't recall if ProxyV4 had the same problem or not). I don't have any experience with the handle mapping code (though I've certainly looked at it). Is it strictly required for your test?
Regarding the "Name = proxy" configuration, do you have examples of what I should use for the Proxy V4 code? I had a hard time finding concrete examples for the Proxy code in particular.
I'm running Ganesha 3.5 on CentOS 8, out of the SCL Ganesha repo. I've installed the nfs-ganesha and nfs-ganesha-proxy packages (along with vfs and utils). If there's a different version that I should be using, please let me know - I'm not opposed to building from source, either.
Regarding the handle mapping, I have tried it both enabled and disabled and the experience is identical. It's enabled in the config that I sent over because that's the last thing I tried. I can disabled it, again, just to make sure it isn't adding any rabbit holes to the debugging process.
Either way, please provide some debug logs. You may want to add debug logging to NFS_PROTO or whatever the name is as well. (And if I finally get around to fixing my IRC setup, you can find folks in #ganesha, too for more live debugging).
Yeah, no problem - here are the logs in a Pastbin:
I tried adding "NFS_PROTO = FULL_DEBUG;" to the components section of the configuration, but I'm not sure I got that correct. I'll go back and look at the available components and try a few other things - maybe NFS_V4 or something like that?