OpenNebula

Hello I have two different installations of OpenNebula 5.2 with sunstone, and both have uploading images is not work via web insterface:

I got theese error messages in sunstone:

- Cannot contact server: is it running and reachable?
- It appears there was a server exception. Please check server's log.

I checked sunstone.log log, and see only this in each case:

"POST /upload_chunk HTTP/1.1" 200 - 0.0281
    "POST /upload_chunk HTTP/1.1" 200 - 0.1321
    "POST /upload_chunk HTTP/1.1" 200 - 0.0155
    "POST /upload_chunk HTTP/1.1" 200 - 0.0205
    "POST /upload_chunk HTTP/1.1" 200 - 0.0130
    "POST /upload_chunk HTTP/1.1" 200 - 0.0158
    "POST /upload HTTP/1.1" 500 - 30.0446

I checked oned.log logs, they are have no any messages about uploding image.

Also I checked temprary location: /var/tmp/ - it is exist, have right permissions and have available needed free size.

I watch about it:

When I start upload, my image appears here and start growing.
After it uploloaded by 100%, progress bar in sunstone freezed, and next inscription appears: Registering in OpenNebula.
After some time ~1 minute, I get the above errors.

I do not know where to dig further, I tried even strace, but it has not shown anything interesting.
I feel that there is no some action for finish registering image successful. That's just what, any ideas?