18.04 supermicro cloud servers boot loop

I have strange situation, maas won’t boot my servers with 18.04 ubuntu, but if I repack initrd from gzip to lzma - it starts working. I had to change boot-resource “current” symlink to directory and make it immutable with chattr for a moment, just so boot-resource import/update won’t overwrite my repacked initrd. But I’m baffled with this behavior. Any ideas?

Also I found similar problem [solved] Boot loop with 18.04 here, but I didn’t do anything with interfaces so that’s not really my case. I asked same question on askubuntu, so far only one user reported same problem (which in his case somewhat solved by using another kernel, which didn’t work for me at all)

I should add that my solution is far from ideal cause maas trying to update images and in the end I’m getting zero disk space problem with my “solution” so I really want to find how to fix this.