@nikolam -> What PI was your flash booting?

Rescue mode != single-user-mode , but maybe that should be a bit more clear?!

I understand. Newest made USB flash.

Ah I think I was in the hurry and have seen only rescue mode available in options.

And if i just boot from USB flash, I would get system that has zones pool, just booting in that PI version . And I wanted to change root password. It also passed a lot of time since I had a chance to use SmartOS release default password.

I never since now heard of using root/root I think that before I only remember before, I always needed to enter default root password.