I have a database archive mode, but is crash, i connot recover because dont have the archive files.
I put this parameters in init.ora

_allow_resetlogs_corruption=true
_corrupted_rollback_segments=(r01,r02,r03,r04)

and i intente startup the database with

alter database mount
recover database until cancel using backup controlfile
alter database open resetlogs

but i get this message error

alter database open x
ORA-00704: bootstrap process failure x
ORA-00604: error occurred at recursive SQL level 1 x
ORA-00955: name is already used by an existing object
ORA-01555 shaphot too old (rollback segment too small)

what do i to do ...

I need recover the database consistent o inconsistent