How do I recover the password for SYS?
You don’t. You log into the database server as the administrative user who has the dba group priviledge and assuming your on at least the 10g version
sqlplus / as sysdba
alter user sys identified by new_passwork;
where new_password is the password you want to use for the SYS user. Thats it. You can now login as the sys user using the new password. In version 11 and higher the password is case sensitive so remember the new password.