Ldapsearch: 2 types of input. Why does only one work?

Question

LDAP

Good afternoon,
there are two ways to connect to LDAP:

1. [email protected]:/# ldapsearch -h localhost -V -D "UID=username,OU=System Users,DC=domain,DC=local" -w pass
   
2. [email protected]:/# ldapsearch -h localhost -V -D "domain\username" -w pass
   

attention question!
why is there an error in the first case:
ldap_bind: Invalid credentials (49)
additional info: Simple Bind Failed: NT_STATUS_LOGON_FAILURE
?

Answer 1

earned and the second option.
the upgrade from 4.1 to 4.2 did not pass without a trace.