Marco Pizzoli writes:
Can anyone explain to me what this kind of attribute is this?
*conn=0 op=3 SRCH attr=1.1
It's the LDAP way to suppress the default that a search returns all user attributes, as if you asked for attribute "*". If you ask only for attribute 1.1, the search returns only DNs and no attributes.
Actually it's just an object identifier chosen arbitrarily by the LDAP standard as one which "does not and cannot correspond to any attribute in use" (RFC 4511). Any other nonexistent attribute would have served as well.