The sulog file lists every use of the su command, not only the su attempts that are used to switch from user to superuser.
# more /var/adm/sulog SU 12/20 16:26 + pts/0 stacey-root SU 12/21 10:59 + pts/0 stacey-root SU 01/12 11:11 + pts/0 root-rimmer SU 01/12 14:56 + pts/0 pmorph-root SU 01/12 14:57 + pts/0 pmorph-root
The entries display the following information:
The date and time that the command was entered.
The port from which the command was issued.
The name of the user and the name of the switched identity.
The su logging in this file is enabled by default through the following entry in the /etc/default/su file:
Entries that include ??? indicate that the controlling terminal for the su command cannot be identified. Typically, system invocations of the su command before the desktop appears include ???, as in SU 10/10 08:08 + ??? root-root. After the user starts a desktop session, the ttynam command returns the value of the controlling terminal to the sulog: SU 10/10 10:10 + pts/3 jdoe-root.
Entries similar to the following can indicate that the su command was not invoked on the command line: SU 10/10 10:20 + ??? root-oracle. The user might have switched to the oracle role by using a GUI.