sudoers is a file (typically located at
/etc/sudoers) containing a list of which users may execute what and various other rules.
sudoers file is composed of two types of entries: aliases (basically variables) and user specifications (which specify who may run what).
When multiple entries match for a user, they are applied in order. Where there are conflicting values, the last match is used (which is not necessarily the most specific match).
Since the sudoers file is parsed in a single pass, order is important. In general, you should structure sudoers such that the
Cmnd_Alias specifications come first, followed by any
Default_Entry lines, and finally the
Runas_Alias and user specifications. The basic rule of thumb is you cannot reference an Alias that has not already been defined.
Below are example sudoers entries:
User_Alias FULLTIMERS = millert, mikef, dowdy User_Alias PARTTIMERS = bostley, jwfox, crawl User_Alias WEBMASTERS = will, wendy, wim Runas_Alias OP = root, operator Runas_Alias DB = oracle, sybase Host_Alias SPARC = bigtime, eclipse, moet, anchor :\ SGI = grolsch, dandelion, black :\ ALPHA = widget, thalamus, foobar :\ HPPA = boa, nag, python Host_Alias CUNETS = 126.96.36.199/255.255.0.0 Host_Alias CSNETS = 188.8.131.52, 184.108.40.206/24, 220.127.116.11 Host_Alias SERVERS = master, mail, www, ns Host_Alias CDROM = orion, perseus, hercules Cmnd_Alias DUMPS = /usr/bin/mt, /usr/sbin/dump, /usr/sbin/rdump,\ /usr/sbin/restore, /usr/sbin/rrestore Cmnd_Alias KILL = /usr/bin/kill Cmnd_Alias PRINTING = /usr/sbin/lpc, /usr/bin/lprm Cmnd_Alias SHUTDOWN = /usr/sbin/shutdown Cmnd_Alias HALT = /usr/sbin/halt Cmnd_Alias REBOOT = /usr/sbin/reboot Cmnd_Alias SHELLS = /usr/bin/sh, /usr/bin/csh, /usr/bin/ksh, \ /usr/local/bin/tcsh, /usr/bin/rsh, \ /usr/local/bin/zsh Cmnd_Alias SU = /usr/bin/su
Create your own custom prompt:
$ echo 'Defaults passprompt="MY LAUNCH CODE: "' > /etc/sudoers.d/custom_prompt