MIT Kerberos Documentation

Supported date and time formats

Time duration

This format is used to express a time duration in the Kerberos configuration files and user commands. The allowed formats are:

Format Example Value
h:m[:s] 36:00 36 hours
NdNhNmNs 8h30s 8 hours 30 seconds
N (number of seconds) 3600 1 hour

Here N denotes a number, d - days, h - hours, m - minutes, s - seconds.


The time interval should not exceed 2147483647 seconds.


Request a ticket valid for one hour, five hours, 30 minutes
and 10 days respectively:

  kinit -l 3600
  kinit -l 5:00
  kinit -l 30m
  kinit -l "10d 0h 0m 0s"

getdate time

Some of the kadmin and kdb5_util commands take a date-time in a human-readable format. Some of the acceptable date-time strings are:

  Format Example
Date mm/dd/yy 07/27/12
month dd, yyyy Jul 27, 2012
yyyy-mm-dd 2012-07-27
Absolute time HH:mm[:ss]pp 08:30 PM
hh:mm[:ss] 20:30
Relative time N tt 30 sec
Time zone Z EST
z -0400

(See Abbreviations used in this document.)


Create a principal that expires on the date indicated:
    addprinc test1 -expire "3/27/12 10:00:07 EST"
    addprinc test2 -expire "January 23, 2015 10:05pm"
    addprinc test3 -expire "22:00 GMT"
Add a principal that will expire in 30 minutes:
    addprinc test4 -expire "30 minutes"

Absolute time

This rarely used date-time format can be noted in one of the following ways:

Format Example Value
yyyymmddhhmmss 20141231235900 One minute before 2015 2014.
yymmddhhmmss 141231235900
dd-month-yyyy:hh:mm:ss 31-Dec-2014:23:59:00
hh:mm:ss 20:00:00 8 o’clock in the evening
hhmmss 200000

(See Abbreviations used in this document.)


Set the default expiration date to July 27, 2012 at 20:30
default_principal_expiration = 20120727203000

Abbreviations used in this document

month : locale’s month name or its abbreviation;
dd : day of month (01-31);
HH : hours (00-12);
hh : hours (00-23);
mm : in time - minutes (00-59); in date - month (01-12);
N : number;
pp : AM or PM;
ss : seconds (00-60);
tt : time units (hours, minutes, min, seconds, sec);
yyyy : year;
yy : last two digits of the year;
Z : alphabetic time zone abbreviation;
z : numeric time zone;


  • If the date specification contains spaces, you may need to enclose it in double quotes;
  • All keywords are case-insensitive.