Find IP addresses from logs

 To search given pattern 
   |
   |	Asterik character is use to	The backward slash is a escape character
   |    match anything or none. In	which is use to know the shell that given
   |	this there may be two more	character is not a part of regurlar
   |	number in each octet or		expression or in other words avoid to use
   |    none.	                        as regular expression. Dot is a one kind 
   |	     |                 _________of regular expression which use to match
   |	     |                |		any but not empty.
   |	     |                |
# grep '[1-9]*\.[0-9]*\.[0-9]*\.[1-9]*' /var/log/syslog
        |   |   |   |   |   |   |   |
        |___|   |___|   |___|   |___|
        |       |       |       |
        |       |       |       |
 Range are declared by putting dash - character in
 between numbers from 1 to 9 for the first and the
 fourth octet and 0 to 9 for the second and third
 octet of IP address. In first and fourth octet
 First number would be higher than zero and in the
 second and third octet first number can be 0 or
 higher than zero.