sendmail

Question 1

What is the name of the main executable that receives messages from local and remote users and determines how to delivery those messages?

Answer 1

sendmail

Question 2

The name of the main sendmail configuration file

Answer 2

sendmail.cf (Usually in /etc/mail/sendmil.cf)

Question 3

Configuration file that contains a list of domains sendmail will receive messages for

Answer 3

sendmail.cw

Question 4

Configuration file that contains a list of trusted users of the sendmail service

Answer 4

sendmail.ct

Question 5

Filename of a file that contains a list valid recipient names that can redirect to a user, program or file

Answer 5

aliases

Question 6

After editing the aliases file, what command should you run?

Answer 6

newaliases

Question 7

What sendmail command can you run to check the mail queue

Answer 7

mailq

Question 8

In which directory does sendmail store message awaiting delivery?

Answer 8

mqueue

Question 9

Which file is used to allow overriding for specific domains?

Answer 9

mailertable

Question 10

What is the domaintable file used for?

Answer 10

to map old domain names to new ones

Question 11

What is the purpose of virtusertable

Answer 11

It is used to map users and domains to alternate addresses

Question 12

What is relay-domains used for?

Answer 12

To allow specific hosts to relay messages through the sendmail server

Question 13

What is the access file used for?

Answer 13

To allow or deny access to sendmail from specific domains.

Question 14

The sendmail.cf file consists of rule sets that parse messages and determine what action to take. These rules have helper functions, what are the 3 types of helper functions

Answer 14

Classes - common phrases that are used to identify message types.
Macros - long string values that are set to simplify typing
Options - defined to set parameters

Question 15

What is m4 processor?

Answer 15

It’s a helper program that allows you to create a sendmail.cf file from a simpler file of macros.

Question 16

How would you create a sendmail config file from an m4 macro file name myserver.mc?

Answer 16

m4 < myserver.mc > /etc/mail.sendmail.cf

Question 17

What does this command do?

sendmail -bd -q5m

Answer 17

This command will start the sendmail server as a background daemon (-bd), that will check the mail queue every 5 minutes (-q5m)