The following questions will help you measure your understanding of the material presented in this chapter. As no multiple choice questions appear on the Red Hat exams, no multiple choice questions appear in this book. These questions exclusively test your understanding of the chapter. It is okay if you have another way of performing a task. Getting results, not memorizing trivia, is what counts on the Red Hat exams. There may be more than one answer to many of the questions.
1. | What package described in this chapter can be configured for incoming POP3 and IMAP4 e-mail? _______________________________________________ |
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1. | The package that can be configured to receive POP3 and IMAP4 e-mail is Dovecot. |
2. | If you don't want to allow secure incoming e-mail, what would you do with the following directive in /etc/dovecot.conf?
#protocols = imap imaps pop3 pop3s _____________________________________________________________ |
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3. | What script should you use to configure an SSL certificate for Dovecot? _____________________________________________________________ |
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4. | What certificate files do you need to move or delete before creating a customized SSL certificate? _____________________________________________________________ |
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2. | If you don't want to allow secure incoming e-mail (for whatever reason), you need to activate and change the protocols directive to specify only the nonsecure e-mail protocols:
protocols = imap pop3 |
3. | The script that helps configure an SSL certificate for Dovecot is mkcert.sh, in the /usr/share/ doc/dovecot-1.0/examples directory. |
4. | The certificate files that you need to move or delete before creating a customized SSL certificate are both named dovecot.pem, in the /etc/pki/dovecot/certs and /etc/pki/dovecot/private directories. |
5. | In what file would you store forwarding e-mail addresses? _____________________________________________________________ |
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6. | Why would you want to comment out the following directive in sendmail.mc?
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl _____________________________________________________________ |
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7. | What do you need if you want to comment out the following directive in sendmail.mc?
FEATURE(`accept_unresolvable_domains')dnl _____________________________________________________________ |
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8. | What command processes all files in /etc/mail? _____________________________________________________________ |
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5. | Forwarding e-mail addresses for both sendmail and Postfix are normally stored in /etc/aliases. If you're forwarding e-mail for entire domains, the appropriate file is /etc/mail/domaintable. Make sure to process these files into appropriate databases; for /etc/aliases, the database is updated with the newaliases command. For /etc/mail/domaintable, the database is updated with the next make -C /etc/mail command. |
6. | The noted directive limits sendmail server access to the localhost computer, IP address 127.0.0.1. |
7. | If you don't want to accept unresolvable domains, say to minimize spam on your system, you'll need reliable DNS service. Otherwise, reverse DNS searches may fail, and your system may not accept even legitimate e-mail. |
8. | The make -C /etc/mail command processes all files in /etc/mail, including sendmail.mc, submit .mc, and the database files in that directory. It does not process any forwarding aliases in /etc/ aliases; if you make a change to this file, you need to use the newaliases command. |
9. | How would you change the following directive in /etc/postfix/main.cf to open Postfix to all systems?
inet_interfaces = localhost _____________________________________________________________ |
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10. | If you use /etc/aliases for forwarding e-mail, what command processes these files into an appropriate database file for Postfix? _____________________________________________________________ |
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9. | The simplest solution is to change the directive to
inet_interfaces = all |
10. | Forwarding e-mail addresses for both sendmail and Postfix are normally stored in /etc/aliases. Make sure to process these files into appropriate databases; for /etc/aliases, the database is updated with the newaliases command. |
11. | What command allows you to select between the Postfix and sendmail servers? _____________________________________________________________ |
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12. | What command line e-mail client can you use to test a server? _____________________________________________________________ Extra Credit: What can you run directly from the command line to send a simple test e-mail? _____________________________________________________________ |
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11. | There are a wide variety of solutions to this problem. The simplest solutions are fastest and best. Two simple commands can help you switch between Postfix and sendmail: alternatives --config mta and system-switch-mail. |
12. | Several command-line e-mail clients are available for RHEL, including mutt and mail. Extra Credit: One simple way to send a message with the mail client is with the following command (variations are acceptable, as the point is to check the e-mail server quickly from a remote location). The e-mail subject in this case is test subject and the message is hello kitty.
# echo "hello kitty" | mail -s "test subject" michael@enterprise5a Once the message is sent, you can confirm in the mail spool for the user and the log file for the server. |