Changes

This lab will show you how to set up a Postfix email server using a Fedora 17 installed PC20 installation.

{{Admon/important|Prerequistites|Your hard drive should Ensure all machines have Fedora 17, 64 bit Live edition already installed.<br />Both host been updated and guest should have all software updated.<br />Ensure that the clocks on both machines are set to the correct date and time.}}

*Ensure you can surf the web on your host machine. As your host should be using VM 1 as its DNS server, you will need to start it as well.*Ensure you can access the web on your VM02 VM2 (you can use wget or lynx for that). NOTE: you should not have to authenticate yourself on the guest. === Reviewing the mail command === 

===Install and configure Postfixon a VM===*On both machines Vm 2 do the following:**Stop and disable Check the status of the sendmailservice. systemctl If it show up as running or enabled, stop sendmail.service systemctl and disable sendmailit.service**Install Postfixand mail yum install postfixmailx**While that is installing, you may wish to read the mail manual page to remind yourself how it works.**Edit the Postfix configuration file, /etc/postfix/main.cf, and change the following lines ( be sure that there are no other instances of that line as well, comment as needed)parameters:

 {{Admon/important|Warning|Make sure there are no other uncommented copies of these parameters in the file.}} **Create the database file of mail aliases postalias hash:/etc/aliases **Start and enable Postfix on both machines:

 **Check your /var/log/messages file to see that your postfix servers started without error.***If there are any errors, correct them before continuing. ===Testing mail with the internet===*Test email from your machine by sending an email to your Seneca account. mail -s "PART C3" <Your Seneca email address>Note: <Your Seneca email address> is your Seneca email address.<br />Note: after you check type in your letter, enter a period in the first column on the last line and hit the ENTER key.*Check your learn email to see if you got the status of postfixemail (note that it may take a few minutes to arrive, so you may notice also wish to try an alternate email account if you have one). When you do receive that /usr/libexec/postfix/chroot-update exited with email make a status note of 1 (failure)the return address. This is a known issue and *If you did not receive the mail, check the mail logs on your machine to determine what the error is 'harmless'. It will not prevent postfix *Test email from workingthe host by sending an email to your Seneca account. If mail -s "PART C4" -r hacker@evil.com <Your Seneca email address><br />Note: after you wishtype in your letter, enter a period in the first column on the last line and hit the ENTER key.*Check your Seneca email to see if you can [[https://bugzillagot the email.redhatIf you did make a note of the return address.com/show_bug*Repeat the steps for 'Install and Configure Postfix on a vm' on your VM 3.cgi?id=832742 read more about it ]]

*If you have problems with the following adjust Adjust your firewall to allow traffic to/from port 25on both VMs.**Also check your /var/log/maillog file to see the log entries that get created when mail is sent and received, and when something goes wrong.*Try sending an email from vm02 vm2 to your hostvm3. mail -s "PART E2" yyyyyy@[192.168.X.14]

*Try sending an email from your host vm3 to vm02vm2. mail -s "PART E3" zzzzzzroot@[192.168.X.3] Note: zzzzzz is your Seneca ID<br /> 

For this part make sure *Use the host and hostname commands to check that each of your f17 machine machines has a correct host name - f17.yourdomain.orgthe same hostname that the DNS service says they have.**Restart postfix if you change thisthe hostname on either mail server.

Now try sending mail to yourself on both machines. For example, as <senecaID> on f17VM 3, use the command: $ mail <senecaID>@vm02vm2.<yourdomain>.org

#Create a copy of your main.cf file on vm02 (your guest) with this lab - but delete all commented and blank lines first - like this. [cat /etc/postfix/main.cf | grep -v ^# | awk 'NF > 0 {print $0}']Exploration questions:#What is did changing the output of the iptables-save command on both your host and guest machinesrelay_domains parameter do?#What firewall rule or rules, if any, did you have to enter on the guest and/or host so that email to/from each other between your VMs would work?

#What were the results of sending email between the host and the vmVMs? Show log segments to verify your answers.