Unit 3 Assignment 1 Sendmail Pdf
Email is an important part of any Web site you create. In a home environment, a free web based email service may be sufficient, but if you are running a business, then a dedicated mail server will probably be required.
This chapter will show you how to use sendmail to create a mail server that will relay your mail to a remote user's mailbox or incoming mail to a local mail box. You'll also learn how to retrieve and send mail via your mail server using a with mail client such as Outlook Express or Evolution.
Configuring Sendmail
One of the tasks in setting up DNS for your domain (my-site.com) is to use the MX record in the configuration zone file to state the hostname of the server that will handle the mail for the domain. The most popular Unix mail transport agent is sendmail, …show more content…
Determine which NICs sendmail is running on. You can see the interfaces on which sendmail is listening with the netstat command. Because sendmail listens on TCP port 25, you use netstat and grep for 25 to see a default configuration listening only on IP address 127.0.0.1 (loopback): [root@bigboy tmp]# netstat -an | grep :25 | grep tcp tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
[root@bigboy tmp]# 2. Edit sendmail.mc to make sendmail listen on all interfaces. If sendmail is listening on the loopback interface only, you should comment out the daemon_options line in the /etc/mail/sendmail.mc file with dnl statements. It is also good practice to take precautions against spam by not accepting mail from domains that don't exist by commenting out the accept_unresolvable_domains feature too. See the fourth and next to last lines in the example. dnl This changes sendmail to only listen on the loopback device 127.0.0.1 dnl and not on any other network devices. Comment this out if you want dnl to accept email over the network. dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA') dnl NOTE: binding both IPv4 and IPv6 daemon to the same port requires dnl a kernel
This chapter will show you how to use sendmail to create a mail server that will relay your mail to a remote user's mailbox or incoming mail to a local mail box. You'll also learn how to retrieve and send mail via your mail server using a with mail client such as Outlook Express or Evolution.
Configuring Sendmail
One of the tasks in setting up DNS for your domain (my-site.com) is to use the MX record in the configuration zone file to state the hostname of the server that will handle the mail for the domain. The most popular Unix mail transport agent is sendmail, …show more content…
Determine which NICs sendmail is running on. You can see the interfaces on which sendmail is listening with the netstat command. Because sendmail listens on TCP port 25, you use netstat and grep for 25 to see a default configuration listening only on IP address 127.0.0.1 (loopback): [root@bigboy tmp]# netstat -an | grep :25 | grep tcp tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
[root@bigboy tmp]# 2. Edit sendmail.mc to make sendmail listen on all interfaces. If sendmail is listening on the loopback interface only, you should comment out the daemon_options line in the /etc/mail/sendmail.mc file with dnl statements. It is also good practice to take precautions against spam by not accepting mail from domains that don't exist by commenting out the accept_unresolvable_domains feature too. See the fourth and next to last lines in the example. dnl This changes sendmail to only listen on the loopback device 127.0.0.1 dnl and not on any other network devices. Comment this out if you want dnl to accept email over the network. dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA') dnl NOTE: binding both IPv4 and IPv6 daemon to the same port requires dnl a kernel