The main configuration file for Sendmail is /etc/mail/sendmail.cf , which is not intended to be manually edited. Instead, make any configuration changes in the /etc/mail/sendmail.mc file.

Where is sendmail on Ubuntu?

Install and configure Sendmail on Ubuntu

1. If sendmail isn’t installed, install it: sudo apt-get install sendmail.
2. Configure /etc/hosts file: nano /etc/hosts.
3. Make sure the line looks like this: 127.0.0.1 localhost yourhostname.
4. Run Sendmail’s config and answer ‘Y’ to everything: sudo sendmailconfig.

How do I enable sendmail?

So, the steps I recommend for configuring sendmail are as follows:

1. Edit the /etc/sendmail.mc file. Most of what you need to do to configure sendmail can be done by editing this file.
2. Generate the sendmail.cf file from the edited sendmail.mc file. …
3. Review your sendmail.cf configuration. …
4. Restart the sendmail server.