The main documentation for configuring sendmail is in a file at sendmail/cf/README. For some reason it isn't here on my 18.04 server.
Note that this file is referred to in other documentation within the sendmail/cf directories.
The main documentation for configuring sendmail is in a file at sendmail/cf/README. For some reason it isn't here on my 18.04 server.
Note that this file is referred to in other documentation within the sendmail/cf directories.
Have you installed the sendmail documentation package?
sendmail-doc
https://packages.ubuntu.com/bionic/sendmail-doc