Problems with mail

Support & Help Requests
1

Can not get mail to work. ?

mail -s "Hello World" [email protected]
test
andy@7:~/Downloads$ sendmail: warning: valid_hostname: numeric hostname: 7
sendmail: fatal: unable to use my own hostname
2

Ever since I install mail-utils, I have all kinds of problems.

I uninstalled it with no luck. I need this problem fixed.

I get this AFTER it’s uninstallation when I run update, clean, and autoremove.

postconf: warning: valid_hostname: numeric hostname: 7
postconf: fatal: unable to use my own hostname
Use of uninitialized value $destinations in scalar chomp at /var/lib/dpkg/info/postfix.config line 221.

Use of uninitialized value $_[1] in join or string at /usr/share/perl5/Debconf/Client/ConfModule.pm line 121.
postconf: warning: valid_hostname: numeric hostname: 7
postconf: fatal: unable to use my own hostname
dpkg: error processing package postfix (–configure):
subprocess installed post-installation script returned error exit status 1
Processing triggers for libc-bin (2.23-0ubuntu9) …
Errors were encountered while processing:
postfix
E: Sub-process /usr/bin/dpkg returned an error code (1)

This is in mail.log

Jan  3 17:08:02 7 postfix/sendmail[6178]: warning: valid_hostname: numeric hostname: 7
Jan  3 17:08:02 7 postfix/sendmail[6178]: fatal: unable to use my own hostname
3

Why did you install this? do you run a mail server on your machine?

Also, I can’t find a mail-utils package in the Ubuntu 17.10 repos, nor on packages.ubuntu.com for any supported version. Did you mean mailutils (I assume it’s the case but there exists an ax25mail-utils so I prefer to ask)?

4

I installed it based on a site that showed 5 ways to send an email from a terminal.

It said nothing about an mail server on my computer ?

I am using 16.04. It’s in Package Manager.

mailutils
GNU mailutils utilities for handling mail

Any way I can remove it from PPM?

5

Well, it's kind of implied, as to use the mail command, you need to have a properly configured mail server. I guess you can use an external one (like the one from your ISP) but it'd have to be configured manually anyway.

You can try the following:

sudo apt-get install --reinstall mailutils
sudo apt-get remove --purge mailutils mailutils-common

This will reinstall (if possible) the mailutils package and then remove it again but this time including the configuration files (--purge option). Hopefully, this will fix the issue with the configuration of postfix. If not, we'll need to go deeper.

6

thanks for your patience. :slight_smile:

Think I have it fixed.

In hostname
# used to be 7 changed to k on 1/4/18
k

I think mail did not like digits.

When I installed UM, it asked for user and I picked andy.
Then it ask for something else and I picked 7.

Now it is ‘k’

I no longer get any error messages when running apt update etc.

But I have learned and will never use the mail command. :slight_smile:

Will stick to using Seamonkey for sending emails.

7

I think mail did not like digits.
When I installed UM, it asked for user and I picked andy.
Then it ask for something else and I picked 7.
Now it is 'k'

7 is indeed quite a peculiar name for a machine. I'm surprised it would accept it at all (even though, in theory, I guess that nothing forbids this).

For information, the "something else" it asked you to pick is the hostname, the name of your machine on the network. It's not really important if you only have one machine on your local network (yet, these days, a lot of people have multiple machines, even in the form of smartphones and tablets) but it's used by softwares related to the network in general, like mail.

8

Thanks for the explanation.