I want to send a simple E-mail notification (just an alert) from a bash script and came across mail, but there still you need to configure a mail server and I have not found any good tutorial on that. So is there another way to simply send an E-mail to my a gmail adress from the command-line using only my localhost?
Using Ubuntu 20.04
I would like to be able to send emails in command line and in bash scripts (e.g., to get notifications about running simulations on my computer). There are apparently different options to do that, but all seem to rely on postfix. However, as far as I understand it, postfix is a full email client to send and receive emails. In my case, I am just interested in sending emails.
I am particularly worrying about security issues and I don't want to open any doors on my system by installing one of these programs.
Any advice on how to configure postfix to only allow outgoing emails and to block anything else to avoid any threats? Or any other ideas to send emails securely?
Many thanks for your help!
PS: Running Ubuntu 14.04.01 LTS.
I am looking for a single line email notification solution for linux, but one that would not assume that the machine mail agent was already configured properly.
I want to specify the SMTP server from the command.
Preferably, the solution should run on Debian without having to install new tools.
For our web projects, we need a reliable e-mail distribution mechanism. Due to bad experiences in the past, I have written a bash script (executed hourly) which sends a notification e-mail if
the qmail-send process is not running
there are too many failures in the mail log
For sending the notification e-mail I obviously don't want to depend on qmail, since qmail will be unavailable if the qmail-send process is not running. However, the following command sends the notification e-mail via qmail:
echo "failure rate critical" | mail -s "qmail notification" my#email.com
What's the easiest way to send e-mail from the linux command line without qmail? Can I use sendmail?
If you guys have smarter alarm systems to monitor qmail, please let me know.
Invoke the /usr/sbin/sendmail binary. It is usually available no matter which MTA you use and you can be sure it supports the standard sendmail interface if it's named sendmail.
The easiest way to use it is invoking sendmail -t and then writing the email including a valid To header to its stdin. If you omit -t you'll have to pass the recipient address as a commandline argument.
Another solution would be using SMTP but if you need to send emails from a bash script this is clearly a bad solution as there are no standard libraries in Bash which contain functions to send an email over smtp (unlike in python where you cannot easily send mails using sendmail but over SMTP).
You have a mail utility in POSIX. If you're only for linux, sendmail is ok (but then you rely on the system's (mis)configuration, right?).
All in all, SMTP protocol is not that difficult. I'd say you can talk in pure SMTP. It's about four commands to issue for a trivial mail. And it's portable:)
But if there are complications it may result in PITA...
I have a computer at home which I can't access from work. I'd like to be able to view results from work that my home computer produces. The best idea I've come up with is an automated script running on my home computer that emails myself the results (from a text file or stderr/out) when complete.
I'm decent with bash (I have a linux machine) and java, so an answer using either or both of those would be ideal, but if there's something easier that's fine too.
I typically use gmail, but also have yahoo mail.
My question is this: what would be the basic steps in solving this problem? I can do the nitty gritty stuff, but can't really get the big picture of how something like this would work.
Please help.
jbu
Howto set up ssmtp to send through a Gmail account
Some of the steps here might seem strange at first, but the rationale is put
in footnotes that should hopefully explain why.
First create a spare account on gmail which you will only use for
sending email. For instance, if your normal account is user#gmail.com,
create an account user.noreply#gmail.com with a newly created password
which you only will use for this account [1].
Set up the new account to forward all email to the normal account [2]
and under account settings you should add all other email adresses you
use [3].
Then install ssmtp (On Debian: aptitude install ssmtp) and edit ssmtp's configuration file /etc/ssmtp/ssmtp.conf:
root=user#gmail.com
mailhub=smtp.gmail.com:587
UseSTARTTLS=YES
AuthUser=user.noreply
AuthPass=passwdusedonlyforthisaccount
FromLineOverride=YES
and configure the local mail delivery by editing /etc/ssmtp/revaliases
assuming that your local login is localuser:
root:user#gmail.com:smtp.gmail.com:587
localuser:user#gmail.com:smtp.gmail.com:587
Make sure the two configuration files are readable to all users who
should be able to send email [4].
Test the setup by e.g. mailx (On Debian: aptitude install bsd-mailx):
echo 'testing, one, two' | mailx -s 'test 1' user#gmail.com
Hope this helps.
[1] The new gmail user name and password will be visible to everyone who
can log onto your machine, so you do not want this account to be
critical in any way, meaning you can close it down immediately if
someone should get access to it.
[2] If some email you sent bounces back to you, you might want to know
about it, and there actually exists people who will happily reply to an
email from johnsmith.noreply.
[3] Gmail will rewrite the From header on the email if it does not recognise the address.
[4] Ssmtp runs as the local user who sends the email, so that user needs
read access to the configuration files.
On any Linux I have used the mail sending from command-line is simple:
mail -s "My subject here" recipient#wherever.com <message_body.txt
AFAIK this acts as a front-end to sendmail, and you have to have sendmail configured to forward the messages to your ISP mail server.
You can't access your home computer from work which rules out a "remote support" option.
Can you access other computers on the Internet? If so, you could simply set up one of the online storage options and then ftp the results from your home computer. That's a lot simpler then trying to write scripts or code to generate emails with attachments or whatever.
You could then view the external computer from work.
If you have netcat, this command will send you an e-mail:
Given a file in this format (from Wikipedia):
HELO relay.example.org
MAIL FROM:<bob#example.org>
RCPT TO:<alice#example.com>
RCPT TO:<theboss#example.com>
DATA
From: "Bob Example" <bob#example.org>
To: Alice Example <alice#example.com>
Cc: theboss#example.com
Date: Tue, 15 Jan 2008 16:02:43 -0500
Subject: Test message
Hello Alice.
This is a test message with 5 headers and 4 lines in the body.
Your friend,
Bob
.
QUIT
Then netcat it to an SMTP server you have access to:
nc mail.somewhere.com 25 < file.txt
This will then send the e-mail. You can see how you can create a Java program to do this for you (just execute the commands).
Traditionaly, with unix systems like Linux, you'd have an MTA, a mail transfer agent, on the computer that deals with sending e-mail.
This could be a full blown e-mail server like exim, or something simple like ssmtp that just sends messages on to a relaying SMTP server such as would be provided by your ISP.
This isn't neccessarily the case anymore, since mail clients like Thunderbird include their own MTA, much like mail clients on Windows do.
However, it is likely that your distro will install some MTA or other by default, if for no other reason than the fact that other things on your system, like cron, want to be able to send e-mail. Generally there will be a command line tool called sendmail (sendmail being the original MTA [citation needed], other MTAs maintain compatability with its interface and it has sort of become the standard) that can be used from a shell script to send an e-mail.
My solution assumes that you have a SMTP server available which allows you to send an email programmatically. Alternatively, you can use a local install of sendmail which generally is available with most linux distros.
Create a standalone java program which watches the directory your home computer saves the file to. Use the JavaMail API to attach and send the file to any email you wish.
If you're also familiar with the Spring Framework, it has a nice abstraction layer for working with JavaMail and makes this sort of thing trivial.
Of course, your home ISP probably has the common SMTP port blocked as well.