How can I tell if I have an open relay? [closed] - smtp

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I'm trying to work out if I have an open relay on my server. How do I do that?
I've tried http://www.abuse.net/relay.html
and it reports:
Hmmn, at first glance, host appeared to accept a message for relay.
THIS MAY OR MAY NOT MEAN THAT IT'S AN OPEN RELAY.
Some systems appear to accept relay mail, but then reject messages internally rather than delivering them, but you cannot tell at this point whether the message will be relayed or not.
What further tests can I do to determine if the server has an open relay?

Eh? As your link tells you, register for the site and it will give you an address #abuse.net, valid for 24 hours. Enter that address into the testing form. If your abuse.net account receives the test email, you have an open relay.

You could try setting up a email client to sent email through your server, from an email address that isn't hosted on the same server. If you can successfuly send mail, from an email address at a different domain, without entering a login and password for your SMTP server, then it's probably an open relay.

This depends on your MTA and how you've configured it. Ultimately there is only one thing you must do to prevent relaying. Restrict relaying to authenticated users and/or restrict relaying to specific IPs. I prefer to restrict all IPs except localhost on my mail server and require authentication from everyone else.
The common mistake is to allow more IPs than necessary. Imagine a user on a cable modem who decides to allow the roommate's laptop to relay with the statement 192.168.1.0/24 rather than the more specific 192.168.1.0/29. Now anyone else on the /24 can relay off the server.

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Apache Domain Registering [closed]

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I'm making a website using Apache as the web server. Would I have to register a domain with someone like godaddy? I don't want someone like godaddy hosting a website for me. I want to be in control of the server.
GoDaddy can, but does not have to control the domain itself.
When you register the domain name, you provide GoDaddy (or whichever registrar you choose) multiple "Name Server" addresses. These are the computer systems that will actually house your domain's information.
I use Amazon's Route 53 DNS server (http://aws.amazon.com/route53/) since I run my own web server, but you could run your own DNS server, or use your hosting provider's name servers.
The "Name Server" that you specify will maintain the details about your domain such as what IP handles email, name servers, a/cname records (sub-domains), etc...
In addition to GoDaddy, you could use Network Solutions (http://www.networksolutions.com), Dotster (http://dotster.com), Register.com (http://www.register.com), and if you google DNS Registrars, you'll find tons of them.
You could just buy the domain name from GoDaddy, or any other DNS provider.
You can host your own domain by pointing the nameservers to your own server!
Take a look at How to assign a domain name to your home web server.

local smtp server to send mail [closed]

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i need to demo an application on my laptop running windows 7 enterprise. The application is supposed to send mail. How can i setup a local smtp server to send mail from and be able to recieve it in my outlook on the machine. I need to be able to do this while not connected to the internet for the demo.
Local smtp only: smtp4dev (similar to papercut)
The application catches everything sent to it, but does not send emails over the internet.
XMail or hMailServer should do the trick.
More details on this previous question.
Papercut is pretty active (last release on Jun 25, 2015):
Ever need to test emails from an application or web site but don't want them accidently being sent or having to deal with the hassle of setting up a test email server? Papercut is a quick email viewer with a built-in SMTP server designed to only receive messages. It doesn't enforce any restrictions how you send your email. It allows you to view the whole email-chilada: body, html, headers, attachment down to the naughty raw bits. It can be set to run on startup and sits quietly minimized in the tray giving you a balloon popup when a new message arrives.
You can also try smtp4dev:
A dummy SMTP server for Windows, Linux, Mac OS-X (and maybe elsewhere where .NET Core is available)
You can also (for a demo) user the 'specifiedPickupDirectory' setting to leverage the same code, but drop the email message off to a local folder, alleviating the need for an actual SMTP server, but being able to demonstrate that the email is generated as expected.
MSDN: http://msdn.microsoft.com/en-us/library/ms164241.aspx
As for me the best option is
https://www.npmjs.com/package/maildev
A painless smtp server running on node. Therefore you need to install node, but it actually send an email to any smtp server.
You can send email using Telnet or implement the protocol using socket programming.
Refer to http://www.softwareandfinance.com/Visual_CPP/TelnetEmail.html

Web Host DNS - How Does It Identify Your Account? [closed]

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Today, I signed up for a web host at JustHost, and registered for my domain name at NetFirms. JustHost told me to enter NS1.JUSTHOST.COM and NS2.JUSTHOST.COM as my DNS Namespace at NetFirms to redirect the website to point to my JustHost server. My question is how would NetFirms understand which account at JustHost is mine as I provided a general address that did not contain any information about my account?
I apologize if I have used any incorrect terminology as I don't quite understand exactly how the internet works yet.
What you entered is the DNS server information. The web hosting company already know which IP address(es) they put you on, and that's all that DNS does; resolve host names to IP addresses (and vice versa, if they set you up properly). The domain registrar doesn't care where your web server is (or even what sort of services you offer; it could be SMTP, or IMAP, or several, or none at all); all they need to know is where to send those who want to ask.
Once someone who obtained your IP address from the DNS server connects to the www server on that IP address, the client sends the URL it is requesting, which is then resolved by the server. (The original HTTP spec didn't include the host name part of the URL in the request, so technically the request puts the host name part in the Host: attribute if the request, not the main request line. I don't imagine this detail has any significance for you, but in case you will be reading up on virtual hosting, this might help understand it.)
I would comment this, but I don't have the option to yet.
Does Justhost give you an option to add in a hosted domain? Once you point the DNS to Justhost, you should just be able to add in the domain as a hosted domain on Justhost and it should work from there. (It may take up to 24 hours as the DNS change propogates).

Reason for gmail spamming emails from my server? [closed]

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I have been using some SMTP server for sending mails to gmail server. The problem i am facing is all the mails from a particular domain(say ...#somedomain.info) are treated as Spam by gmail. Is there any way to solve this issue?
Have you analyzed your outgoing mails? What SpamAssassin score do they get if you send them to a server with a SpamAssassin filter?
Normally your issue indicates a wrong mail server setup. Wrong DNS setup, blacklisted on DNSBLs, invalid DKIM or SPF setup, invalid headers or mail encoding, ...
But at first you have figure out what the root cause is. You only stated the impact. And SpamAssassin tests hundreds of rules for many common mail problems. So knowing the rules that get hit lead to finding the cause(s).
If you like you could write a mail to mailtest[AT]malowa.de and I will analyze the score.

capture the Failure mail [closed]

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Is it possible to capture the failure mail. I have created a application for sending mail, i have a log file to store the sent mails. If the sent mail is failure, i just want to find out the failure mail and update the log file.
Is it possible! Is there any way to match the sent mail and the failure mail
Please help me and guide me.
If you mean by failure, a bounced email, you can add an email address to 'return-path' header. If the email is bounced it will be returned to the the email address specified in the return-path. You can then set up a service to analyze these emails.
You have to specify what client are you using, is it Postfix, sendmail, etc?
And what do you mean by "failure".
The basic approach would be to use crontab. It can direct error message
to your email, when it fails
MAILTO=youremail#foo.net
#
# run five minutes after midnight, every day
5 0 * * $HOME/bin/emailcode
If you use sendmail, you can always
verify the log at:
/var/log/maillog