questions on sendmail

Posted on 2000-03-20
Last Modified: 2011-09-20

I am totally new to sendmail and I have couple questions on that:

1. I am trying the sendmail on my Redhat Linux 6.1. I use rpm to install it.  It is working ok so far for me. I mean I can send and recieve email from that local linux computer. However, when I want to use Netscape,as MUA, of another Windows 98 machine to read my email from that Linux machine, it just don't work for me! I wonder there are some config file I need to change in the sendmail before I can do the remote mail retrival. Is anyone can show me how to do that step by step?

2. I have another question on the SMTP daemon. I know the smtp daemon is running on my linux server. I tried to use this smtp daemon in my linux server to send email. It works without asking me for any password for that! I'm worry about the security issue. In that case, anyone can use my server to send mail as long as they know I have sendmail install on my linux, right? Is that anything I can do to set it just for specfic range of my domain to send email by using the smtp server?

3. I read some linux books for sendmail. Most of them said "sendmail" is not easy to admin and config. What is your opinion on that? They recommand "Smail" for beginner instead. Is that really the case? Those book I read is quite old. I wonder if that is still the case for Redhat Linux 6.1?

I know I have too much question for you. But I will more than apprciate, if you can help me to solve my problem on sendmail.


Question by:fokchi
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
LVL 12

Expert Comment

ID: 2639566
1. You need pop installed aswell. try "telnet localhost 110" unless you get something like "+OK POP3 localhost v7.60 server ready" you do not have a pop server, and no clients will be able to poll mail from the server. Just install the rpm and you are set.

2. Yes, that is tru, this is where SPAM comes from. Use the  "Anti Spam Filter" in linuxconf to fix this. Ethier add the network number of your internal net to the "Relay for by IP" (if you are using 192.168.0.x internally, add 192.168.0. here (note the last . _must_ be there). Or set up a local DNS and use the relay for by name.

3. Also true, sendmail is massive, but linuxconf hides most stuff from the user, and works well, smail is simpler, but RH doesnt oficially support this, so you would ahve to remove sendmail manually, aswell as install / config / modify the redhat to cater for smail. Then again, over 85% of all systems still use sendmail.

Also redhat provides you with this

Author Comment

ID: 2639603
Thanks j2,

But, I just can't find the Anti Spam Filter in linuxconf. Also, what is the file in sendmail do this relay for by IP job?
LVL 12

Expert Comment

ID: 2639952
in linuxconf COnfig / Netowrking / Server / Mail Delivery system / Anti-Spam filters

or check out /etc/mail/ip-allow afterwhich you must restart sendmail.
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!


Author Comment

ID: 2639977
I tried that. Now I can read email from other machine. But, the problem is I can use any machine to send email. I try to use linuxconf to restrict it, it don't work. And I just can't find the  ip-allow file anywhere in the linux.  
LVL 12

Expert Comment

ID: 2639988
1. Exactly _what_ did you try?
2. Exactly _what_ does not work?

the filename is /etc/mail/ip_allow sorry about that. if it isnt there, create it, it is just a list of network numbers.

Expert Comment

ID: 2641007

the fact that you cand send mail from any machine is news to me - I thought the default (RH) came with just local relay set up - no , actually I know it for a fact that applies to at least 8.9.2, but maybe they changed it in RH6.1.

The book you read is indeed old - smail is dead in the water AFAIK. Sendmail is not your piece-of-cake MTA, but redhat does a pretty decent job of setting it up alright for single-user, and extending it to a small LAN will not be very difficult.

Qmail and postfix are more modern and easier to configure, however, I wonder if you'll find the same support as sendmail (both on the 'net and in RH) for setting them up. If the answer is 'no', then they may wind up in being actually *more* difficult to set up and mange at your level of experience and needs.

And, for the record, if I were switching MTAs I'd go with PostFix - if only because Wietse is the author.


Accepted Solution

mapc earned 100 total points
ID: 2644287
First of all, I'm with 'alien_life_form'- postfix is more secure, is faster and easier to maintain.
You could also try exim.
it has SMTP AUTH - the send needs user/pass, and is somehow authentificated before sending mail.
For retreiving mail you'll need pop3 server, try qpopper:
or the one which comes from uw:
or GNU pop3d:
or cucipop:
We use qpopper and quite happy with it.
I heard that cucipop is nice.
Your milleage may vary.
Sendmail - smtp listens on port 25
POP3 - listens on port 110
IMPA - listens on port 143.
you could check that in /etc/services.

The software comes with complete documentation, thus I think that the question is answered.


Featured Post

NEW Veeam Agent for Microsoft Windows

Backup and recover physical and cloud-based servers and workstations, as well as endpoint devices that belong to remote users. Avoid downtime and data loss quickly and easily for Windows-based physical or public cloud-based workloads!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I have seen several blogs and forum entries elsewhere state that because NTFS volumes do not support linux ownership or permissions, they cannot be used for anonymous ftp upload through the vsftpd program.   IT can be done and here's how to get i…
Note: for this to work properly you need to use a Cross-Over network cable. 1. Connect both servers S1 and S2 on the second network slots respectively. Note that you can use the 1st slots but usually these would be occupied by the Service Provide…
Finding and deleting duplicate (picture) files can be a time consuming task. My wife and I, our three kids and their families all share one dilemma: Managing our pictures. Between desktops, laptops, phones, tablets, and cameras; over the last decade…

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question