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questions on sendmail


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.


1 Solution
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 http://www.redhat.com/support/docs/mail.html
fokchiAuthor Commented:
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?
in linuxconf COnfig / Netowrking / Server / Mail Delivery system / Anti-Spam filters

or check out /etc/mail/ip-allow afterwhich you must restart sendmail.
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fokchiAuthor Commented:
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.  
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.

the fact that you cand send mail from any machine is news to me - I thought the default (RH) sendmail.cf 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.

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.


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