sendmail server

deep27ak · 12-28-2011, 12:31 AM

Hello everyone

I have sucessfully configured sendmail in my machine i.e RHEL 5.2 and I am able to sendmails within my box to all the users.
I am using smtp.gmail.com for my smtp server with ip address 192.168.0.195

But now I want to use this machine 192.168.0.195 to act as smtp server for my other linux client machines so that the clients can send mails to each other using this smtp server (192.168.0.195)

Please let me know what changes do I need to make and where to start from?

bathory · 12-28-2011, 02:30 AM

Hi,

You should add your clients hostnames and/or IPs in /etc/mail/access, like that:

Code:

clientA.domain.com RELAY
x.x.x.x RELAY

After that you need to hash the file to create the access database:

Code:

makemap hash /etc/mail/access < /etc/mail/access

See this and this for more details and options.

Regards

deep27ak · 12-28-2011, 03:46 AM

Yes I did that but no success

Once I send a mail I get a success output

Code:

Dec 28 17:58:00 server sendmail[9815]: pBSCS0Ux009815: to=<root@server.example.com>, delay=00:00:00, xdelay=00:00:00, mailer=local, pri=31548, dsn=2.0.0, stat=Sent

but the message is not received at the end.

Let me tell you the domain is not registered. Can you guide me how to register a domain to create my own smtp server?

bathory · 12-28-2011, 05:29 AM

Quote:

Once I send a mail I get a success output

Dec 28 17:58:00 server sendmail[9815]: pBSCS0Ux009815: to=<root@server.example.com>, delay=00:00:00, xdelay=00:00:00, mailer=local, pri=31548, dsn=2.0.0, stat=Sent

but the message is not received at the end.

If server.example.com is your sendmail server, you should look at its logs to see what happens. Perhaps it stays in queue because the server does not know where to deliver.

Quote:

Let me tell you the domain is not registered. Can you guide me how to register a domain to create my own smtp server?

what you mean by that? You can create a fake domain, using a private dns for you and your clients, or you need to register a real domain using a registrar.
Then you have to configure the dns server authoritative for that domain (could be yours or your registrars) and add a MX record that points to your mail server.

jayakumar01 · 12-28-2011, 05:30 AM

Hi,

Few things i had done to divert my traffic to gmail acc

Step1: vi /etc/mail/access
Connect:172.17 RELAY

Step2: vi /etc/hosts

ipaddress fullyqualifieddomainname hostname

Step 3: Check whether ur ipaddress in block list by isp .

.

deep27ak · 12-28-2011, 07:32 AM

Quote:

Originally Posted by bathory

If server.example.com is your sendmail server, you should look at its logs to see what happens. Perhaps it stays in queue because the server does not know where to deliver.

The message output which I posted was from logs

Code:

/var/log/maillog

what you mean by that? You can create a fake domain, using a private dns for you and your clients, or you need to register a real domain using a registrar.
Then you have to configure the dns server authoritative for that domain (could be yours or your registrars) and add a MX record that points to your mail server.

I have configured one DNS server on 192.168.0.195 i.e server.estmail.com with MX record mail.estmail.com and the DNS server is running properly and my client is running on the same dns i.e 192.168.0.195

but still I am not getting positive output

Here is my forward zone file

Code:

#cat estmail.com.zone
$TTL    86400
@               IN SOA  server.estmail.com.             mail.estmail.com.root (
                                        53              ; serial (d. adams)
                                        3H              ; refresh
                                        15M             ; retry
                                        1W              ; expiry
                                        1D )            ; minimum

                IN NS           server.estmail.com.
                IN MX           10 mail.estmail.com.
smtp            In A            192.168.0.195
server          IN A            192.168.0.195
www             IN A            192.168.0.195
ftp             IN A            192.168.0.195

Code:

#cat /etc/resolv.conf
search estmail.com
nameserver 192.168.0.195

Now when I send mail from client to 192.168.0.195 here is the log output

Code:

Dec 29 00:20:32 server sendmail[11443]: pBSIoWkr011441: to=<user1@server.estmail.com>, ctladdr=<root@server.example.com> (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=120303, relay=smtp.estmail.com. [192.168.0.195], dsn=4.0.0, stat=Deferred: Connection refused by smtp.estmail.com.

on the server and client

Code:

#cat /etc/mail/access
# Check the /usr/share/doc/sendmail/README.cf file for a description
# of the format of this file. (search for access_db in that file)
# The /usr/share/doc/sendmail/README.cf is part of the sendmail-doc
# package.
#
# by default we allow relaying from localhost...
Connect:localhost.localdomain           RELAY
Connect:localhost                       RELAY
Connect:127.0.0.1                       RELAY
Connect:192.168.0.195                   RELAY
Connect:10.10.10.98                     RELAY <------- client machine(both are in network)

Can you tell me what all changes do I need to do in my sendmail.mc file to send mails from client to server

my current sendmail.mc

Code:

define(`SMART_HOST', `smtp.estmail.com')dnl
define(`RELAY_MAILER_ARGS', `TCP $h 587')dnl
define(`ESMTP_MAILER_ARGS', `TCP $h 465')dnl

DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

(these are the changes which I have done, Do I need to do any thing else?

Or if possible I can switch to postfix but how am I suppose to configure it to use 192.168.0.195 as my smtp server?

bathory · 12-28-2011, 08:27 AM

Quote:

IN MX 10 mail.estmail.com.

You have a different MX record (mail.estmail.com), than the one you want to use as a mailserver (I guess it''s smtp.estmail.com).

Quote:

my current sendmail.mc
Code:

define(`SMART_HOST', `smtp.estmail.com')dnl
define(`RELAY_MAILER_ARGS', `TCP $h 587')dnl
define(`ESMTP_MAILER_ARGS', `TCP $h 465')dnl

DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

I don't think you need the first 3 lines, as you want to use your sendmail as the smtp server for your network.

Quote:

Dec 29 00:20:32 server sendmail[11443]: pBSIoWkr011441: to=<user1@server.estmail.com>, ctladdr=<root@server.example.com> (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=120303, relay=smtp.estmail.com. [192.168.0.195], dsn=4.0.0, stat=Deferred: Connection refused by smtp.estmail.com

Could be related to the above. Or you should check if port 25 is listening and there is no firewall blocking access to it.

Regards

deep27ak · 12-28-2011, 08:43 AM

My server was not listeneing to port 587 and 465. I did some changes in sendmail.mc and now its listening to both the ports

Now when I send mails from client machine(10.10.10.98--server.example.com) to server this is the log output which I get

Code:

Dec 29 01:35:48 server sendmail[12465]: pBSK5mjH012465: to=<root@server.example.com>, delay=00:00:00, xdelay=00:00:00, mailer=local, pri=31556, dsn=2.0.0, stat=Sent

But still I don't receive any message on 192.168.0.195(server.estmail.com)

I did some changes in zone file

Code:

$TTL    86400
@               IN SOA  server.estmail.com.             mail.estmail.com.root (
                                        59              ; serial (d. adams)
                                        3H              ; refresh
                                        15M             ; retry
                                        1W              ; expiry
                                        1D )            ; minimum

                IN NS           server.estmail.com.
                IN MX           10 mail.estmail.com.
smtp            In A            192.168.0.195
server          IN A            192.168.0.195
www             IN A            192.168.0.195
ftp             IN A            192.168.0.195
mail.estmail.com.       IN A    192.168.0.195

This is the return mail which I get

Code:

Date: Thu, 29 Dec 2011 01:35:48 +0530
From: Mail Delivery Subsystem <MAILER-DAEMON@server.example.com>
To: <root@server.example.com>
Subject: Returned mail: see transcript for details
Auto-Submitted: auto-generated (failure)

[-- Attachment #1 --]
[-- Type: text/plain, Encoding: 7bit, Size: 0.4K --]

The original message was received at Thu, 29 Dec 2011 01:35:48 +0530
from localhost.localdomain [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<user1@server.estmail.com>
    (reason: 530 5.7.0 Authentication required)

   ----- Transcript of session follows -----
... while talking to mail.estmail.com.:
>>> MAIL From:<root@server.example.com> SIZE=532
<<< 530 5.7.0 Authentication required
554 5.0.0 Service unavailable

[-- Attachment #2 --]
[-- Type: message/delivery-status, Encoding: 7bit, Size: 0.3K --]

Reporting-MTA: dns; server.example.com
Received-From-MTA: DNS; localhost.localdomain
Arrival-Date: Thu, 29 Dec 2011 01:35:48 +0530

So do you want me to change
mail.estmail.com to smtp.estmail.com ???

bathory · 12-28-2011, 09:11 AM

Quote:

So do you want me to change
mail.estmail.com to smtp.estmail.com ???

Now that you have given an A RR to mail.estmail.com it doesn't matter.
But in general, when someone sends an email to user@estmail.com, the 1st thing that is done, is to find the MX RR for that domain and then connect to that host in order to deliver the mail.

Quote:

(reason: 530 5.7.0 Authentication required)

Somehow you have configured sendmail to require authentication in order to relay mail.
If you have a backup of the sendmail.mc that came with your distro, it should work out of the box, with the only minor change:

Code:

DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

because IIRC by default it listens only on the local loopback interface

deep27ak · 12-29-2011, 07:23 AM

Well I have end up with a result i.e I wont be able to send mails to other linux boxes as my domain is not registered even though they are using same DNS but I am able to send mails to gmail using my smtp server from all the client machines using the same smtp server.

I just mentioned this line in sendmail.mc

Code:

define(`SMART_HOST', `mail.estmail.com')dnl

where mail.estmail.com is MX record in my DNS zone file

so well and good uptill now

Thanks bathory sir and jayakumar for your help

I appreciate alot and HAPPY NEW YEAR