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SMTP by SendMail

Hi,

I am setting an email server using SendMail on RedHat Linux 9. I can receive and email from both internal and external network. However, I cannot send the email to other email accounts such as xxx@hotmail.com. After I check the /etc/log/mail/log.

The message is

.............. stat=Deferred: Connection refused...........

Anyone came across this problem and how to solve this?

Thanks.

Thomas

Can you send email to any other external domains such as yahoo.com? I've noticed a few other posts that mention Hotmail so I wonder if they're doing some agressive spam blocking.

# Common e-mail tools
sendmail - postfix - sends mail to local users (and internet when configured correctly)
fetchmail - gets mail from internet accounts (non-Hotmail type)
procmail - sorts and delivers into separate mailboxes
mutt - mail client that sucks less than all the others
Email the Linux Way
Suresh Ramasubramanian's email guide
The Linux Mail User HOWTO
The Linux Electronic Mail Administrator HOWTO
SquirrelMail web mail
Why use Hotmail when there is LinuxMail?
Gotmail, a utility to download mail from Hotmail type accounts

I found this file to configure sendmail on Suresh Ramasubramanian's email guide

Code:

divert(-1)

dnl This is the macro config file used to generate sendmail.cf

dnl file. If you modify this file you will have to regenerate 

dnl sendmail.cf by running this macro config through the m4

dnl preprocessor:

dnl

dnl        m4 /home/fancy/Documents/sendmail.mc > /etc/sendmail.cf <--Change to your path

dnl

dnl You will need to have the sendmail-cf RPM installed for this

dnl to work, if you use an rpm build of sendmail

dnl

dnl include(`../m4/cf.m4')

dnl

dnl If you compile sendmail from a tarball, use the include above.

dnl In this setup, you should create the file as cf/cf/config.mc 

dnl (in the sendmail source tree: eg. /usr/src/sendmail-8.11.6/cf/cf

dnl Now give the command "sh Build config.cf".  Now copy the file

dnl config.cf as /etc/mail/sendmail.cf (please backup first!)

dnl

dnl If you are using the RPM build of sendmail, use the 

dnl include statement given below instead

dnl

include(`/usr/share/sendmail-cf/m4/cf.m4')

define(`confDEF_USER_ID',``8:12'')

OSTYPE(`linux')

undefine(`UUCP_RELAY')

undefine(`BITNET_RELAY')

define(`confCF_VERSION',`dialup-1.3')

define(`SMART_HOST', `smtp.yourisp.com') <--Change this

define(`confAUTO_REBUILD')

define(`confTO_CONNECT', `1m')

define(`confTO_IDENT',0)

define(`confTRY_NULL_MX_LIST',true)

define(`confDONT_PROBE_INTERFACES',true)

define(`confCON_EXPENSIVE',true)

define(`confDELIVERY_MODE', `queued')

define(`PROCMAIL_MAILER_PATH',`/usr/bin/procmail')

define(`ALIAS_FILE',`/etc/mail/aliases')

MASQUERADE_AS(`yourisp.com') <--Change this

FEATURE(`masquerade_envelope')

FEATURE(`smrsh',`/usr/sbin/smrsh')

FEATURE(`mailertable',`hash -o /etc/mail/mailertable')

FEATURE(`virtusertable',`hash -o /etc/mail/virtusertable')

FEATURE(redirect)

FEATURE(always_add_domain)

FEATURE(use_cw_file)

FEATURE(`use_ct_file')

FEATURE(local_procmail)

MAILER(smtp)

MAILER(procmail)

FEATURE(`access_db')

FEATURE(`blacklist_recipients')

FEATURE(`accept_unresolvable_domains')

FEATURE(`accept_unqualified_senders')

dnl FEATURE(`relay_based_on_MX')

# Redhat links
RedHat Linux Manuals
Get your mp3 support here
Maximum RPM
rpmfind
Easier software management: apt4rpm - Red Carpet
RedHat 8.0 Tips & Tricks

# Redhat 7.3 down configuration commands
setup leads to several configuration tools

# Redhat 7.3 up configuration commands
Configure soundcard:
redhat-config-soundcard
Configure X server:
redhat-config-xfree86
Configure network:
redhat-config-network
Manage software:
redhat-config-packages

# Handling NTFS
New Technology FileSystem (NTFS) HOWTOs
Linux NTFS project

Some MTA's such as qmail use control files to secure against relaying, if the domain is not in the control file you can't send mail to it! There could be a control file such as this with sendmail, I am a qmail administrator so I'm just guessing!!

Are you on a dialup/DSL/cable subscriber connection to the InterNet and sending the e-mail directly from your machine to hotmail?

If so then your host will have a name such as

1-23-dialup-DSL-cable-something.yourISP.COM

When some sites see these types of names indicating an obvious temporary type host, they will refuse to accept the incoming mail.

The only way around this problem is to use your ISP mail machine as a smarthost relay.

Of course if HotMail or whoever has put a block on the entire domain of your ISP, then that is not going to work either.

Can you successfully email an AOL account?? AOL implements SPAM blocking including "ping -a x.x.x.x" (your IP address). If the resulting host name corresponding to that IP address is not on their list, your email will be refused (exactly what Corin is suggesting in prev post). Maybe Hotmail is doing the same thing. I've read that a work-around is to have your server relay all of your outgoing messages to whatever SMTP server is legitimately available from your ISP. You would be a legitimate user sending out email (from your ISP's SMTP server's point of view) ... then when it gets to AOL (or Hotmail, if they are doing the same thing) when they do "ping -a x.x.x.x" it will result coming from a sanctioned SMTP host and they should allow the email.