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I can't figure out how to be able to send mails using sendmail. I've a dovecot/sendmail installation and I can recieve mails OK but when I try to send mail I get the error message "Relaying denied. Proper authentication required."
Example from maillog:
Oct 2 18:10:08 localhost sendmail: l92GA4UC002196: ruleset=check_rcpt, arg1=<firstname.lastname@example.org>, relay=rl-nvt-kaxx.xxxxxx.xxx [000.000.000.000], reject= 550 5.7.1 <email@example.com>... Relaying denied. Proper authentication required .
Oct 2 18:10:08 localhost sendmail: l92GA4UC002196: from=<firstname.lastname@example.org>, size=0, class=0, nrcpts=0, proto=SMTP, daemon=MTA, relay=rl-nvt-kaxx.xxxxxx.xxx [000.000.000.000]
Here is my sendmail.mc:
dnl # This is the sendmail macro config file for m4. If you make changes to
dnl # /etc/mail/sendmail.mc, you will need to regenerate the
dnl # /etc/mail/sendmail.cf file by confirming that the sendmail-cf package is
dnl # installed and then performing a
dnl # make -C /etc/mail
VERSIONID(`setup for linux')dnl
dnl # Do not advertize sendmail version.
dnl define(`confSMTP_LOGIN_MSG', `$j Sendmail; $b')dnl
dnl # default logging level is 9, you might want to set it higher to
dnl # debug the configuration
dnl define(`confLOG_LEVEL', `9')dnl
dnl # Uncomment and edit the following line if your outgoing mail needs to
dnl # be sent out through an external mail server:
dnl # The following allows relaying if the user authenticates, and disallows
dnl # plaintext authentication (PLAIN/LOGIN) on non-TLS links
dnl define(`confAUTH_OPTIONS', `A p')dnl
dnl # PLAIN is the preferred plaintext authentication method and used by
dnl # Mozilla Mail and Evolution, though Outlook Express and other MUAs do
dnl # use LOGIN. Other mechanisms should be used if the connection is not
dnl # guaranteed secure.
dnl # Please remember that saslauthd needs to be running for AUTH.
TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
dnl # Rudimentary information on creating certificates for sendmail TLS:
dnl # cd /usr/share/ssl/certs; make sendmail.pem
dnl # Complete usage:
dnl # make -C /usr/share/ssl/certs usage
dnl define(`confCACERT_PATH', `/etc/pki/tls/certs')dnl
dnl define(`confCACERT', `/etc/pki/tls/certs/ca-bundle.crt')dnl
dnl define(`confSERVER_CERT', `/etc/pki/tls/certs/sendmail.pem')dnl
dnl define(`confSERVER_KEY', `/etc/pki/tls/certs/sendmail.pem')dnl
dnl # This allows sendmail to use a keyfile that is shared with OpenLDAP's
dnl # slapd, which requires the file to be readble by group ldap
dnl define(`confDONT_BLAME_SENDMAIL', `groupreadablekeyfile')dnl
dnl define(`confTO_QUEUEWARN', `4h')dnl
dnl define(`confTO_QUEUERETURN', `5d')dnl
dnl define(`confQUEUE_LA', `12')dnl
dnl define(`confREFUSE_LA', `18')dnl
FEATURE(`mailertable', `hash -o /etc/mail/mailertable.db')dnl
FEATURE(`virtusertable', `hash -o /etc/mail/virtusertable.db')dnl
dnl # The following limits the number of processes sendmail can fork to accept
dnl # incoming messages or process its message queues to 20.) sendmail refuses
dnl # to accept connections once it has reached its quota of child processes.
dnl define(`confMAX_DAEMON_CHILDREN', `20')dnl
dnl # Limits the number of new connections per second. This caps the overhead
dnl # incurred due to forking new sendmail processes. May be useful against
dnl # DoS attacks or barrages of spam. (As mentioned below, a per-IP address
dnl # limit would be useful but is not available as an option at this writing.)
dnl define(`confCONNECTION_RATE_THROTTLE', `3')dnl
dnl # The -t option will retry delivery if e.g. the user runs over his quota.
FEATURE(local_procmail, `', `procmail -t -Y -a $h -d $u')dnl
FEATURE(`access_db', `hash -T<TMPF> -o /etc/mail/access.db')dnl
dnl # For using Cyrus-IMAPd as POP3/IMAP server through LMTP delivery uncomment
dnl # the following 2 definitions and activate below in the MAILER section the
dnl # cyrusv2 mailer.
dnl define(`confLOCAL_MAILER', `cyrusv2')dnl
dnl define(`CYRUSV2_MAILER_ARGS', `FILE /var/lib/imap/socket/lmtp')dnl
dnl # The following causes sendmail to only listen on the IPv4 loopback address
dnl # 127.0.0.1 and not on any other network devices. Remove the loopback
dnl # address restriction to accept email from the internet or intranet.
dnl DAEMON_OPTIONS(`Port=smtp, Name=MTA')
dnl # The following causes sendmail to additionally listen to port 587 for
dnl # mail from MUAs that authenticate. Roaming users who can't reach their
dnl # preferred sendmail daemon due to port 25 being blocked or redirected find
dnl # this useful.
dnl DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
dnl # The following causes sendmail to additionally listen to port 465, but
dnl # starting immediately in TLS mode upon connecting. Port 25 or 587 followed
dnl # by STARTTLS is preferred, but roaming clients using Outlook Express can't
dnl # do STARTTLS on ports other than 25. Mozilla Mail can ONLY use STARTTLS
dnl # and doesn't support the deprecated smtps; Evolution <1.1.1 uses smtps
dnl # when SSL is enabled-- STARTTLS support is available in version 1.1.1.
dnl # For this to work your OpenSSL certificates must be configured.
dnl DAEMON_OPTIONS(`Port=smtps, Name=TLSMTA, M=s')dnl
dnl # The following causes sendmail to additionally listen on the IPv6 loopback
dnl # device. Remove the loopback address restriction listen to the network.
dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6')dnl
dnl # enable both ipv6 and ipv4 in sendmail:
dnl DAEMON_OPTIONS(`Name=MTA-v4, Family=inet, Name=MTA-v6, Family=inet6')
dnl # We strongly recommend not accepting unresolvable domains if you want to
dnl # protect yourself from spam. However, the laptop and users on computers
dnl # that do not have 24x7 DNS do need this.
dnl # Also accept email sent to "localhost.localdomain" as local email.
dnl # The following example makes mail from this host and any additional
dnl # specified domains appear to be sent from mydomain.com
dnl # masquerade not just the headers, but the envelope as well
dnl # masquerade not just @mydomainalias.com, but @*.mydomainalias.com as well
Here is my local-host-names:
Here is my relay-domains:
mydomain.com is actually my real domain, and the "xxxx.." parts of the IPs and mail addresses has just been changed for this thread. I really need help to solve this, I can't figure out why the server just gives me that error message regardless of what I do.. Please help!
How is your firewall configured? Can you just send over port 25 without client authentication? At one point a year ago, we went from the ability to send to our server to having to have client access. I built that into sendmail's config using a kind of shim. Of course, for all root/cron mail being sent from our Linux systems, my email id is the sender, but that's a small price to pay.
most likely the authentification mode configuration problem. Do you want plain auth mode? So that your SMTP will validate the user/password before sending email. You have to check the this option in your mail client software.