[CentOS] Re: sendmail not sending after reboot

Scott Silva ssilva at sgvwater.com
Mon Jun 9 17:15:14 UTC 2008


on 6-9-2008 6:03 AM Ray Leventhal spake the following:
> HI folks,
> 
> I've an up-to-date CentOS 5.x box on a small intranet (<20 users).
> 
> We did a reboot over the weekend and all appears well except that 
> clients on the LAN can no longer send email.  Just hangs/times out.  No 
> clear identifiers in the /var/log/maillog or /var/log/messages.
> 
> We're not setup for ESMTP as it's a closed network and I'm really hoping 
> for a kickstart as to where to look to get this going.
> 
> In case it helps, my sendmail.cf file is below.
> 
> Thanks in advance.
> -R
> 
> divert(-1)dnl
> dnl #
> 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 #
> dnl #     make -C /etc/mail
> dnl #
> include(`/usr/share/sendmail-cf/m4/cf.m4')dnl
> VERSIONID(`setup for linux')dnl
> OSTYPE(`linux')dnl
> dnl #
> dnl # Do not advertize sendmail version.
> dnl #
> dnl define(`confSMTP_LOGIN_MSG', `$j Sendmail; $b')dnl
> dnl #
> dnl # default logging level is 9, you might want to set it higher to
> dnl # debug the configuration
> dnl #
> dnl define(`confLOG_LEVEL', `9')dnl
> dnl #
> dnl # Uncomment and edit the following line if your outgoing mail needs to
> dnl # be sent out through an external mail server:
> dnl #
> dnl # define(`SMART_HOST', `smtp.your.provider')dnl
> dnl #
> define(`confDEF_USER_ID', ``8:12'')dnl
> dnl define(`confAUTO_REBUILD')dnl
> define(`confTO_CONNECT', `1m')dnl
> define(`confTRY_NULL_MX_LIST', `True')dnl
> define(`confDONT_PROBE_INTERFACES', `True')dnl
> define(`PROCMAIL_MAILER_PATH', `/usr/bin/procmail')dnl
> define(`ALIAS_FILE', `/etc/aliases')dnl
> define(`STATUS_FILE', `/var/log/mail/statistics')dnl
> define(`UUCP_MAILER_MAX', `2000000')dnl
> define(`confUSERDB_SPEC', `/etc/mail/userdb.db')dnl
> define(`confPRIVACY_FLAGS', `authwarnings,novrfy,noexpn,restrictqrun')dnl
> define(`confAUTH_OPTIONS', `A')dnl
> dnl #
> dnl # The following allows relaying if the user authenticates, and 
> disallows
> dnl # plaintext authentication (PLAIN/LOGIN) on non-TLS links
> dnl #
> dnl define(`confAUTH_OPTIONS', `A p')dnl
> 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.
> dnl #
> dnl TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
> dnl define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 
> LOGIN PLAIN')dnl
> 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 #
> 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 #
> 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 #
> dnl define(`confDONT_BLAME_SENDMAIL', `groupreadablekeyfile')dnl
> 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
> define(`confTO_IDENT', `0')dnl
> dnl FEATURE(delay_checks)dnl
> FEATURE(`no_default_msa', `dnl')dnl
> FEATURE(`smrsh', `/usr/sbin/smrsh')dnl
> FEATURE(`mailertable', `hash -o /etc/mail/mailertable.db')dnl
> FEATURE(`virtusertable', `hash -o /etc/mail/virtusertable.db')dnl
> FEATURE(redirect)dnl
> FEATURE(always_add_domain)dnl
> FEATURE(use_cw_file)dnl
> FEATURE(use_ct_file)dnl
> 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 #
> dnl define(`confMAX_DAEMON_CHILDREN', `20')dnl
> 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 #
> dnl define(`confCONNECTION_RATE_THROTTLE', `3')dnl
> dnl #
> dnl # The -t option will retry delivery if e.g. the user runs over his 
> quota.
> dnl #
> FEATURE(local_procmail, `', `procmail -t -Y -a $h -d $u')dnl
> FEATURE(`access_db', `hash -T<TMPF> -o /etc/mail/access.db')dnl
> FEATURE(`blacklist_recipients')dnl
> EXPOSED_USER(`root')dnl
> 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 #
> dnl define(`confLOCAL_MAILER', `cyrusv2')dnl
> dnl define(`CYRUSV2_MAILER_ARGS', `FILE /var/lib/imap/socket/lmtp')dnl
> 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,Addr=127.0.0.1, Name=MTA')dnl
> dnl #
> 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 #
> dnl DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
> 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 #
> dnl # For this to work your OpenSSL certificates must be configured.
> dnl #
> dnl DAEMON_OPTIONS(`Port=smtps, Name=TLSMTA, M=s')dnl
> 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 #
> dnl DAEMON_OPTIONS(`port=smtp,Addr=::1, Name=MTA-v6, Family=inet6')dnl
> dnl #
> dnl # enable both ipv6 and ipv4 in sendmail:
> dnl #
> dnl DAEMON_OPTIONS(`Name=MTA-v4, Family=inet, Name=MTA-v6, Family=inet6')
> dnl #
> 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 #
> FEATURE(`accept_unresolvable_domains')dnl
> dnl #
> dnl FEATURE(`relay_based_on_MX')dnl
> dnl #
> dnl # Also accept email sent to "localhost.localdomain" as local email.
> dnl #
> LOCAL_DOMAIN(`localhost.localdomain')dnl
> dnl #
> dnl # The following example makes mail from this host and any additional
> dnl # specified domains appear to be sent from mydomain.com
> dnl #
> dnl MASQUERADE_AS(`mydomain.com')dnl
> dnl #
> dnl # masquerade not just the headers, but the envelope as well
> dnl #
> dnl FEATURE(masquerade_envelope)dnl
> dnl #
> dnl # masquerade not just @mydomainalias.com, but @*.mydomainalias.com 
> as well
> dnl #
> dnl FEATURE(masquerade_entire_domain)dnl
> dnl #
> dnl MASQUERADE_DOMAIN(localhost)dnl
> dnl MASQUERADE_DOMAIN(localhost.localdomain)dnl
> dnl MASQUERADE_DOMAIN(mydomainalias.com)dnl
> dnl MASQUERADE_DOMAIN(mydomain.lan)dnl
> MAILER(smtp)dnl
> MAILER(procmail)dnl
> dnl MAILER(cyrusv2)dnl
> DAEMON_OPTIONS(`Name=smtp,Modifiers=b')
All your Daemon_options (`port... definitions are turned off (dnl).
You have effectively told sendmail to not listen to anybody.
At a minimum you need "DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')" 
turned on for local mail to move, or "DAEMON_OPTIONS(`Port=smtp, Name=MTA')" 
to listen to all interfaces.

-- 
MailScanner is like deodorant...
You hope everybody uses it, and
you notice quickly if they don't!!!!

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 258 bytes
Desc: OpenPGP digital signature
Url : http://lists.centos.org/pipermail/centos/attachments/20080609/41ae5305/signature.bin


More information about the CentOS mailing list