I have centos 4.8 i686. It has stock sendmail. see file below.

I am getting reports that it is an open relay. I have searched all around and it seems like it should be closed. I have dnl for accept_unresolvable_domains.

What can I do to close my sendmail. Thanks,

Jerry

My sendmail.mc is as follows: --------------------------------- 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 Red Hat Linux')dnl OSTYPE(`linux')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 # 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',`/usr/share/ssl/certs') dnl define(`confCACERT',`/usr/share/ssl/certs/ca-bundle.crt') dnl define(`confSERVER_CERT',`/usr/share/ssl/certs/sendmail.pem') dnl define(`confSERVER_KEY',`/usr/share/ssl/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 # 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 12.) sendmail refuses dnl # to accept connections once it has reached its quota of child processes. dnl # dnl define(`confMAX_DAEMON_CHILDREN', 12)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 $u')dnl FEATURE(`access_db',`hash -T<TMPF> -o /etc/mail/access.db')dnl FEATURE(`blacklist_recipients')dnl dnl # dnl # dnsbl - DNS based Blackhole List/Black List/Rejection list dnl # See http://www.sendmail.org/m4/features.html#dnsbl dnl # FEATURE(`dnsbl', `bl.spamcop.net', `"Spam blocked see: http://spamcop.net/bl.shtml?%22$&%7Bclient_addr%7D%27)dnl FEATURE(`dnsbl', `cbl.abuseat.org', `"Spam blocked see: http://cbl.abuseat.org/lookup.cgi?ip=%22$&%7Bclient_addr%7D%27)dnl FEATURE(`dnsbl', `sbl.spamhaus.org', `"Spam blocked see: http://spamhaus.org/query/bl?ip=%22$&%7Bclient_addr%7D%27)dnl FEATURE(`dnsbl', `list.dsbl.org', `"Spam blocked see: http://dsbl.org/listing?%22$&%7Bclient_addr%7D%27)dnl dnl # EXPOSED_USER(`root')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 # 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 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 # 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(`messagenetsystems.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.localdomain)dnl dnl MASQUERADE_DOMAIN(mydomainalias.com)dnl dnl MASQUERADE_DOMAIN(messagenetsystems.com)dnl MAILER(smtp)dnl MAILER(procmail)dnl dnl FEATURE(`accept_unresolvable_domains')