1 (edited by RafaelMass 2020-05-28 22:11:10)

Topic: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.0
- Deployed with iRedMail Easy or the downloadable installer? downloadable
- Linux/BSD distribution name and version:  Ubuntu 18.04 64
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MariaDB
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====


I need help because my email server is blocking messages from some vendors,.
mail.log

May 23 10:33:22 mx postfix/smtpd[28516]: connect from smtp08.novapontocom.com.br[177.126.185.182]
May 23 10:33:22 mx postfix/smtpd[28516]: Anonymous TLS connection established from smtp08.novapontocom.com.br[177.126.185.182]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
May 23 10:33:22 mx postfix/smtpd[28516]: NOQUEUE: reject: RCPT from smtp08.novapontocom.com.br[177.126.185.182]: 450 4.7.1 <SMTP-MX-4.dc.nova>: Helo command rejected: Host not found; from=<falecom@sac.extra.com.br> to=<user@mydomain.com.br> proto=ESMTP helo=<SMTP-MX-4.dc.nova>
May 23 10:33:22 mx postfix/smtpd[28516]: disconnect from smtp08.novapontocom.com.br[177.126.185.182] ehlo=2 starttls=1 mail=1 rcpt=0/1 data=0/1 rset=1 quit=1 commands=6/8

May 23 11:42:49 mx postfix/smtpd[3300]: connect from smtp07.novapontocom.com.br[177.126.185.96]
May 23 11:42:49 mx postfix/smtpd[3300]: Anonymous TLS connection established from smtp07.novapontocom.com.br[177.126.185.96]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
May 23 11:42:49 mx postfix/smtpd[3300]: NOQUEUE: reject: RCPT from smtp07.novapontocom.com.br[177.126.185.96]: 450 4.7.1 <SMTP-MX-3.dc.nova>: Helo command rejected: Host not found; from=<falecom@sac.extra.com.br> to=<user@mydomain.com.br> proto=ESMTP helo=<SMTP-MX-3.dc.nova>
May 23 11:42:49 mx postfix/smtpd[3300]: disconnect from smtp07.novapontocom.com.br[177.126.185.96] ehlo=2 starttls=1 mail=1 rcpt=0/1 data=0/1 rset=1 quit=1 commands=6/8

I tried the following commands:

python  /opt/iredapd/tools/spf_to_greylist_whitelists.py .novapontocom.com.br
python  /opt/iredapd/tools/spf_to_greylist_whitelists.py novapontocom.com.br
python  /opt/iredapd/tools/spf_to_greylist_whitelists.py sac.extra.com.br
python  /opt/iredapd/tools/spf_to_greylist_whitelists.py smtp08.novapontocom.com.br
python  /opt/iredapd/tools/wblist_admin.py --add --whitelist 177.126.185.182
python  /opt/iredapd/tools/spf_to_greylist_whitelists.py falecom@sac.extra.com.br
python  /opt/iredapd/tools/spf_to_greylist_whitelists.py sac.extra.com.br
python /opt/iRedAPD-3.3/tools/greylisting_admin.py --disable --to '@sac.extra.com.br'
python /opt/iredapd/tools/wblist_admin.py --add --whitelist @sac.extra.com.br @extra.com.br @.extra.com.br
python /opt/iRedAPD-3.3/tools/spf_to_greylist_whitelists.py novapontocom.com.br
python /opt/iRedAPD-3.3/tools/spf_to_greylist_whitelists.py extra.com.br
python /opt/iredapd/tools/wblist_admin.py --add --whitelist @.novapontocom.com.br

And added on end of /etc/postfix/helo_access.pcre:
/^.novapontocom\.com\.br$/ OK
/^sac\.extra\.com\.br$/ OK
/\.novapontocom\.com\.br$/ OK
/\.extra\.com\.br$/ OK


I restarted the services and the server, but it didn't work.
I have no idea what I could do, could anyone help?

----

Spider Email Archiver: On-Premises, lightweight email archiving software developed by iRedMail team. Supports Amazon S3 compatible storage and custom branding.

2

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

Which is the domain that you own and will be receiving email for?

3

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

Please show us output of command "postconf smtpd_helo_restrictions". It should be:

smtpd_helo_restrictions =
    permit_mynetworks
    permit_sasl_authenticated
    check_helo_access pcre:/etc/postfix/helo_access.pcre
    reject_non_fqdn_helo_hostname
    reject_unknown_helo_hostname

Then you can whitelists in /etc/postfix/helo_access.pcre will be applied before (Postfix) checking its reverse domain name ("Host not found").

4

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

Output from  postconf smtpd_helo_restrictions

smtpd_helo_restrictions = 
permit_mynetworks 
permit_sasl_authenticated 
check_helo_access pcre:/etc/postfix/helo_access.pcre 
reject_non_fqdn_helo_hostname 
reject_unknown_helo_hostname

5

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

Now are hapening with other  server mail.

May 26 09:15:02 mx postfix/smtpd[12607]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 09:15:02 mx postfix/smtpd[12607]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 09:30:01 mx postfix/smtpd[14313]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 09:30:01 mx postfix/smtpd[14313]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 09:31:15 mx amavis[11885]: (11885-12) Passed CLEAN {RelayedInternal}, ORIGINATING LOCAL [177.220.144.179]:7521 [177.220.144.179] <001@mydomain.com.br> -> <client02@friboi.com.br>, Queue-ID: 49WYGk4gSPz19b, Message-ID: <35d26e1f-2d46-2fde-35dc-e43143619e41@mydomain.com.br>, mail_id: J3JzvXGPUc4c, Hits: 1.143, size: 514398, queued_as: 49WYGq0mcZz4lq, dkim_new=dkim:mydomain.com.br, 4329 ms, Tests: [ALL_TRUSTED=-1,HTML_IMAGE_ONLY_12=1.629,HTML_MESSAGE=0.001,NORMAL_HTTP_TO_IP=0.001,NUMERIC_HTTP_ADDR=0.001,SUBJ_ALL_CAPS=0.5,T_REMOTE_IMAGE=0.01,URIBL_BLOCKED=0.001]
May 26 09:31:15 mx postfix/amavis/smtp[14357]: 49WYGk4gSPz19b: to=<client02@friboi.com.br>, relay=127.0.0.1[127.0.0.1]:10026, delay=4.5, delays=0.19/0/0.01/4.3, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 49WYGq0mcZz4lq)
May 26 09:31:15 mx amavis[12764]: (12764-04) Passed CLEAN {RelayedInternal}, ORIGINATING LOCAL [177.220.144.179]:7521 [177.220.144.179] <001@mydomain.com.br> -> <client04s@friboi.com.br>, Queue-ID: 49WYGk4gSPz19b, Message-ID: <35d26e1f-2d46-2fde-35dc-e43143619e41@mydomain.com.br>, mail_id: knHN67bVBVPh, Hits: 1.143, size: 514398, queued_as: 49WYGq1jjjz3xN, dkim_new=dkim:mydomain.com.br, 4460 ms, Tests: [ALL_TRUSTED=-1,HTML_IMAGE_ONLY_12=1.629,HTML_MESSAGE=0.001,NORMAL_HTTP_TO_IP=0.001,NUMERIC_HTTP_ADDR=0.001,SUBJ_ALL_CAPS=0.5,T_REMOTE_IMAGE=0.01,URIBL_BLOCKED=0.001]
May 26 09:31:15 mx postfix/amavis/smtp[14358]: 49WYGk4gSPz19b: to=<client04s@friboi.com.br>, relay=127.0.0.1[127.0.0.1]:10026, delay=4.7, delays=0.19/0/0.02/4.5, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 49WYGq1jjjz3xN)
May 26 09:31:15 mx amavis[12282]: (12282-09) Passed CLEAN {RelayedInternal}, ORIGINATING LOCAL [177.220.144.179]:7521 [177.220.144.179] <001@mydomain.com.br> -> <client05@friboi.com.br>, Queue-ID: 49WYGk4gSPz19b, Message-ID: <35d26e1f-2d46-2fde-35dc-e43143619e41@mydomain.com.br>, mail_id: ZHOJfqXPEfHF, Hits: 1.143, size: 514398, queued_as: 49WYGq368Vz3kM, dkim_new=dkim:mydomain.com.br, 4640 ms, Tests: [ALL_TRUSTED=-1,HTML_IMAGE_ONLY_12=1.629,HTML_MESSAGE=0.001,NORMAL_HTTP_TO_IP=0.001,NUMERIC_HTTP_ADDR=0.001,SUBJ_ALL_CAPS=0.5,T_REMOTE_IMAGE=0.01,URIBL_BLOCKED=0.001]
May 26 09:31:15 mx postfix/amavis/smtp[14360]: 49WYGk4gSPz19b: to=<client05@friboi.com.br>, relay=127.0.0.1[127.0.0.1]:10026, delay=4.9, delays=0.19/0/0.01/4.6, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as 49WYGq368Vz3kM)
May 26 09:31:17 mx postfix/smtp[14538]: 49WYGq1jjjz3xN: to=<client04s@friboi.com.br>, relay=burns.jbs.com.br[191.5.61.83]:25, delay=2.4, delays=0.05/0.03/0.6/1.7, dsn=2.0.0, status=sent (250 2.0.0 OK E4/08-07479-31C0DCE5)
May 26 09:31:17 mx postfix/smtp[14539]: 49WYGq368Vz3kM: to=<client05@friboi.com.br>, relay=burns.jbs.com.br[191.5.61.83]:25, delay=2.4, delays=0.03/0.03/0.45/1.9, dsn=2.0.0, status=sent (250 2.0.0 OK 25/08-07479-31C0DCE5)
May 26 09:31:21 mx postfix/smtp[14321]: 49WYGq0mcZz4lq: to=<client02@friboi.com.br>, relay=burns.jbs.com.br[191.5.61.83]:25, delay=6.1, delays=0.04/0.01/0.8/5.2, dsn=2.0.0, status=sent (250 2.0.0 OK 85/08-07479-41C0DCE5)
May 26 10:58:01 mx postfix/smtpd[23046]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 10:58:01 mx postfix/smtpd[23046]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 11:00:02 mx postfix/smtpd[21853]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 11:00:02 mx postfix/smtpd[21853]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 11:28:02 mx postfix/smtpd[25860]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 11:28:02 mx postfix/smtpd[25860]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 12:28:03 mx postfix/smtpd[31608]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 12:28:03 mx postfix/smtpd[31608]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 12:39:34 mx postfix/smtpd[31800]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client04s@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 12:39:36 mx postfix/smtpd[31800]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client04s@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:41:13 mx postfix/smtpd[2890]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client05@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:02 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<006@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:02 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<006@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:02 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<002@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:02 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<004@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:03 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:03 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<005@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>
May 26 13:42:03 mx postfix/smtpd[1509]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client03@friboi.com.br> to=<006@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>

6 (edited by RafaelMass 2020-05-27 03:35:22)

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

I commented the lines:
reject_non_fqdn_helo_hostname
reject_unknown_helo_hostname

But it's not safe to keep it that way.
log from a mail:

May 26 16:24:40 mx postfix/cleanup[7054]: 49WkRr3gt7z8NZ: message-id=<002101d63372$ca0630e0$5e1292a0$@martins@friboi.com.br>
May 26 16:24:40 mx postfix/qmgr[2706]: 49WkRr3gt7z8NZ: from=<client01@friboi.com.br>, size=4612, nrcpt=1 (queue active)
May 26 16:24:40 mx postfix/amavis/smtp[7059]: > 127.0.0.1[127.0.0.1]:10024: MAIL FROM:<client01@friboi.com.br> SIZE=4612 BODY=8BITMIME
May 26 16:24:40 mx postfix/amavis/smtp[7059]: < 127.0.0.1[127.0.0.1]:10024: 250 2.1.0 Sender <client01@friboi.com.br> OK
May 26 16:24:41 mx postfix/10025/smtpd[7064]: < ip6-localhost[127.0.0.1]: MAIL FROM:<client01@friboi.com.br> BODY=8BITMIME
May 26 16:24:41 mx postfix/10025/smtpd[7064]: dict_pcre_lookup: /etc/postfix/command_filter.pcre: MAIL FROM:<client01@friboi.com.br> BODY=8BITMIME
May 26 16:24:41 mx postfix/10025/smtpd[7064]: extract_addr: input: <client01@friboi.com.br>
May 26 16:24:41 mx postfix/10025/smtpd[7064]: smtpd_check_addr: addr=client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: send attr address = client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: input attribute value: client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: rewrite_clnt: local: client01@friboi.com.br -> client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: send attr address = client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: input attribute value: friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: input attribute value: client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: resolve_clnt: `' -> `client01@friboi.com.br' -> transp=`smtp' host=`friboi.com.br' rcpt=`client01@friboi.com.br' flags= class=default
May 26 16:24:41 mx postfix/10025/smtpd[7064]: ctable_locate: install entry key ?client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: extract_addr: in: <client01@friboi.com.br>, result: client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: rewrite_clnt: cached: local: client01@friboi.com.br -> client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: send attr sender = client01@friboi.com.br
May 26 16:24:41 mx postfix/10025/smtpd[7064]: resolve_clnt: `client01@friboi.com.br' -> `jeferson@mydomain.com.br' -> transp=`dovecot' host=`mydomain.com.br' rcpt=`jeferson@mydomain.com.br' flags= class=virtual
May 26 16:24:41 mx postfix/10025/smtpd[7064]: ctable_locate: install entry key client01@friboi.com.br?jeferson@mydomain.com.br
May 26 16:24:41 mx postfix/cleanup[7054]: 49WkRs52N1z8VT: message-id=<002101d63372$ca0630e0$5e1292a0$@martins@friboi.com.br>
May 26 16:24:41 mx postfix/qmgr[2706]: 49WkRs52N1z8VT: from=<client01@friboi.com.br>, size=5110, nrcpt=1 (queue active)
May 26 16:24:41 mx amavis[2475]: (02475-18) Passed CLEAN {RelayedInbound}, [191.5.61.83]:43158 [187.123.5.86] <client01@friboi.com.br> -> <jeferson@mydomain.com.br>, Queue-ID: 49WkRr3gt7z8NZ, Message-ID: <002101d63372$ca0630e0$5e1292a0$@martins@friboi.com.br>, mail_id: 4vjvqXnSIEyw, Hits: 1.004, size: 4612, queued_as: 49WkRs52N1z8VT, 1172 ms, Tests: [HTML_MESSAGE=0.001,MSGID_MULTIPLE_AT=1,RCVD_IN_MSPIKE_H3=0.001,RCVD_IN_MSPIKE_WL=0.001,SPF_HELO_NONE=0.001,SPF_PASS=-0.001,URIBL_BLOCKED=0.001]

7

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

is it safe and appropriate to leave these options disabled?
reject_non_fqdn_helo_hostname
reject_unknown_helo_hostname

8

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

- Do not remove rules in smtpd_helo_restrictions.
- You can whitelist them in /etc/postfix/helo_access.pcre. Make sure your pcre regular expression is correct.

For example:

May 26 09:15:02 mx postfix/smtpd[12607]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>

You should whitelist its HELO hostname "mtzsvmsmghml02.corporate.ad" like this:

/^mtzsvmsmghml02\.corporate\.ad$/ OK

If you want to whitelist all sub-domains, use this one:

/\.corporate\.ad$/ OK

Note, there's no '^' to match the beginning of the helo hostname.

9

Re: Helo command rejected: Host not found 450 4.7.1 - error [FIXED]

ZhangHuangbin wrote:

- Do not remove rules in smtpd_helo_restrictions.
- You can whitelist them in /etc/postfix/helo_access.pcre. Make sure your pcre regular expression is correct.

For example:

May 26 09:15:02 mx postfix/smtpd[12607]: NOQUEUE: reject: RCPT from burns.jbs.com.br[191.5.61.83]: 450 4.7.1 <mtzsvmsmghml02.corporate.ad>: Helo command rejected: Host not found; from=<client01@friboi.com.br> to=<001@mydomain.com.br> proto=ESMTP helo=<mtzsvmsmghml02.corporate.ad>

You should whitelist its HELO hostname "mtzsvmsmghml02.corporate.ad" like this:

/^mtzsvmsmghml02\.corporate\.ad$/ OK

If you want to whitelist all sub-domains, use this one:

/\.corporate\.ad$/ OK

Note, there's no '^' to match the beginning of the helo hostname.

It worked correctly. Thank you very much