Author Topic: Unable to send mail : Client Host rejected: Cannot find your hostname.  (Read 3809 times)

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All of a sudden I am getting Client Host rejected: Cannot find your hostname.

I have not changed anything on server, server is not blacklisted, my isp client ip is not black listed.

I have tried restarting SERVER ( this now is not clean, i have to start service manula, and then start most of the services when I get back into centos web panel).

Is there some sort of auto update thing tthat can 'screw up' installations?

belows is file
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
anvil_rate_time_unit = 3600s
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
delay_warning_time = 4
disable_vrfy_command = yes
html_directory = no
inet_interfaces = all
mail_owner = postfix
mailbox_size_limit = 2048000000
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
message_size_limit = 204800000
milter_default_action = accept
milter_protocol = 2
mydestination = $myhostname, localhost.$mydomain, localhost
mydomain = **MYDOMAIN**.com
myhostname = server.**MYDOMAIN**.com
mynetworks = $config_directory/mynetworks
newaliases_path = /usr/bin/newaliases.postfix
non_smtpd_milters = $smtpd_milters
queue_directory = /var/spool/postfix
recipient_bcc_maps = proxy:mysql:/etc/postfix/
recipient_delimiter = +
relay_domains = proxy:mysql:/etc/postfix/
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtp_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt
smtp_tls_session_cache_database = btree:$data_directory/smtp_tls_session_cache
smtp_use_tls = yes
smtpd_client_message_rate_limit = 500
smtpd_client_restrictions = reject_unknown_client
smtpd_data_restrictions = reject_unauth_pipelining
smtpd_helo_required = yes
smtpd_helo_restrictions =
smtpd_milters = inet:

smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination,reject_non_fqdn_sender,reject_non_fqdn_recipient,reject_unknown_recipient_domain,reject_rbl_client,reject_rbl_client,reject_rbl_client,check_policy_service unix:private/spfpolicy

smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_path = private/auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_restrictions =
smtpd_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt
smtpd_tls_cert_file = /etc/pki/tls/certs/server.**MYDOMAIN**.com.crt
smtpd_tls_key_file = /etc/pki/tls/private/server.**MYDOMAIN**.com.key
smtpd_tls_loglevel = 1
smtpd_tls_received_header = yes
smtpd_tls_security_level = may
smtpd_tls_session_cache_timeout = 3600s
smtpd_use_tls = yes
soft_bounce = yes
tls_random_source = dev:/dev/urandom
transport_maps = hash:/etc/postfix/transport
unknown_local_recipient_reject_code = 550
virtual_alias_maps = proxy:mysql:/etc/postfix/, regexp:/etc/postfix/virtual_regexp
virtual_gid_maps = static:12
virtual_mailbox_base = /var/vmail
virtual_mailbox_domains = proxy:mysql:/etc/postfix/
virtual_mailbox_maps = proxy:mysql:/etc/postfix/
virtual_minimum_uid = 101
virtual_transport = dovecot
virtual_uid_maps = static:101

Hope someone can help, been bashing head against wall. I have checked and double checked that my IP address is allowed through firewall etc.

Question. Would I need to create an entry in CWP dns on server to map my static client ip to belong to domain.

This is a simple config A single site, one user (me) allowed to update and send mail and this user (me) has a static ip; could it get any easier?


Re: Unable to send mail : Client Host rejected: Cannot find your hostname.
« Reply #1 on: August 16, 2016, 01:07:06 PM »
comment out this line in, will fix your problem

smtpd_client_restrictions = reject_unknown_client

comment out this line in, will fix your problem

smtpd_client_restrictions = reject_unknown_client

This was helpful. But My is not connecting via ssl

Hi, you have to set correct ca-bundle in postfix and dovecot configs
Code: [Select]
smtp_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt
smtpd_tls_CAfile = /etc/pki/tls/certs/ca-bundle.crt
Code: [Select]
ssl_ca =
You can ask me to solve any problem with your server for some money in pm  ;)
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