1. yum install logwatch
Package logwatch-7.3.6-52.el6.noarch already installed and latest version
Nothing to do

Any ideas?

2. I don't think it was because of fail2ban, because if it was then I should not log in with SSH, but I could.

1. Command has no effect. Then I checked /var/log/maillog and found following error:

May 26 16:46:44 knowsg amavis[967]: (00967-02) NOTICE: reconnecting in response to: err=2006, HY000, DBD::mysql::st execute failed: MySQL server has gone away at (eval 112) line 172.

MySQL server is very quiet and there should be less than 10 mails per day. I checked solution in this thread

http://www.iredmail.org/forum/topic2536 … ailed.html

But it is not working because I don't have /etc/amavis/conf.d/50-users.

I also tried to search through /etc/clamd.conf, still got no luck.

Please advise.

2. How to ensure that fail2ban is triggered by smtp/imap?

I applied changes to /etc/amavisd/amavisd.conf

$max_servers = 1;
$max_requests = 1;

before 1;

Then run

service amavisd restart
bash /etc/cron.daily/0logwatch

report still not seen in inbox of postmaster. Below is content from /var/log/maillog
May 26 19:06:49 knowsg postfix/pickup[5941]: 96C7169218FA: uid=0 from=<root>
May 26 19:06:49 knowsg postfix/cleanup[6446]: 96C7169218FA: message-id=<20150526110649.96C7169218FA@mail.knowsg.com>
May 26 19:06:49 knowsg postfix/qmgr[869]: 96C7169218FA: from=<root@mail.knowsg.com>, size=14022, nrcpt=1 (queue active)
May 26 19:06:53 knowsg postfix/smtpd[6454]: connect from mail.knowsg.com[127.0.0.1]
May 26 19:06:53 knowsg postfix/smtpd[6454]: 409206921865: client=mail.knowsg.com[127.0.0.1]
May 26 19:06:53 knowsg postfix/cleanup[6446]: 409206921865: message-id=<20150526110649.96C7169218FA@mail.knowsg.com>
May 26 19:06:53 knowsg postfix/qmgr[869]: 409206921865: from=<root@mail.knowsg.com>, size=14477, nrcpt=1 (queue active)
May 26 19:06:53 knowsg postfix/smtpd[6454]: disconnect from mail.knowsg.com[127.0.0.1]
May 26 19:06:53 knowsg amavis[6071]: (06071-01) Passed CLEAN {RelayedInternal}, MYUSERS <root@mail.knowsg.com> -> <root@mail.knowsg.com>, Message-ID: <20150526110649.96C7169218FA@mail.knowsg.com>, mail_id: HPcBrRtdyHMM, Hits: -0.001, size: 14011, queued_as: 409206921865, 3623 ms
May 26 19:06:53 knowsg postfix/smtp[6458]: 409206921865: to=<root@mail.knowsg.com>, relay=none, delay=0.03, delays=0.01/0.02/0/0, dsn=5.4.6, status=bounced (mail for mail.knowsg.com loops back to myself)
May 26 19:06:53 knowsg postfix/cleanup[6446]: 4FE9B69219C1: message-id=<20150526110653.4FE9B69219C1@mail.knowsg.com>
May 26 19:06:53 knowsg postfix/smtp[6450]: 96C7169218FA: to=<root@mail.knowsg.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=12, delays=8.1/0.03/0.01/3.6, 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 409206921865)
May 26 19:06:53 knowsg postfix/qmgr[869]: 4FE9B69219C1: from=<>, size=16373, nrcpt=1 (queue active)
May 26 19:06:53 knowsg postfix/bounce[6459]: 409206921865: sender non-delivery notification: 4FE9B69219C1
May 26 19:06:53 knowsg postfix/qmgr[869]: 96C7169218FA: removed
May 26 19:06:53 knowsg postfix/qmgr[869]: 409206921865: removed
May 26 19:06:53 knowsg postfix/smtp[6458]: 4FE9B69219C1: to=<root@mail.knowsg.com>, relay=none, delay=0.01, delays=0/0/0/0, dsn=5.4.6, status=bounced (mail for mail.knowsg.com loops back to myself)
May 26 19:06:53 knowsg postfix/qmgr[869]: 4FE9B69219C1: removed

root: postmaster@KnowSG.com

alias_database = hash:/etc/postfix/aliases
alias_maps = hash:/etc/postfix/aliases
allow_min_user = no
allow_percent_hack = no
biff = no
bounce_queue_lifetime = 4h
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
content_filter = smtp-amavis:[127.0.0.1]:10024
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
debugger_command = PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin ddd $daemon_directory/$process_name $process_id & sleep 5
delay_warning_time = 0h
disable_vrfy_command = yes
dovecot_destination_recipient_limit = 1
enable_original_recipient = no
home_mailbox = Maildir/
html_directory = no
inet_interfaces = all
inet_protocols = ipv4
lmtp_tls_mandatory_protocols = !SSLv2 !SSLv3
lmtp_tls_protocols = !SSLv2 !SSLv3
mail_owner = postfix
mailbox_command = /usr/libexec/dovecot/deliver
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
maximal_backoff_time = 4000s
maximal_queue_lifetime = 4h
message_size_limit = 15728640
minimal_backoff_time = 300s
mydestination = localhost, localhost.localdomain
mydomain = mail.knowsg.com
myhostname = mail.knowsg.com
mynetworks = 127.0.0.1
mynetworks_style = host
myorigin = mail.knowsg.com
newaliases_path = /usr/bin/newaliases.postfix
proxy_read_maps = $canonical_maps $lmtp_generic_maps $local_recipient_maps $mydestination $mynetworks $recipient_bcc_maps $recipient_canonical_maps $relay_domains $relay_recipient_maps $relocated_maps $sender_bcc_maps $sender_canonical_maps $smtp_generic_maps $smtpd_sender_login_maps $transport_maps $virtual_alias_domains $virtual_alias_maps $virtual_mailbox_domains $virtual_mailbox_maps $smtpd_sender_restrictions
queue_directory = /var/spool/postfix
queue_run_delay = 300s
readme_directory = /usr/share/doc/postfix-2.11.0/README_FILES
recipient_bcc_maps = proxy:mysql:/etc/postfix/mysql/recipient_bcc_maps_user.cf, proxy:mysql:/etc/postfix/mysql/recipient_bcc_maps_domain.cf
recipient_delimiter = +
relay_domains = $mydestination, proxy:mysql:/etc/postfix/mysql/relay_domains.cf
sample_directory = /usr/share/doc/postfix-2.11.0/samples
sender_bcc_maps = proxy:mysql:/etc/postfix/mysql/sender_bcc_maps_user.cf, proxy:mysql:/etc/postfix/mysql/sender_bcc_maps_domain.cf
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtp-amavis_destination_recipient_limit = 1
smtp_data_init_timeout = 240s
smtp_data_xfer_timeout = 600s
smtp_tls_CAfile = $smtpd_tls_CAfile
smtp_tls_loglevel = 0
smtp_tls_mandatory_protocols = !SSLv2 !SSLv3
smtp_tls_note_starttls_offer = yes
smtp_tls_protocols = !SSLv2 !SSLv3
smtp_tls_security_level = may
smtpd_data_restrictions = reject_unauth_pipelining
smtpd_end_of_data_restrictions = check_policy_service inet:127.0.0.1:7777, check_policy_service inet:127.0.0.1:10031,
smtpd_helo_required = yes
smtpd_helo_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_helo_hostname, reject_invalid_helo_hostname, check_helo_access pcre:/etc/postfix/helo_access.pcre
smtpd_recipient_restrictions = reject_unknown_recipient_domain, reject_non_fqdn_recipient, reject_unlisted_recipient, check_policy_service inet:127.0.0.1:7777, check_policy_service inet:127.0.0.1:10031, permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
smtpd_reject_unlisted_recipient = yes
smtpd_reject_unlisted_sender = yes
smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain =
smtpd_sasl_path = private/dovecot-auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_login_maps = proxy:mysql:/etc/postfix/mysql/sender_login_maps.cf
smtpd_sender_restrictions = reject_unknown_sender_domain, reject_non_fqdn_sender, reject_unlisted_sender, permit_mynetworks, reject_sender_login_mismatch, permit_sasl_authenticated
smtpd_tls_CAfile = /etc/pki/tls/certs/unified.crt
smtpd_tls_auth_only = yes
smtpd_tls_cert_file = /etc/pki/tls/certs/ssl.crt
smtpd_tls_key_file = /etc/pki/tls/private/ssl.key
smtpd_tls_loglevel = 0
smtpd_tls_mandatory_protocols = !SSLv2 !SSLv3
smtpd_tls_protocols = !SSLv2 !SSLv3
smtpd_tls_security_level = may
smtpd_use_tls = yes
swap_bangpath = no
tls_random_source = dev:/dev/urandom
transport_maps = proxy:mysql:/etc/postfix/mysql/transport_maps_user.cf, proxy:mysql:/etc/postfix/mysql/transport_maps_domain.cf
unknown_local_recipient_reject_code = 550
virtual_alias_domains =
virtual_alias_maps = proxy:mysql:/etc/postfix/mysql/virtual_alias_maps.cf, proxy:mysql:/etc/postfix/mysql/domain_alias_maps.cf, proxy:mysql:/etc/postfix/mysql/catchall_maps.cf, proxy:mysql:/etc/postfix/mysql/domain_alias_catchall_maps.cf
virtual_gid_maps = static:2000
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql/virtual_mailbox_domains.cf
virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql/virtual_mailbox_maps.cf
virtual_minimum_uid = 2000
virtual_transport = dovecot
virtual_uid_maps = static:2000

Hello Any response please?