Our email server has been running for a couple of years, and I’ve not really noticed any problems with the mail transport before. That’s not to say there haven’t been problems, but it generally just delivers mail, and there have only been a limited number of occasions when a user has complained that email has taken a long while to arrive at its destination. However, I had a couple of complaints this week that some emails have taken ages to arrive. One was sent during the day, and it didn’t arrive until midnight. I don’t know much about PostFix, and have had to look up the various commands. I’ve run ‘mailq’ and that is currently listing around 21 messages (it was about 53 an hour ago). Many of the messages listed in the queue have the following format
345484E370 12255 Wed Jul 19 08:14:20 kathleen@mydomain.co.uk
(conversation with smtp.saqnet.co.uk[195.2.156.65] timed out while sending MAIL
FROM)
office@destinationdomain.co.uk
This message was sent at 8:14, and it’s now just after mid-day. However, I’ve been able to send a test message to a webmail account, and that was delivered fairly soon after sending.
I’ve looked at the /var/log/mail log file, and that has entries saying
ms1 imapd[20571]: idle for too long, closing connection
Our ISP says there are no problems with their mail server. We are sending all mail via their relay server. I’ve listed the output of ‘postconf’ below. Is it something to do with the one of the smtp timeout parameters? I notice that some are in the region of 5minutes (300s), and I read somewhere that if messages can’t be delivered then Postfix increases the time period between each retry.
When I checked the files in the /var/spool/postfix directory, there was a total of 20MB. Yesterday when I checked it, it was 80MB in size, so we’re probably quite heavy users, with a fair number of message attachments.
I’d appreciate with determining if we have a problem, and if so, how to tune the system to fix it.
Postconf output…
2bounce_notice_recipient = $error_notice_recipient
access_map_reject_code = 554
alias_database = hash:/etc/postfix/aliases
alias_maps = hash:/etc/postfix/aliases
allow_mail_to_commands = alias,forward
allow_mail_to_files = alias,forward
allow_min_user = no
allow_percent_hack = yes
allow_untrusted_routing = no
alternate_config_directories =
always_bcc =
append_at_myorigin = yes
append_dot_mydomain = yes
best_mx_transport =
biff = yes
body_checks =
bounce_notice_recipient = $error_notice_recipient
bounce_size_limit = 50000
broken_sasl_auth_clients = no
canonical_maps =
command_directory = /usr/sbin
command_expansion_filter = 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
command_time_limit = 1000s
config_directory = /etc/postfix
content_filter =
daemon_directory = /usr/libexec/postfix
daemon_timeout = 18000s
debug_peer_level = 2
debug_peer_list =
default_database_type = hash
default_delivery_slot_cost = 5
default_delivery_slot_discount = 50
default_delivery_slot_loan = 3
default_destination_concurrency_limit = 10
default_destination_recipient_limit = 50
default_extra_recipient_limit = 1000
default_minimum_delivery_slots = 3
default_privs = nobody
default_process_limit = 50
default_recipient_limit = 10000
default_transport = smtp
default_verp_delimiters = +=
defer_transports =
delay_notice_recipient = $error_notice_recipient
delay_warning_time = 0h
deliver_lock_attempts = 20
deliver_lock_delay = 1s
disable_dns_lookups = no
disable_verp_bounces = no
disable_vrfy_command = no
domain_in_alias = yes
dont_remove = 0
double_bounce_sender = double-bounce
duplicate_filter_limit = 1000
empty_address_recipient = MAILER-DAEMON
error_notice_recipient = postmaster@scoms1.macandmac.co.uk
expand_owner_alias = no
export_environment = TZ
extract_recipient_limit = 10240
fallback_relay =
fallback_transport = cyrus
fast_flush_domains = $relay_domains
fast_flush_purge_time = 7d
fast_flush_refresh_time = 12h
fault_injection_code = 0
fork_attempts = 5
fork_delay = 1s
forward_expansion_filter = 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
forward_path = $home/.forward${recipient_delimiter}${extension},$home/.forward
hash_queue_depth = 2
hash_queue_names = incoming,active,deferred,bounce,defer,flush
header_checks =
header_size_limit = 102400
home_mailbox =
hopcount_limit = 50
ignore_mx_lookup_error = no
import_environment = MAIL_CONFIG MAIL_DEBUG MAIL_LOGTAG TZ XAUTHORITY DISPLAY
in_flow_delay = 1s
inet_interfaces = all
initial_destination_concurrency = 5
invalid_hostname_reject_code = 501
ipc_idle = 100s
ipc_timeout = 3600s
line_length_limit = 2048
lmtp_cache_connection = yes
lmtp_connect_timeout = 0s
lmtp_data_done_timeout = 600s
lmtp_data_init_timeout = 120s
lmtp_data_xfer_timeout = 180s
lmtp_lhlo_timeout = 300s
lmtp_mail_timeout = 300s
lmtp_quit_timeout = 300s
lmtp_rcpt_timeout = 300s
lmtp_rset_timeout = 300s
lmtp_sasl_auth_enable = no
lmtp_sasl_password_maps =
lmtp_sasl_security_options = noplaintext, noanonymous
lmtp_skip_quit_response = no
lmtp_tcp_port = 24
local_command_shell =
local_destination_concurrency_limit = 2
local_destination_recipient_limit = 1
local_recipient_maps = $virtual_maps
local_transport = local
luser_relay =
mail_name = Postfix
mail_owner = postfix
mail_release_date = 20020201
mail_spool_directory = /var/mail
mail_version = 1.1.3
mailbox_command =
mailbox_command_maps =
mailbox_delivery_lock = flock, dotlock
mailbox_size_limit = 30000000
mailbox_transport =
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man/en
maps_rbl_domains =
maps_rbl_reject_code = 554
masquerade_classes = envelope_sender, header_sender, header_recipient
masquerade_domains =
masquerade_exceptions =
max_idle = 100s
max_use = 100
maximal_backoff_time = 4000s
maximal_queue_lifetime = 5d
message_size_limit = 30000000
minimal_backoff_time = 1000s
mydestination = $myhostname, localhost.$mydomain, macandmac.co.uk
mydomain = macandmac.co.uk
myhostname = scoms1.macandmac.co.uk
mynetworks = 127.0.0.0/8 192.0.0.0/24
mynetworks_style = subnet
myorigin = $myhostname
newaliases_path = /usr/bin/newaliases
non_fqdn_reject_code = 504
notify_classes = resource,software
owner_request_special = yes
parent_domain_matches_subdomains = debug_peer_list,fast_flush_domains,mynetworks,permit_mx_backup_networks,qmqpd_authorized_clients,relay_domains,smtpd_access_maps
permit_mx_backup_networks =
prepend_delivered_header = command, file, forward
process_id_directory = pid
program_directory = /usr/libexec/postfix
propagate_unmatched_extensions = canonical, virtual
qmgr_fudge_factor = 100
qmgr_message_active_limit = 10000
qmgr_message_recipient_limit = 10000
qmgr_message_recipient_minimum = 10
qmgr_site_hog_factor = 100
qmqpd_authorized_clients =
qmqpd_error_delay = 5s
qmqpd_timeout = 300s
queue_directory = /var/spool/postfix
queue_minfree = 0
queue_run_delay = 1000s
readme_directory = /etc/postfix/README
recipient_canonical_maps =
recipient_delimiter =
reject_code = 554
relay_clientcerts =
relay_domains = $mydestination
relay_domains_reject_code = 554
relayhost = smtp.saqnet.co.uk
relocated_maps =
require_home_directory = no
sample_directory = /etc/postfix/sample
sender_canonical_maps =
sendmail_path = /usr/lib/sendmail
service_throttle_time = 60s
setgid_group = postdrop
smtp_always_send_ehlo = yes
smtp_bind_address =
smtp_break_lines = yes
smtp_connect_timeout = 0s
smtp_data_done_timeout = 600s
smtp_data_init_timeout = 120s
smtp_data_xfer_timeout = 180s
smtp_destination_concurrency_limit = $default_destination_concurrency_limit
smtp_destination_recipient_limit = $default_destination_recipient_limit
smtp_enforce_tls = no
smtp_helo_timeout = 300s
smtp_mail_timeout = 300s
smtp_never_send_ehlo = no
smtp_pix_workaround_delay_time = 10s
smtp_pix_workaround_threshold_time = 500s
smtp_quit_timeout = 300s
smtp_randomize_addresses = yes
smtp_rcpt_timeout = 300s
smtp_sasl_auth_enable = no
smtp_sasl_password_maps =
smtp_sasl_security_options = noplaintext, noanonymous
smtp_skip_4xx_greeting = yes
smtp_skip_5xx_greeting = yes
smtp_skip_quit_response = yes
smtp_starttls_timeout = 300s
smtp_tls_CAfile =
smtp_tls_CApath =
smtp_tls_cert_file =
smtp_tls_cipherlist =
smtp_tls_dcert_file =
smtp_tls_dkey_file = $smtp_tls_dcert_file
smtp_tls_enforce_peername = yes
smtp_tls_key_file = $smtp_tls_cert_file
smtp_tls_loglevel = 0
smtp_tls_note_starttls_offer = no
smtp_tls_per_site =
smtp_tls_session_cache_database =
smtp_tls_session_cache_timeout = 3600s
smtp_use_tls = no
smtpd_banner = $myhostname ESMTP $mail_name
smtpd_client_restrictions =
smtpd_delay_reject = yes
smtpd_enforce_tls = no
smtpd_error_sleep_time = 5s
smtpd_etrn_restrictions =
smtpd_hard_error_limit = 100
smtpd_helo_required = no
smtpd_helo_restrictions =
smtpd_history_flush_threshold = 100
smtpd_junk_command_limit = 100
smtpd_noop_commands =
smtpd_null_access_lookup_key = <>
smtpd_recipient_limit = 1000
smtpd_recipient_restrictions = check_client_access btree:/etc/postfix/dracd, permit_mynetworks, check_relay_domains
smtpd_restriction_classes =
smtpd_sasl_auth_enable = no
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_security_options = noanonymous
smtpd_sender_login_maps =
smtpd_sender_restrictions =
smtpd_soft_error_limit = 10
smtpd_timeout = 300s
smtpd_tls_CAfile = /etc/ssl/postfix-cert.pem
smtpd_tls_CApath =
smtpd_tls_ask_ccert = no
smtpd_tls_auth_only = no
smtpd_tls_ccert_verifydepth = 5
smtpd_tls_cert_file = /etc/ssl/postfix-cert.pem
smtpd_tls_cipherlist =
smtpd_tls_dcert_file =
smtpd_tls_dh1024_param_file =
smtpd_tls_dh512_param_file =
smtpd_tls_dkey_file = $smtpd_tls_dcert_file
smtpd_tls_key_file = /etc/ssl/postfix-key.pem
smtpd_tls_loglevel = 0
smtpd_tls_received_header = no
smtpd_tls_req_ccert = no
smtpd_tls_session_cache_database =
smtpd_tls_session_cache_timeout = 3600s
smtpd_tls_wrappermode = no
smtpd_use_tls = yes
soft_bounce = no
stale_lock_time = 500s
strict_rfc821_envelopes = no
sun_mailtool_compatibility = no
swap_bangpath = yes
syslog_facility = mail
syslog_name = postfix
tls_daemon_random_bytes = 32
tls_daemon_random_source =
tls_random_bytes = 32
tls_random_exchange_name = ${config_directory}/prng_exch
tls_random_prng_update_period = 60s
tls_random_reseed_period = 3600s
tls_random_source =
transport_maps = hash:/etc/postfix/transport
transport_retry_time = 60s
trigger_timeout = 10s
undisclosed_recipients_header = To: undisclosed-recipients:;
unknown_address_reject_code = 450
unknown_client_reject_code = 450
unknown_hostname_reject_code = 450
verp_delimiter_filter = -=+
virtual_gid_maps =
virtual_mailbox_base =
virtual_mailbox_limit = 51200000
virtual_mailbox_lock = fcntl
virtual_mailbox_maps =
virtual_maps = ldap:ldapsource
virtual_minimum_uid = 100
virtual_uid_maps =
345484E370 12255 Wed Jul 19 08:14:20 kathleen@mydomain.co.uk
(conversation with smtp.saqnet.co.uk[195.2.156.65] timed out while sending MAIL
FROM)
office@destinationdomain.co.uk
This message was sent at 8:14, and it’s now just after mid-day. However, I’ve been able to send a test message to a webmail account, and that was delivered fairly soon after sending.
I’ve looked at the /var/log/mail log file, and that has entries saying
ms1 imapd[20571]: idle for too long, closing connection
Our ISP says there are no problems with their mail server. We are sending all mail via their relay server. I’ve listed the output of ‘postconf’ below. Is it something to do with the one of the smtp timeout parameters? I notice that some are in the region of 5minutes (300s), and I read somewhere that if messages can’t be delivered then Postfix increases the time period between each retry.
When I checked the files in the /var/spool/postfix directory, there was a total of 20MB. Yesterday when I checked it, it was 80MB in size, so we’re probably quite heavy users, with a fair number of message attachments.
I’d appreciate with determining if we have a problem, and if so, how to tune the system to fix it.
Postconf output…
2bounce_notice_recipient = $error_notice_recipient
access_map_reject_code = 554
alias_database = hash:/etc/postfix/aliases
alias_maps = hash:/etc/postfix/aliases
allow_mail_to_commands = alias,forward
allow_mail_to_files = alias,forward
allow_min_user = no
allow_percent_hack = yes
allow_untrusted_routing = no
alternate_config_directories =
always_bcc =
append_at_myorigin = yes
append_dot_mydomain = yes
best_mx_transport =
biff = yes
body_checks =
bounce_notice_recipient = $error_notice_recipient
bounce_size_limit = 50000
broken_sasl_auth_clients = no
canonical_maps =
command_directory = /usr/sbin
command_expansion_filter = 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
command_time_limit = 1000s
config_directory = /etc/postfix
content_filter =
daemon_directory = /usr/libexec/postfix
daemon_timeout = 18000s
debug_peer_level = 2
debug_peer_list =
default_database_type = hash
default_delivery_slot_cost = 5
default_delivery_slot_discount = 50
default_delivery_slot_loan = 3
default_destination_concurrency_limit = 10
default_destination_recipient_limit = 50
default_extra_recipient_limit = 1000
default_minimum_delivery_slots = 3
default_privs = nobody
default_process_limit = 50
default_recipient_limit = 10000
default_transport = smtp
default_verp_delimiters = +=
defer_transports =
delay_notice_recipient = $error_notice_recipient
delay_warning_time = 0h
deliver_lock_attempts = 20
deliver_lock_delay = 1s
disable_dns_lookups = no
disable_verp_bounces = no
disable_vrfy_command = no
domain_in_alias = yes
dont_remove = 0
double_bounce_sender = double-bounce
duplicate_filter_limit = 1000
empty_address_recipient = MAILER-DAEMON
error_notice_recipient = postmaster@scoms1.macandmac.co.uk
expand_owner_alias = no
export_environment = TZ
extract_recipient_limit = 10240
fallback_relay =
fallback_transport = cyrus
fast_flush_domains = $relay_domains
fast_flush_purge_time = 7d
fast_flush_refresh_time = 12h
fault_injection_code = 0
fork_attempts = 5
fork_delay = 1s
forward_expansion_filter = 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
forward_path = $home/.forward${recipient_delimiter}${extension},$home/.forward
hash_queue_depth = 2
hash_queue_names = incoming,active,deferred,bounce,defer,flush
header_checks =
header_size_limit = 102400
home_mailbox =
hopcount_limit = 50
ignore_mx_lookup_error = no
import_environment = MAIL_CONFIG MAIL_DEBUG MAIL_LOGTAG TZ XAUTHORITY DISPLAY
in_flow_delay = 1s
inet_interfaces = all
initial_destination_concurrency = 5
invalid_hostname_reject_code = 501
ipc_idle = 100s
ipc_timeout = 3600s
line_length_limit = 2048
lmtp_cache_connection = yes
lmtp_connect_timeout = 0s
lmtp_data_done_timeout = 600s
lmtp_data_init_timeout = 120s
lmtp_data_xfer_timeout = 180s
lmtp_lhlo_timeout = 300s
lmtp_mail_timeout = 300s
lmtp_quit_timeout = 300s
lmtp_rcpt_timeout = 300s
lmtp_rset_timeout = 300s
lmtp_sasl_auth_enable = no
lmtp_sasl_password_maps =
lmtp_sasl_security_options = noplaintext, noanonymous
lmtp_skip_quit_response = no
lmtp_tcp_port = 24
local_command_shell =
local_destination_concurrency_limit = 2
local_destination_recipient_limit = 1
local_recipient_maps = $virtual_maps
local_transport = local
luser_relay =
mail_name = Postfix
mail_owner = postfix
mail_release_date = 20020201
mail_spool_directory = /var/mail
mail_version = 1.1.3
mailbox_command =
mailbox_command_maps =
mailbox_delivery_lock = flock, dotlock
mailbox_size_limit = 30000000
mailbox_transport =
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man/en
maps_rbl_domains =
maps_rbl_reject_code = 554
masquerade_classes = envelope_sender, header_sender, header_recipient
masquerade_domains =
masquerade_exceptions =
max_idle = 100s
max_use = 100
maximal_backoff_time = 4000s
maximal_queue_lifetime = 5d
message_size_limit = 30000000
minimal_backoff_time = 1000s
mydestination = $myhostname, localhost.$mydomain, macandmac.co.uk
mydomain = macandmac.co.uk
myhostname = scoms1.macandmac.co.uk
mynetworks = 127.0.0.0/8 192.0.0.0/24
mynetworks_style = subnet
myorigin = $myhostname
newaliases_path = /usr/bin/newaliases
non_fqdn_reject_code = 504
notify_classes = resource,software
owner_request_special = yes
parent_domain_matches_subdomains = debug_peer_list,fast_flush_domains,mynetworks,permit_mx_backup_networks,qmqpd_authorized_clients,relay_domains,smtpd_access_maps
permit_mx_backup_networks =
prepend_delivered_header = command, file, forward
process_id_directory = pid
program_directory = /usr/libexec/postfix
propagate_unmatched_extensions = canonical, virtual
qmgr_fudge_factor = 100
qmgr_message_active_limit = 10000
qmgr_message_recipient_limit = 10000
qmgr_message_recipient_minimum = 10
qmgr_site_hog_factor = 100
qmqpd_authorized_clients =
qmqpd_error_delay = 5s
qmqpd_timeout = 300s
queue_directory = /var/spool/postfix
queue_minfree = 0
queue_run_delay = 1000s
readme_directory = /etc/postfix/README
recipient_canonical_maps =
recipient_delimiter =
reject_code = 554
relay_clientcerts =
relay_domains = $mydestination
relay_domains_reject_code = 554
relayhost = smtp.saqnet.co.uk
relocated_maps =
require_home_directory = no
sample_directory = /etc/postfix/sample
sender_canonical_maps =
sendmail_path = /usr/lib/sendmail
service_throttle_time = 60s
setgid_group = postdrop
smtp_always_send_ehlo = yes
smtp_bind_address =
smtp_break_lines = yes
smtp_connect_timeout = 0s
smtp_data_done_timeout = 600s
smtp_data_init_timeout = 120s
smtp_data_xfer_timeout = 180s
smtp_destination_concurrency_limit = $default_destination_concurrency_limit
smtp_destination_recipient_limit = $default_destination_recipient_limit
smtp_enforce_tls = no
smtp_helo_timeout = 300s
smtp_mail_timeout = 300s
smtp_never_send_ehlo = no
smtp_pix_workaround_delay_time = 10s
smtp_pix_workaround_threshold_time = 500s
smtp_quit_timeout = 300s
smtp_randomize_addresses = yes
smtp_rcpt_timeout = 300s
smtp_sasl_auth_enable = no
smtp_sasl_password_maps =
smtp_sasl_security_options = noplaintext, noanonymous
smtp_skip_4xx_greeting = yes
smtp_skip_5xx_greeting = yes
smtp_skip_quit_response = yes
smtp_starttls_timeout = 300s
smtp_tls_CAfile =
smtp_tls_CApath =
smtp_tls_cert_file =
smtp_tls_cipherlist =
smtp_tls_dcert_file =
smtp_tls_dkey_file = $smtp_tls_dcert_file
smtp_tls_enforce_peername = yes
smtp_tls_key_file = $smtp_tls_cert_file
smtp_tls_loglevel = 0
smtp_tls_note_starttls_offer = no
smtp_tls_per_site =
smtp_tls_session_cache_database =
smtp_tls_session_cache_timeout = 3600s
smtp_use_tls = no
smtpd_banner = $myhostname ESMTP $mail_name
smtpd_client_restrictions =
smtpd_delay_reject = yes
smtpd_enforce_tls = no
smtpd_error_sleep_time = 5s
smtpd_etrn_restrictions =
smtpd_hard_error_limit = 100
smtpd_helo_required = no
smtpd_helo_restrictions =
smtpd_history_flush_threshold = 100
smtpd_junk_command_limit = 100
smtpd_noop_commands =
smtpd_null_access_lookup_key = <>
smtpd_recipient_limit = 1000
smtpd_recipient_restrictions = check_client_access btree:/etc/postfix/dracd, permit_mynetworks, check_relay_domains
smtpd_restriction_classes =
smtpd_sasl_auth_enable = no
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_security_options = noanonymous
smtpd_sender_login_maps =
smtpd_sender_restrictions =
smtpd_soft_error_limit = 10
smtpd_timeout = 300s
smtpd_tls_CAfile = /etc/ssl/postfix-cert.pem
smtpd_tls_CApath =
smtpd_tls_ask_ccert = no
smtpd_tls_auth_only = no
smtpd_tls_ccert_verifydepth = 5
smtpd_tls_cert_file = /etc/ssl/postfix-cert.pem
smtpd_tls_cipherlist =
smtpd_tls_dcert_file =
smtpd_tls_dh1024_param_file =
smtpd_tls_dh512_param_file =
smtpd_tls_dkey_file = $smtpd_tls_dcert_file
smtpd_tls_key_file = /etc/ssl/postfix-key.pem
smtpd_tls_loglevel = 0
smtpd_tls_received_header = no
smtpd_tls_req_ccert = no
smtpd_tls_session_cache_database =
smtpd_tls_session_cache_timeout = 3600s
smtpd_tls_wrappermode = no
smtpd_use_tls = yes
soft_bounce = no
stale_lock_time = 500s
strict_rfc821_envelopes = no
sun_mailtool_compatibility = no
swap_bangpath = yes
syslog_facility = mail
syslog_name = postfix
tls_daemon_random_bytes = 32
tls_daemon_random_source =
tls_random_bytes = 32
tls_random_exchange_name = ${config_directory}/prng_exch
tls_random_prng_update_period = 60s
tls_random_reseed_period = 3600s
tls_random_source =
transport_maps = hash:/etc/postfix/transport
transport_retry_time = 60s
trigger_timeout = 10s
undisclosed_recipients_header = To: undisclosed-recipients:;
unknown_address_reject_code = 450
unknown_client_reject_code = 450
unknown_hostname_reject_code = 450
verp_delimiter_filter = -=+
virtual_gid_maps =
virtual_mailbox_base =
virtual_mailbox_limit = 51200000
virtual_mailbox_lock = fcntl
virtual_mailbox_maps =
virtual_maps = ldap:ldapsource
virtual_minimum_uid = 100
virtual_uid_maps =