dovecot error

hello all

we were seeing an error as such in dovecot.log for the first time

we use sogo for active sync

dovecot: master: Warning: service(dict): process_limit (100) reached, client connections are being dropped

once we restarted sogo service this issue got resolved

could someone please guide us on how to resolve the above

please find below dovecot config file

####################################### # More details about Dovecot settings: # - http://wiki2.dovecot.org/ # - http://wiki2.dovecot.org/Variables

# Listen addresses. # - '*' means all available IPv4 addresses. # - '[::]' means all available IPv6 addresses. # Listen on all available addresses by default listen = *

#base_dir = /var/run/dovecot mail_plugins = quota mailbox_alias acl mail_log notify stats

# Enabled mail protocols. protocols = pop3 imap sieve lmtp

default_client_limit = 2400

# User/group who owns the message files: mail_uid = 2000 mail_gid = 2000

# Assign uid to virtual users. first_valid_uid = 2000 last_valid_uid = 2000

# Logging. Reference: http://wiki2.dovecot.org/Logging # # Use syslog syslog_facility = local5 # Log file path if we use internal log system #log_path = /var/log/dovecot/dovecot.log

# Debug #mail_debug = yes #auth_verbose = yes #auth_debug = yes #auth_debug_passwords = yes # Possible values: no, plain, sha1. #auth_verbose_passwords = no

# SSL: Global settings. # Refer to wiki site for per protocol, ip, server name SSL settings: # http://wiki2.dovecot.org/SSL/DovecotConfiguration ssl_protocols = !SSLv3 ssl = required verbose_ssl = no #ssl_ca =

# Fix 'The Logjam Attack' ssl_cipher_list = ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5 ssl_prefer_server_ciphers = yes

# With disable_plaintext_auth=yes AND ssl=required, STARTTLS is mandatory. # Set disable_plaintext_auth=no AND ssl=yes to allow plain password transmitted # insecurely. disable_plaintext_auth = no ssl=yes

# Allow plain text password per IP address/net #remote 192.168.0.0/24 { # disable_plaintext_auth = no #}

# Mail location and mailbox format. mail_location = maildir:%Lh/Maildir/:INDEX=%Lh/Maildir/

# Authentication related settings. # Append this domain name if client gives empty realm. #auth_default_realm = aaaonlinux.net

# Authentication mechanisms. auth_mechanisms = PLAIN LOGIN

# Limits the number of users that can be logging in at the same time. # Default is 100. This can be overridden by process_limit = in # service [protocol] block. # e.g. # protocol imap-login { # ... # process_limit = 500 # } #default_process_limit = 100

# Mail delivery log format deliver_log_format = from=%{from}, envelope_sender=%{from_envelope}, subject=%{subject}, msgid=%m, size=%{size}, %$

service auth { unix_listener /var/spool/postfix/private/dovecot-auth { user = postfix group = postfix mode = 0666 } unix_listener auth-master { user = vmail group = vmail mode = 0666 } unix_listener auth-userdb { user = vmail group = vmail mode = 0660 } }

# LMTP server (Local Mail Transfer Protocol). # Reference: http://wiki2.dovecot.org/LMTP service lmtp { user = vmail

# For higher volume sites, it may be desirable to increase the number of
# active listener processes. A range of 5 to 20 is probably good for most
# sites.
process_min_avail = 5

# Logging.
# Require 'log_path =' in 'protocol lmtp {}' block.
executable = lmtp -L

# Listening on socket file and TCP
unix_listener /var/spool/postfix/private/dovecot-lmtp {
    user = postfix
    group = postfix
    mode = 0600
}

inet_listener lmtp {
    # Listen on localhost (ipv4)
    address = 127.0.0.1
    port = 24
}

}

# Virtual mail accounts. userdb { args = /etc/dovecot/dovecot-mysql.conf driver = sql } passdb { args = /etc/dovecot/dovecot-mysql.conf driver = sql }

# Master user. # Master users are able to log in as other users. It's also possible to # directly log in as any user using a master password, although this isn't # recommended. # Reference: http://wiki2.dovecot.org/Authentication/MasterUsers auth_master_user_separator = * passdb { driver = passwd-file args = /etc/dovecot/dovecot-master-users master = yes }

plugin { # Quota configuration. # Reference: http://wiki2.dovecot.org/Quota/Configuration quota = dict:user::proxy::quotadict

# Set default quota rule if no quota returned from SQL/LDAP query.
#quota_rule = *:storage=1G
#quota_rule2 = *:messages=0
#quota_rule3 = Trash:storage=1G
#quota_rule4 = Junk:ignore

# Quota warning.
#
# If user suddenly receives a huge mail and the quota jumps from
# 85% to 95%, only the 95% script is executed.
#
# Only the command for the first exceeded limit is executed, so configure
# the highest limit first.
quota_warning = storage=100%% quota-warning 100 %u
quota_warning2 = storage=95%% quota-warning 95 %u
quota_warning3 = storage=90%% quota-warning 90 %u
quota_warning4 = storage=85%% quota-warning 85 %u

# allow user to become max 10% (or 50 MB) over quota
quota_grace = 10%%
#quota_grace = 50 M

# Custom Quota Exceeded Message.
# You can specify the message directly or read the message from a file.
#quota_exceeded_message = Quota exceeded, please try again later.
#quota_exceeded_message = </path/to/quota_exceeded_message.txt

# Plugin: expire.
#expire = Trash 7 Trash/* 7 Junk 30
#expire_dict = proxy::expire

# ACL and share folder
acl = vfile
acl_shared_dict = proxy::acl

# By default Dovecot doesn't allow using the IMAP "anyone" or
# "authenticated" identifier, because it would be an easy way to spam
# other users in the system. If you wish to allow it,
#acl_anyone = allow

# Pigeonhole managesieve service.
# Reference: http://wiki2.dovecot.org/Pigeonhole/Sieve/Configuration
# Per-user sieve settings.
sieve_dir = ~/sieve
sieve = ~/sieve/dovecot.sieve

# Global sieve settings.
sieve_global_dir = /var/vmail/sieve
# Note: if user has personal sieve script, global sieve rules defined in
#       sieve_default will be ignored. Please use sieve_before or
#       sieve_after instead.
#sieve_default =

sieve_before = /var/vmail/sieve/dovecot.sieve
#sieve_after =

# The maximum number of redirect actions that can be performed during a
# single script execution.
# The meaning of 0 differs based on your version. For pigeonhole-0.3.0 and
# beyond this means that redirect is prohibited. For older versions,
# however, this means that the number of redirects is unlimited.
sieve_max_redirects = 30

# Use recipient as vacation message sender instead of null sender (<>).
sieve_vacation_send_from_recipient = yes

# Reference: http://wiki2.dovecot.org/Plugins/MailboxAlias
mailbox_alias_old = Sent
mailbox_alias_new = Sent Messages
mailbox_alias_old2 = Sent
mailbox_alias_new2 = Sent Items

# Events to log. `autoexpunge` is included in `expunge`
# Defined in https://github.com/dovecot/core/blob/master/src/plugins/mail-log/mail-log-plugin.c
mail_log_events = delete undelete expunge mailbox_delete mailbox_rename
mail_log_fields = uid box msgid size from subject

# stats
#
# how often to session statistics (must be set)
stats_refresh = 30 secs
# track per-IMAP command statistics (optional)
stats_track_cmds = yes

}

service stats { fifo_listener stats-mail { user = vmail mode = 0644 }

inet_listener {
    address = 127.0.0.1
    port = 24242
}

}

service quota-warning { executable = script /usr/local/bin/dovecot-quota-warning.sh unix_listener quota-warning { user = vmail group = vmail mode = 0660 } }

service dict { unix_listener dict { mode = 0660 user = vmail group = vmail } }

dict { #expire = db:/var/lib/dovecot/expire/expire.db quotadict = mysql:/etc/dovecot/dovecot-used-quota.conf acl = mysql:/etc/dovecot/dovecot-share-folder.conf }

protocol lda { # Reference: http://wiki2.dovecot.org/LDA mail_plugins = $mail_plugins sieve lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes

# Log file path if we use internal log system
#log_path = /var/log/dovecot/sieve.log

}

protocol lmtp { # Log file path if we use internal log system #log_path = /var/log/dovecot/lmtp.log

# Plugins
mail_plugins = quota sieve

# Address extension delivery
lmtp_save_to_detail_mailbox = yes
recipient_delimiter = +

}

protocol imap { mail_plugins = $mail_plugins imap_quota imap_acl imap_stats imap_client_workarounds = tb-extra-mailbox-sep

#process_limit = 1000

# Maximum number of IMAP connections allowed for a user from each IP address.
# NOTE: The username is compared case-sensitively.
# Default is 10.
# Increase it to avoid issue like below:
# "Maximum number of concurrent IMAP connections exceeded"
mail_max_userip_connections = 100

}

protocol pop3 { mail_plugins = $mail_plugins pop3_client_workarounds = outlook-no-nuls oe-ns-eoh pop3_uidl_format = %08Xu%08Xv

# Maximum number of IMAP connections allowed for a user from each IP address.
# NOTE: The username is compared case-sensitively.
# Default is 10.
mail_max_userip_connections = 100

#process_limit = 1000

# POP3 logout format string:
#  %i - total number of bytes read from client
#  %o - total number of bytes sent to client
#  %t - number of TOP commands
#  %p - number of bytes sent to client as a result of TOP command
#  %r - number of RETR commands
#  %b - number of bytes sent to client as a result of RETR command
#  %d - number of deleted messages
#  %m - number of messages (before deletion)
#  %s - mailbox size in bytes (before deletion)
# Default format doesn't have 'in=%i, out=%o'.
#pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s, in=%i, out=%o

}

# Login processes. Refer to Dovecot wiki for more details: # http://wiki2.dovecot.org/LoginProcess

################### LAST LOGIN START

protocol imap { # Append plugin name last_login here mail_plugins = last_login }

protocol pop3 { # Append plugin name last_login here mail_plugins = last_login }

dict { # Add this line. For FreeBSD, please replace the path by # /usr/local/etc/dovecot/dovecot-last-login.conf lastlogin = mysql:/etc/dovecot/dovecot-last-login.conf }

plugin { # Add 2 lines last_login_dict = proxy::lastlogin last_login_key = last-login/%s/%u/%d/%r/%l }

################### LAST LOGIN END

# Login processes. Refer to Dovecot wiki for more details: # http://wiki2.dovecot.org/LoginProcess

######################

service imap-login { service_count = 0 process_min_avail = 50 process_limit = 256 }

service imap { process_limit = 2048 process_min_avail = 50 service_count = 1 vsz_limit = 512 M }

########################

service pop3-login { service_count = 0 process_min_avail = 25 process_limit = 256 }

service pop3 { service_count = 1 process_limit = 256 process_min_avail = 25 }

##########################

##############

#service imap-login { #inet_listener imap { # port = 143 #} #inet_listener imaps { # port = 993 # ssl = yes #}

# service_count = 1

# To avoid startup latency for new client connections, set process_min_avail
# to higher than zero. That many idling processes are always kept around
# waiting for new connections.
#process_min_avail = 0

# number of simultaneous IMAP connections

# process_limit = 500

# vsz_limit should be fine at its default 64MB value
#vsz_limit = 64M

#}

#service pop3-login { #inet_listener pop3 { # port = 110 #} #inet_listener pop3s { # port = 995 # ssl = yes #}

# service_count = 1

# number of simultaneous POP3 connections
#process_limit = 500

#} ############## Commented by

service managesieve-login { inet_listener sieve { # Listen on localhost (ipv4) address = 127.0.0.1 port = 4190 } }

namespace { type = private separator = / prefix = inbox = yes

# Refer to document for more details about alias mailbox:
# http://wiki2.dovecot.org/MailboxSettings
#
# Sent
mailbox Sent {
    auto = subscribe
    special_use = \Sent
}
mailbox "Sent Messages" {
    auto = no
    special_use = \Sent
}
mailbox "Sent Items" {
    auto = no
    special_use = \Sent
}

mailbox Drafts {
    auto = subscribe
    special_use = \Drafts
}

# Trash
mailbox Trash {
    auto = subscribe
    special_use = \Trash
}

mailbox "Deleted Messages" {
    auto = no
    special_use = \Trash
}

# Junk
mailbox Junk {
    auto = subscribe
    special_use = \Junk
}
mailbox Spam {
    auto = no
    special_use = \Junk
}
mailbox "Junk E-mail" {
    auto = no
    special_use = \Junk
}

# Archive
mailbox Archive {
    auto = no
    special_use = \Archive
}
mailbox Archives {
    auto = no
    special_use = \Archive
}

}

namespace { type = shared separator = / prefix = Shared/%%u/ location = maildir:%%Lh/Maildir/:INDEX=%%Lh/Maildir/Shared/%%Ld/%%Ln

# this namespace should handle its own subscriptions or not.
subscriptions = yes
list = children

}

# Public mailboxes. # Refer to Dovecot wiki page for more details: # http://wiki2.dovecot.org/SharedMailboxes/Public #namespace { # type = public # separator = / # prefix = Public/ # location = maildir:/var/vmail/public:CONTROL=%Lh/Maildir/public:INDEXPVT=%Lh/Maildir/public # # # Allow users to subscribe to the public folders. # subscriptions = yes #}

!include_try /etc/dovecot/iredmail/*.conf

##################################

many thanks rajesh