hello
could somebody with experience let me know the dovecot config file settings to handle around 1500 simultaneous connections over pop3 and 1500 connection over imap simultaneously.
my server
server configuration hex core processor, 16 gb ram 1 X 600 gb 15 k rpm for main drive and 2 X 2000 gb hdd for data (No raid)
thanks rajesh
my current config file
settings as such # 2.2.7: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-431.29.2.el6.x86_64 x86_64 CentOS release 6.5 (Final) # NOTE: Send doveconf -n output instead when asking for help. auth_anonymous_username = anonymous auth_cache_negative_ttl = 0 auth_cache_size = 0 auth_cache_ttl = 0 auth_debug = no auth_debug_passwords = yes auth_default_realm = auth_failure_delay = 2 secs auth_gssapi_hostname = auth_krb5_keytab = auth_master_user_separator = auth_mechanisms = plain login digest-md5 cram-md5 auth_proxy_self = auth_realms = auth_socket_path = auth-userdb auth_ssl_require_client_cert = no auth_ssl_username_from_cert = no auth_use_winbind = no auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@ auth_username_format = %Lu auth_username_translation = auth_verbose = no auth_verbose_passwords = no auth_winbind_helper_path = /usr/bin/ntlm_auth auth_worker_max_count = 30 base_dir = /var/run/dovecot config_cache_size = 1 M debug_log_path = default_client_limit = 1000 default_idle_kill = 1 mins default_internal_user = dovecot default_login_user = vpopmail default_process_limit = 100 default_vsz_limit = 256 M deliver_log_format = msgid=%m: %$ dict_db_config = director_doveadm_port = 0 director_mail_servers = director_servers = director_user_expire = 15 mins director_username_hash = %u disable_plaintext_auth = no dotlock_use_excl = yes doveadm_allowed_commands = doveadm_password = doveadm_port = 0 doveadm_socket_path = doveadm-server doveadm_worker_count = 0 dsync_alt_char = _ dsync_remote_cmd = ssh -l%{login} %{host} doveadm dsync-server -u%u -U first_valid_gid = 89 first_valid_uid = 89 hostname = imap_capability = imap_client_workarounds = imap_id_log = imap_id_send = name * imap_idle_notify_interval = 2 mins imap_logout_format = in=%i out=%o imap_max_line_length = 64 k imap_metadata = no imap_urlauth_host = imap_urlauth_logout_format = in=%i out=%o imap_urlauth_port = 143 imapc_features = imapc_host = imapc_list_prefix = imapc_master_user = imapc_max_idle_time = 29 mins imapc_password = imapc_port = 143 imapc_rawlog_dir = imapc_ssl = no imapc_ssl_verify = yes imapc_user = import_environment = TZ DEBUG_OUTOFMEM info_log_path = instance_name = dovecot last_valid_gid = 0 last_valid_uid = 0 lda_mailbox_autocreate = no lda_mailbox_autosubscribe = no lda_original_recipient_header = libexec_dir = /usr/libexec/dovecot listen = *, :: lmtp_address_translate = lmtp_proxy = no lmtp_rcpt_check_quota = no lmtp_save_to_detail_mailbox = no lock_method = fcntl log_path = /var/log/dovecot.log log_timestamp = "%b %d %H:%M:%S " login_access_sockets = login_greeting = ready. login_log_format = %$: %s login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c session=<%{session}> login_trusted_networks = mail_access_groups = mail_always_cache_fields = mail_attachment_dir = mail_attachment_fs = sis posix mail_attachment_hash = %{sha1} mail_attachment_min_size = 128 k mail_attribute_dict = mail_cache_fields = flags mail_cache_min_mail_count = 0 mail_chroot = mail_debug = no mail_fsync = optimized mail_full_filesystem_access = no mail_gid = mail_home = mail_location = mail_log_prefix = "%s(%u): " mail_max_keyword_length = 50 mail_max_lock_timeout = 0 mail_max_userip_connections = 10 mail_never_cache_fields = imap.envelope mail_nfs_index = no mail_nfs_storage = no mail_plugin_dir = /usr/lib64/dovecot mail_plugins = " quota" mail_prefetch_count = 0 mail_privileged_group = mail_save_crlf = no mail_shared_explicit_inbox = no mail_temp_dir = /tmp mail_temp_scan_interval = 1 weeks mail_uid = mailbox_idle_check_interval = 30 secs mailbox_list_index = no maildir_broken_filename_sizes = no maildir_copy_with_hardlinks = yes maildir_stat_dirs = no maildir_very_dirty_syncs = no managesieve_client_workarounds = managesieve_implementation_string = Dovecot Pigeonhole managesieve_logout_format = bytes=%i/%o managesieve_max_compile_errors = 5 managesieve_max_line_length = 65536 managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave master_user_separator = mbox_dirty_syncs = yes mbox_dotlock_change_timeout = 2 mins mbox_lazy_writes = yes mbox_lock_timeout = 5 mins mbox_md5 = apop3d mbox_min_index_size = 0 mbox_read_locks = fcntl mbox_very_dirty_syncs = no mbox_write_locks = dotlock fcntl mdbox_preallocate_space = no mdbox_rotate_interval = 0 mdbox_rotate_size = 2 M mmap_disable = no namespace { disabled = no hidden = no ignore_on_failure = no inbox = yes list = yes location = prefix = separator = . subscriptions = yes type = private } passdb { args = cache_key=%u webmail=127.0.0.1 default_fields = deny = no driver = vpopmail master = no override_fields = pass = no result_failure = continue result_internalfail = continue result_success = return-ok skip = never } plugin { quota = maildir:ignore=Trash quota_rule = ?:storage=0 } pop3_client_workarounds = pop3_deleted_flag = pop3_enable_last = no pop3_fast_size_lookups = no pop3_lock_session = no pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s pop3_no_flag_updates = no pop3_reuse_xuidl = no pop3_save_uidl = no pop3_uidl_duplicates = allow pop3_uidl_format = %08Xu%08Xv pop3c_host = pop3c_master_user = pop3c_password = pop3c_port = 110 pop3c_rawlog_dir = pop3c_ssl = no pop3c_ssl_verify = yes pop3c_user = %u postmaster_address = protocols = imap pop3 quota_full_tempfail = no recipient_delimiter = + rejection_reason = Your message to <%t> was automatically rejected:%n%r rejection_subject = Rejected: %s replication_full_sync_interval = 1 days replication_max_conns = 10 replicator_host = replicator replicator_port = 0 sendmail_path = /usr/sbin/sendmail service aggregator { chroot = . client_limit = 0 drop_priv_before_exec = no executable = aggregator extra_groups = fifo_listener replication-notify-fifo { group = mode = 0600 user = } group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 0 type = unix_listener replication-notify { group = mode = 0600 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service anvil { chroot = empty client_limit = 0 drop_priv_before_exec = no executable = anvil extra_groups = group = idle_kill = 4294967295 secs privileged_group = process_limit = 1 process_min_avail = 1 protocol = service_count = 0 type = anvil unix_listener anvil-auth-penalty { group = mode = 0600 user = } unix_listener anvil { group = mode = 0600 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service auth-worker { chroot = client_limit = 1 drop_priv_before_exec = no executable = auth -w extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 1 type = unix_listener auth-worker { group = mode = 0600 user = $default_internal_user } user = vsz_limit = 18446744073709551615 B } service auth { chroot = client_limit = 0 drop_priv_before_exec = no executable = auth extra_groups = group = idle_kill = 0 privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener auth-client { group = mode = 0600 user = $default_internal_user } unix_listener auth-login { group = mode = 0600 user = $default_internal_user } unix_listener auth-master { group = mode = 0600 user = } unix_listener auth-userdb { group = mode = 0666 user = $default_internal_user } unix_listener login/login { group = mode = 0666 user = } unix_listener token-login/tokenlogin { group = mode = 0666 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service config { chroot = client_limit = 0 drop_priv_before_exec = no executable = config extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 0 type = config unix_listener config { group = mode = 0600 user = } user = vsz_limit = 18446744073709551615 B } service dict { chroot = client_limit = 1 drop_priv_before_exec = no executable = dict extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 0 type = unix_listener dict { group = mode = 0600 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service director { chroot = . client_limit = 0 drop_priv_before_exec = no executable = director extra_groups = fifo_listener login/proxy-notify { group = mode = 00 user = } group = idle_kill = 4294967295 secs privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener director-admin { group = mode = 0600 user = } unix_listener login/director { group = mode = 00 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service dns_client { chroot = client_limit = 1 drop_priv_before_exec = no executable = dns-client extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 0 type = unix_listener dns-client { group = mode = 0666 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service doveadm { chroot = client_limit = 1 drop_priv_before_exec = no executable = doveadm-server extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 1 type = unix_listener doveadm-server { group = mode = 0600 user = } user = vsz_limit = 18446744073709551615 B } service imap-login { chroot = login client_limit = 0 drop_priv_before_exec = no executable = imap-login extra_groups = group = idle_kill = 0 inet_listener imap { address = port = 143 reuse_port = no ssl = no } inet_listener imaps { address = port = 993 reuse_port = no ssl = yes } privileged_group = process_limit = 256 process_min_avail = 50 protocol = imap service_count = 1 type = login user = $default_login_user vsz_limit = 18446744073709551615 B } service imap-urlauth-login { chroot = token-login client_limit = 0 drop_priv_before_exec = no executable = imap-urlauth-login extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = imap service_count = 1 type = login unix_listener imap-urlauth { group = mode = 0666 user = } user = $default_login_user vsz_limit = 18446744073709551615 B } service imap-urlauth-worker { chroot = client_limit = 1 drop_priv_before_exec = no executable = imap-urlauth-worker extra_groups = group = idle_kill = 0 privileged_group = process_limit = 1024 process_min_avail = 0 protocol = imap service_count = 1 type = unix_listener imap-urlauth-worker { group = mode = 0600 user = $default_internal_user } user = vsz_limit = 18446744073709551615 B } service imap-urlauth { chroot = client_limit = 1 drop_priv_before_exec = no executable = imap-urlauth extra_groups = group = idle_kill = 0 privileged_group = process_limit = 1024 process_min_avail = 0 protocol = imap service_count = 1 type = unix_listener token-login/imap-urlauth { group = mode = 0666 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service imap { chroot = client_limit = 1 drop_priv_before_exec = no executable = imap extra_groups = group = idle_kill = 0 privileged_group = process_limit = 2048 process_min_avail = 50 protocol = imap service_count = 1 type = unix_listener login/imap { group = mode = 0666 user = } user = vsz_limit = 512 M } service indexer-worker { chroot = client_limit = 1 drop_priv_before_exec = no executable = indexer-worker extra_groups = group = idle_kill = 0 privileged_group = process_limit = 10 process_min_avail = 0 protocol = service_count = 0 type = unix_listener indexer-worker { group = mode = 0600 user = $default_internal_user } user = vsz_limit = 18446744073709551615 B } service indexer { chroot = client_limit = 0 drop_priv_before_exec = no executable = indexer extra_groups = group = idle_kill = 0 privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener indexer { group = mode = 0666 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } service ipc { chroot = empty client_limit = 0 drop_priv_before_exec = no executable = ipc extra_groups = group = idle_kill = 0 privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener ipc { group = mode = 0600 user = } unix_listener login/ipc-proxy { group = mode = 0600 user = $default_login_user } user = $default_internal_user vsz_limit = 18446744073709551615 B } service lmtp { chroot = client_limit = 1 drop_priv_before_exec = no executable = lmtp extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = lmtp service_count = 0 type = unix_listener lmtp { group = mode = 0666 user = } user = vsz_limit = 18446744073709551615 B } service log { chroot = client_limit = 0 drop_priv_before_exec = no executable = log extra_groups = group = idle_kill = 4294967295 secs privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = log unix_listener log-errors { group = mode = 0600 user = } user = vsz_limit = 18446744073709551615 B } service managesieve-login { chroot = login client_limit = 0 drop_priv_before_exec = no executable = managesieve-login extra_groups = group = idle_kill = 0 inet_listener sieve { address = port = 4190 reuse_port = no ssl = no } privileged_group = process_limit = 0 process_min_avail = 0 protocol = sieve service_count = 1 type = login user = $default_login_user vsz_limit = 18446744073709551615 B } service managesieve { chroot = client_limit = 1 drop_priv_before_exec = no executable = managesieve extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = sieve service_count = 1 type = unix_listener login/sieve { group = mode = 0666 user = } user = vsz_limit = 18446744073709551615 B } service pop3-login { chroot = login client_limit = 0 drop_priv_before_exec = no executable = pop3-login extra_groups = group = idle_kill = 0 inet_listener pop3 { address = port = 110 reuse_port = no ssl = no } inet_listener pop3s { address = port = 995 reuse_port = no ssl = yes } privileged_group = process_limit = 256 process_min_avail = 25 protocol = pop3 service_count = 1 type = login user = $default_login_user vsz_limit = 18446744073709551615 B } service pop3 { chroot = client_limit = 1 drop_priv_before_exec = no executable = pop3 extra_groups = group = idle_kill = 0 privileged_group = process_limit = 256 process_min_avail = 25 protocol = pop3 service_count = 1 type = unix_listener login/pop3 { group = mode = 0666 user = } user = vsz_limit = 18446744073709551615 B } service replicator { chroot = client_limit = 0 drop_priv_before_exec = no executable = replicator extra_groups = group = idle_kill = 4294967295 secs privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener replicator-doveadm { group = mode = 00 user = $default_internal_user } unix_listener replicator { group = mode = 0600 user = $default_internal_user } user = vsz_limit = 18446744073709551615 B } service ssl-params { chroot = client_limit = 0 drop_priv_before_exec = no executable = ssl-params extra_groups = group = idle_kill = 0 privileged_group = process_limit = 0 process_min_avail = 0 protocol = service_count = 0 type = startup unix_listener login/ssl-params { group = mode = 0666 user = } unix_listener ssl-params { group = mode = 0666 user = } user = vsz_limit = 18446744073709551615 B } service stats { chroot = empty client_limit = 0 drop_priv_before_exec = no executable = stats extra_groups = fifo_listener stats-mail { group = mode = 0600 user = } group = idle_kill = 4294967295 secs privileged_group = process_limit = 1 process_min_avail = 0 protocol = service_count = 0 type = unix_listener stats { group = mode = 0600 user = } user = $default_internal_user vsz_limit = 18446744073709551615 B } shutdown_clients = yes ssl = yes ssl_ca = ssl_cert = :backend=%q default_fields = driver = vpopmail override_fields = } valid_chroot_dirs = verbose_proctitle = no verbose_ssl = no version_ignore = no protocol imap { imap_client_workarounds = delay-newmail mail_max_userip_connections = 200 mail_plugins = " quota imap_quota" } protocol pop3 { mail_max_userip_connections = 40 pop3_client_workarounds = outlook-no-nuls oe-ns-eoh pop3_fast_size_lookups = yes pop3_lock_session = no pop3_no_flag_updates = yes }