Dovecot 報告沒有 SASL 身份驗證機制

在我在 Ubuntu 上使用 Postfix 和 Dovecot 設置郵件伺服器的過程中，我現在可以將郵件發送到其他域。但是，我不能從別人那裡得到。在它讀取的日誌中

Jun 14 09:34:35 postfix/smtpd[27426]: connect from mail-wg0-f44.google.com[74.125.82.44]
Jun 14 09:34:35 postfix/smtpd[27426]: warning: SASL: Connect to private/auth failed: Permission denied
Jun 14 09:34:35 postfix/smtpd[27426]: fatal: no SASL authentication mechanisms
Jun 14 09:34:36 postfix/master[18697]: warning: process /usr/lib/postfix/smtpd pid 27426 exit status 1
Jun 14 09:34:36 postfix/master[18697]: warning: /usr/lib/postfix/smtpd: bad command startup -- throttling

我不知道我的配置哪裡有錯誤。該文件auth存在如下：

srw-rw---- 1 vmail vmail 0 Jun 14 08:51 /var/spool/postfix/private/auth

這是輸出postconf -n

alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
config_directory = /etc/postfix
dovecot_destination_recipient_limit = 1
inet_interfaces = all
mailbox_size_limit = 0
mydestination = $myhostname, localhost, localhost.$mydomain
myhostname = mail.example.com
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
myorigin = /etc/mailname
readme_directory = no
recipient_delimiter = +
relayhost =
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
smtpd_data_restrictions = reject_multi_recipient_bounce
smtpd_helo_required = yes
smtpd_recipient_restrictions = reject_non_fqdn_recipient reject_non_fqdn_sender reject_unknown_recipient_domain reject_unknown_sender_domain permit_mynetworks reject_sender_login_mismatch reject_unauth_destination check_recipient_access hash:/etc/postfix/roleaccount_exceptions reject_multi_recipient_bounce reject_non_fqdn_helo_hostname reject_invalid_helo_hostname check_helo_access pcre:/etc/postfix/helo_checks check_sender_mx_access cidr:/etc/postfix/bogus_mx permit
smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
smtpd_sasl_auth_enable = yes
smtpd_sasl_path = private/auth
smtpd_sasl_type = dovecot
smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_use_tls = yes
virtual_alias_maps = proxy:ldap:/etc/postfix/virtual_aliases.cf
virtual_gid_maps = static:10000
virtual_mailbox_domains = $mydomain
virtual_transport = dovecot
virtual_uid_maps = static:10000

和其中之一dovecot -n

# 2.2.9: /etc/dovecot/dovecot.conf
# OS: Linux 3.13.0-042stab106.6 x86_64 Ubuntu 14.04.2 LTS ext4
auth_debug = yes
auth_mechanisms = plain login
auth_verbose = yes
mail_location = maildir:/srv/mail/%n
namespace inbox {
 inbox = yes
 location =
 mailbox Drafts {
   special_use = \Drafts
 }
 mailbox Junk {
   special_use = \Junk
 }
 mailbox Sent {
   special_use = \Sent
 }
 mailbox "Sent Messages" {
   special_use = \Sent
 }
 mailbox Trash {
   special_use = \Trash
 }
 prefix =
}
passdb {
 args = /etc/dovecot/dovecot-ldap.conf.ext
 driver = ldap
}
protocols = " imap"
service auth {
 unix_listener /var/spool/postfix/private/auth {
   group = vmail
   mode = 0660
   user = vmail
 }
 unix_listener auth-master {
   mode = 0600
   user = vmail
 }
}
ssl_cert = </etc/dovecot/dovecot.pem
ssl_key = </etc/dovecot/private/dovecot.pem
userdb {
 args = /etc/dovecot/dovecot-ldap.conf.ext
 driver = ldap
}
protocol lda {
 postmaster_address = postmaster@example.com
}

非常感謝任何提示。提前感謝您的幫助。

由於不同的 uid 和嚴格的權限，您postfix無法訪問 auth-daemon 套接字。最簡單的方法是將權限更改為 666 (rw-rw-rw-) 並檢查身份驗證是否已修復。然後您必須處理程序 UID/使用者以將身份驗證限制為僅郵件軟體。

service auth {
 unix_listener /var/spool/postfix/private/auth {
   group = vmail
   mode = 0666
#   mode = 0660
   user = vmail
 }
 unix_listener auth-master {
   mode = 0666
#   mode = 0600
   user = vmail
 }
}

引用自：https://serverfault.com/questions/698885