我的邮件服务器正在运行：
- Postfix 3.1
- Dovecot 2.2.22
- MySQL 5.7
- Ubuntu 16.04
我配置了每个用户的配额，从邮件数据库用户表的以下列中读取quota：
dovecot-sql.conf.ext
driver = mysql
connect = host=127.0.0.1 dbname=mail user=admin password=XIOVwxasxvD
default_pass_scheme = SHA512-CRYPT
user_query = SELECT CONCAT('/home/vmail/',CONCAT(SUBSTRING_INDEX(email,'@',-1),'/',SUBSTRING_INDEX(email,'@',1))) AS home, 5000 AS uid, 5000 AS gid, concat('*:bytes=', quota) AS quota_rule FROM users WHERE email='%u'
password_query = SELECT email as user, password, 5000 AS userdb_uid, 5000 AS userdb_gid, concat('*:bytes=', quota) AS userdb_quota_rule FROM users WHERE email='%u';
我进行了以下配置，以启用 80% 和 95% 的配额警告，并将宽限配额设置为 10%，每个用户的最大配额为 50 MB，
conf.d/90-quota.conf：
plugin {
quota_rule = *:bytes=1G
quota_rule2 = Trash:storage=+100M
quota_rule3 = Sent:storage=+100M
}
plugin {
quota_warning = storage=95%% quota-warning 95 %u
quota_warning2 = storage=80%% quota-warning 80 %u
}
service quota-warning {
executable = script /usr/local/bin/quota-warning.sh
user = vmail
unix_listener quota-warning {
user = vmail
}
}
plugin {
quota = maildir:User quota
}
plugin {
quota_grace = 10%%
quota_grace = 50M
}
plugin {
quota_over_flag_value = TRUE
quota_over_script = quota-warning mismatch %u
}
警告消息工作正常，但一旦用户达到“101%”配额大小，它会拒绝任何新邮件，并向发件人显示“超出配额”错误消息，而不应用宽限配额配置，
在调试模式日志中我得到：
Jul 12 18:48:57 mail postfix/smtp[23827]: 22A7FE884: to=<[email protected]>, relay=127.0.0.1[127.0.0.1]:10024, conn_use=178, delay=17, delays=0.01/16/0.01/1.7, 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 490A8D627)
Jul 12 18:48:57 mail postfix/qmgr[25020]: 22A7FE884: removed
Jul 12 18:48:57 mail postfix/pickup[24689]: 5C653E898: uid=5000 from=<[email protected]>
Jul 12 18:48:57 mail postfix/cleanup[25288]: warning: connect to Milter service inet:localhost:9001: Cannot assign requested address
Jul 12 18:48:57 mail postfix/cleanup[25288]: 5C653E898: message-id=<[email protected]>
Jul 12 18:48:57 mail postfix/qmgr[25020]: 5C653E898: from=<[email protected]>, size=418, nrcpt=1 (queue active)
Jul 12 18:48:58 mail postfix/smtpd[25228]: 389E6D627: client=localhost[127.0.0.1]
Jul 12 18:48:58 mail postfix/cleanup[25288]: 389E6D627: message-id=<[email protected]>
Jul 12 18:48:58 mail postfix/qmgr[25020]: 389E6D627: from=<[email protected]>, size=877, nrcpt=1 (queue active)
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota root: name=User quota backend=maildir args=
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota rule: root=User quota mailbox=* bytes=1073741824 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota rule: root=User quota mailbox=Trash bytes=+104857600 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota rule: root=User quota mailbox=Sent bytes=+104857600 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota warning: bytes=1020054732 (95%) messages=0 reverse=no command=quota-warning 95 raw mail user
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota warning: bytes=858993459 (80%) messages=0 reverse=no command=quota-warning 80 raw mail user
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: Quota grace: root=User quota bytes=52428800
Jul 12 18:48:58 mail dovecot: lmtp(24483): Debug: none: root=, index=, indexpvt=, control=, inbox=, alt=
Jul 12 18:48:58 mail dovecot: lmtp(24483): Connect from local
Jul 12 18:48:58 mail dovecot: auth: Debug: master in: USER#011104#[email protected]#011service=lmtp
Jul 12 18:48:58 mail dovecot: auth-worker(15471): Debug: sql([email protected]): SELECT CONCAT('/home/vmail/',CONCAT(SUBSTRING_INDEX(email,'@',-1),'/',SUBSTRING_INDEX(email,'@',1))) AS home, 5000 AS uid, 5000 AS gid, concat('*:bytes=', quota) AS quota_rule FROM users WHERE email='[email protected]'
Jul 12 18:48:58 mail dovecot: auth: Debug: userdb out: USER#011104#[email protected]#011home=/home/vmail/mydomain.com/user#011uid=5000#011gid=5000#011quota_rule=*:bytes=102400
Jul 12 18:48:58 mail dovecot: lmtp([email protected]): Debug: auth input: [email protected] home=/home/vmail/mydomain.com/user uid=5000 gid=5000 quota_rule=*:bytes=102400
Jul 12 18:48:58 mail dovecot: lmtp([email protected]): Debug: Added userdb setting: plugin/quota_rule=*:bytes=102400
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Effective uid=5000, gid=5000, home=/home/vmail/mydomain.com/user
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota root: name=User quota backend=maildir args=
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota rule: root=User quota mailbox=* bytes=102400 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota rule: root=User quota mailbox=Trash bytes=+104857600 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota rule: root=User quota mailbox=Sent bytes=+104857600 messages=0
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota warning: bytes=97280 (95%) messages=0 reverse=no command=quota-warning 95 [email protected]
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota warning: bytes=81920 (80%) messages=0 reverse=no command=quota-warning 80 [email protected]
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Quota grace: root=User quota bytes=52428800
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: Namespace inbox: type=private, prefix=, sep=, inbox=yes, hidden=no, list=yes, subscriptions=yes location=maildir:/home/vmail/mydomain.com/user
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: maildir++: root=/home/vmail/mydomain.com/user, index=, indexpvt=, control=, inbox=/home/vmail/mydomain.com/user, alt=
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: quota: quota_over_flag check: STORAGE ret=1 value=101 limit=100
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: quota: quota_over_flag check: MESSAGE ret=0 value=99 limit=0
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: quota: quota_over_flag=0((null)) vs currently overquota=1
Jul 12 18:48:58 mail dovecot: lmtp(24483, [email protected]): Debug: quota: Executing warning: quota-warning mismatch [email protected]
Jul 12 18:48:58 mail dovecot: lmtp([email protected]): 4GRuG8FuZlmjXwAAPxyzFw: msgid=<[email protected]>: save failed to INBOX: Quota exceeded (mailbox for user is full)
答案1
Dovecotgrace_quota无法像您预期的那样工作。从Dovecot 配额手册：
在 v2.2+ 中，默认情况下，最后一封邮件会使用户超出配额。这很有用，因为它可以让用户真正明确地超出配额，而不是让最后几封较大的邮件失败，并让一些较小的邮件通过。当然，不应该允许最后一封邮件使用户大大超出配额，因此在 v2.2+ 中，默认情况下此限制是用户配额限制的 10%。（在 v2.1 中，默认情况下禁用此功能。）
换句话说，quota_grace可以避免出现令人困惑的情况，即由于邮件超出用户配额而被拒绝（大型邮件），但随后成功发送了较新的（和较小的）邮件（因为它们仍然符合用户的配额）。使用quota_grace，Dovecot 允许发送最后一封大型邮件，但随后会阻止其他邮件，因为用户超出了 100% 的配额使用率。
Dovecot 不知道您正在寻找的功能 - 虽然您可以简单地发送具有转移配额使用值的邮件（例如，发送“您使用了 100％ 的配额”尽管用户实际上仍为 90％并相应地调整实际限制），但实际配额仍然通过 IMAP 传输，用于显示您的配额使用情况的邮件客户端。