Fail2ban: fail2banログレベルを理解する

環境：

• Fail2Banバージョン（可能な配布サフィックスを含む）：Fail2Ban v0.9.6-2
• リリース名/バージョンを含むOS：Debian Stretch
• [x] OS /配信メカニズムを介してインストールされたFail2Ban
• [x]コードベースに追加の外部パッチを適用していません

問題：

わかりませんが、Fail2banが期待しているログレベルの形式は、両方のようです...
基本的に、ログレベルを数値で設定すると、構成が拒否され、上記のエラーメッセージが表示されます。
しかし、文字列を使用してログレベル（エラー、警告、通知、情報、デバッグ）を設定すると、すべてが正しく機能します。
私の理解では、fail2banはfail2ban.confファイルで両方の形式をサポートしていますが、これは私が経験していることではありません。

再現する手順

/etc/fail2ban/fail2ban.conf loglevel = 1を設定します

予想される行動

fail2ban.logに表示されるエラーメッセージのみが表示されることを期待しています

観察された行動

fail2ban-client reloadにエラーメッセージERROR NOK: ('Invalid log level',)が表示されました

追加情報

これは、fail2banをセットアップするためのサードパーティツール（ Webmin＃742 ）に影響を与えています。
それがfail2banの問題なのかDebianパッケージメンテナの問題なのか100％わからない...

fail2ban構成リーダーは、文字列＃657がここに影響を与えるかどうかわからないことを期待しています...

構成、ダンプ、およびその他の役立つ抜粋

/ etc / fail2ban /構成に対して行われたカスタマイズ

この構成は機能していません。 loglevelを参照してください

# Fail2Ban main configuration file
#
# Comments: use '#' for comment lines and ';' (following a space) for inline comments
#
# Changes:  in most of the cases you should not modify this
#           file, but provide customizations in fail2ban.local file, e.g.:
#
# [Definition]
# loglevel = DEBUG
#

[Definition]

# Option: loglevel
# Notes.: Set the log level output.
#         CRITICAL
#         ERROR
#         WARNING
#         NOTICE
#         INFO
#         DEBUG
# Values: [ LEVEL ]  Default: ERROR
#
loglevel = 1

# Option: logtarget
# Notes.: Set the log target. This could be a file, SYSLOG, STDERR or STDOUT.
#         Only one log target can be specified.
#         If you change logtarget from the default value and you are
#         using logrotate -- also adjust or disable rotation in the
#         corresponding configuration file
#         (e.g. /etc/logrotate.d/fail2ban on Debian systems)
# Values: [ STDOUT | STDERR | SYSLOG | FILE ]  Default: STDERR
#
logtarget = /var/log/fail2ban.log

# Option: syslogsocket
# Notes: Set the syslog socket file. Only used when logtarget is SYSLOG
#        auto uses platform.system() to determine predefined paths
# Values: [ auto | FILE ]  Default: auto
syslogsocket = auto

# Option: socket
# Notes.: Set the socket file. This is used to communicate with the daemon. Do
#         not remove this file when Fail2ban runs. It will not be possible to
#         communicate with the server afterwards.
# Values: [ FILE ]  Default: /var/run/fail2ban/fail2ban.sock
#
socket = /var/run/fail2ban/fail2ban.sock

# Option: pidfile
# Notes.: Set the PID file. This is used to store the process ID of the
#         fail2ban server.
# Values: [ FILE ]  Default: /var/run/fail2ban/fail2ban.pid
#
pidfile = /var/run/fail2ban/fail2ban.pid

# Options: dbfile
# Notes.: Set the file for the fail2ban persistent data to be stored.
#         A value of ":memory:" means database is only stored in memory 
#         and data is lost when fail2ban is stopped.
#         A value of "None" disables the database.
# Values: [ None :memory: FILE ] Default: /var/lib/fail2ban/fail2ban.sqlite3
dbfile = /var/lib/fail2ban/fail2ban.sqlite3

# Options: dbpurgeage
# Notes.: Sets age at which bans should be purged from the database
# Values: [ SECONDS ] Default: 86400 (24hours)
dbpurgeage = 86400

この構成は正しく機能しています

# Fail2Ban main configuration file
#
# Comments: use '#' for comment lines and ';' (following a space) for inline comments
#
# Changes:  in most of the cases you should not modify this
#           file, but provide customizations in fail2ban.local file, e.g.:
#
# [Definition]
# loglevel = DEBUG
#

[Definition]

# Option: loglevel
# Notes.: Set the log level output.
#         CRITICAL
#         ERROR
#         WARNING
#         NOTICE
#         INFO
#         DEBUG
# Values: [ LEVEL ]  Default: ERROR
#
loglevel = INFO

# Option: logtarget
# Notes.: Set the log target. This could be a file, SYSLOG, STDERR or STDOUT.
#         Only one log target can be specified.
#         If you change logtarget from the default value and you are
#         using logrotate -- also adjust or disable rotation in the
#         corresponding configuration file
#         (e.g. /etc/logrotate.d/fail2ban on Debian systems)
# Values: [ STDOUT | STDERR | SYSLOG | FILE ]  Default: STDERR
#
logtarget = /var/log/fail2ban.log

# Option: syslogsocket
# Notes: Set the syslog socket file. Only used when logtarget is SYSLOG
#        auto uses platform.system() to determine predefined paths
# Values: [ auto | FILE ]  Default: auto
syslogsocket = auto

# Option: socket
# Notes.: Set the socket file. This is used to communicate with the daemon. Do
#         not remove this file when Fail2ban runs. It will not be possible to
#         communicate with the server afterwards.
# Values: [ FILE ]  Default: /var/run/fail2ban/fail2ban.sock
#
socket = /var/run/fail2ban/fail2ban.sock

# Option: pidfile
# Notes.: Set the PID file. This is used to store the process ID of the
#         fail2ban server.
# Values: [ FILE ]  Default: /var/run/fail2ban/fail2ban.pid
#
pidfile = /var/run/fail2ban/fail2ban.pid

# Options: dbfile
# Notes.: Set the file for the fail2ban persistent data to be stored.
#         A value of ":memory:" means database is only stored in memory 
#         and data is lost when fail2ban is stopped.
#         A value of "None" disables the database.
# Values: [ None :memory: FILE ] Default: /var/lib/fail2ban/fail2ban.sqlite3
dbfile = /var/lib/fail2ban/fail2ban.sqlite3

# Options: dbpurgeage
# Notes.: Sets age at which bans should be purged from the database
# Values: [ SECONDS ] Default: 86400 (24hours)
dbpurgeage = 86400

/var/log/fail2ban.logファイルの関連部分：

ログレベルが* 1 *に設定されている場合

2017-12-27 06:50:02,125 fail2ban.jail           [8231]: INFO    Jail 'libwww-perl' stopped
2017-12-27 06:50:02,630 fail2ban.jail           [8231]: INFO    Jail 'apache-auth' stopped
2017-12-27 06:50:02,957 fail2ban.jail           [8231]: INFO    Jail 'apache-noscript' stopped
2017-12-27 06:50:03,879 fail2ban.jail           [8231]: INFO    Jail 'WebServerScanner' stopped
2017-12-27 06:50:04,344 fail2ban.jail           [8231]: INFO    Jail 'pass2allow-ftp' stopped
2017-12-27 06:50:05,180 fail2ban.jail           [8231]: INFO    Jail 'php-url-fopen' stopped
2017-12-27 06:50:05,183 fail2ban.transmitter    [8231]: WARNING Command ['set', 'loglevel', '1'] has failed. Received ValueError('Invalid log level',)
2017-12-27 06:50:05,186 fail2ban.server         [8231]: INFO    Changed logging target to /var/log/fail2ban.log for Fail2ban v0.9.6
2017-12-27 06:50:05,187 fail2ban.jail           [8231]: INFO    Creating new jail 'sshd-ddos'
2017-12-27 06:50:05,188 fail2ban.jail           [8231]: INFO    Jail 'sshd-ddos' uses pyinotify {}
2017-12-27 06:50:05,206 fail2ban.jail           [8231]: INFO    Initiated 'pyinotify' backend
2017-12-27 06:50:05,209 fail2ban.actions        [8231]: INFO    Set banTime = 60000
2017-12-27 06:50:05,210 fail2ban.filter         [8231]: INFO    Set jail log file encoding to UTF-8
2017-12-27 06:50:05,213 fail2ban.filter         [8231]: INFO    Set findtime = 600
2017-12-27 06:50:05,216 fail2ban.filter         [8231]: INFO    Added logfile = /var/log/auth.log

ログレベルがINFOに設定されている場合

2017-12-27 06:55:42,222 fail2ban.jail           [8231]: INFO    Jail 'libwww-perl' stopped
2017-12-27 06:55:43,128 fail2ban.jail           [8231]: INFO    Jail 'apache-auth' stopped
2017-12-27 06:55:43,422 fail2ban.jail           [8231]: INFO    Jail 'apache-noscript' stopped
2017-12-27 06:55:44,296 fail2ban.jail           [8231]: INFO    Jail 'WebServerScanner' stopped
2017-12-27 06:55:44,857 fail2ban.jail           [8231]: INFO    Jail 'pass2allow-ftp' stopped
2017-12-27 06:55:45,353 fail2ban.jail           [8231]: INFO    Jail 'php-url-fopen' stopped
2017-12-27 06:55:45,362 fail2ban.server         [8231]: INFO    Changed logging target to /var/log/fail2ban.log for Fail2ban v0.9.6
2017-12-27 06:55:45,367 fail2ban.jail           [8231]: INFO    Creating new jail 'sshd-ddos'
2017-12-27 06:55:45,368 fail2ban.jail           [8231]: INFO    Jail 'sshd-ddos' uses pyinotify {}
2017-12-27 06:55:45,386 fail2ban.jail           [8231]: INFO    Initiated 'pyinotify' backend
2017-12-27 06:55:45,391 fail2ban.filter         [8231]: INFO    Set findtime = 600
2017-12-27 06:55:45,396 fail2ban.filter         [8231]: INFO    Added logfile = /var/log/auth.log

ご入力いただきありがとうございます

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