syslog サーバメモ

syslog サーバ作ったメモ。

OS: CentOS7

rsyslog も logrotate も元から入ってる。

rsyslog

# cat /etc/rsyslog.conf
# rsyslog configuration file

# For more information see /usr/share/doc/rsyslog-*/rsyslog_conf.html
# If you experience problems, see http://www.rsyslog.com/doc/troubleshoot.html

#### MODULES ####

# The imjournal module bellow is now used as a message source instead of imuxsock.
$ModLoad imuxsock # provides support for local system logging (e.g. via logger command)
$ModLoad imjournal # provides access to the systemd journal
#$ModLoad imklog # reads kernel messages (the same are read from journald)
#$ModLoad immark  # provides --MARK-- message capability

# Provides UDP syslog reception
$ModLoad imudp
$UDPServerRun 514

# Provides TCP syslog reception
$ModLoad imtcp
$InputTCPServerRun 514


#### GLOBAL DIRECTIVES ####

# Where to place auxiliary files
$WorkDirectory /var/lib/rsyslog

# Use default timestamp format
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat

# File syncing capability is disabled by default. This feature is usually not required,
# not useful and an extreme performance hit
#$ActionFileEnableSync on

# Include all config files in /etc/rsyslog.d/
$IncludeConfig /etc/rsyslog.d/*.conf

# Turn off message reception via local log socket;
# local messages are retrieved through imjournal now.
$OmitLocalLogging on

# File to store the position in the journal
$IMJournalStateFile imjournal.state


#### RULES ####

# Log all kernel messages to the console.
# Logging much else clutters up the screen.
#kern.*                                                 /dev/console

# Log anything (except mail) of level info or higher.
# Don't log private authentication messages!
*.info;mail.none;authpriv.none;cron.none                /var/log/messages

# The authpriv file has restricted access.
authpriv.*                                              /var/log/secure

# Log all the mail messages in one place.
mail.*                                                  -/var/log/maillog


# Log cron stuff
cron.*                                                  /var/log/cron

# Everybody gets emergency messages
*.emerg                                                 :omusrmsg:*

# Save news errors of level crit and higher in a special file.
uucp,news.crit                                          /var/log/spooler

# Save boot messages also to boot.log
local7.*                                                /var/log/boot.log

$template HostIP-Logs, "/var/log/syslog/%fromhost-ip%/%$year%/%$year%-%$month%-%$day%.messages.log"

*.* -?HostIP-Logs
& stop

# ### begin forwarding rule ###
# The statement between the begin ... end define a SINGLE forwarding
# rule. They belong together, do NOT split them. If you create multiple
# forwarding rules, duplicate the whole block!
# Remote Logging (we use TCP for reliable delivery)
#
# An on-disk queue is created for this action. If the remote host is
# down, messages are spooled to disk and sent when it is up again.
#$ActionQueueFileName fwdRule1 # unique name prefix for spool files
#$ActionQueueMaxDiskSpace 1g   # 1gb space limit (use as much as possible)
#$ActionQueueSaveOnShutdown on # save messages to disk on shutdown
#$ActionQueueType LinkedList   # run asynchronously
#$ActionResumeRetryCount -1    # infinite retries if host is down
# remote host is: name/ip:port, e.g. 192.168.0.1:514, port optional
#*.* @@remote-host:514
# ### end of the forwarding rule ###

$template のところで保存先のファイルを指定。
上の設定で /var/log/syslog/198.51.100.10/2019/2019-09-14.messages.log に保存される。

ログローテート

ファイル名で指定。ワイルドカードも使える。
ディレクトリ指定すると直下のファイルすべてが対象になるが、サブフォルダの中身まではやってくれない。

# cat /etc/logrotate.d/remotelog
/var/log/syslog/*/*/*.log {
    missingok
    notifempty
    daily
    compress
    rotate 30
    postrotate
        /bin/kill -HUP `cat /var/run/syslogd.pid 2> /dev/null` 2> /dev/null || true
    endscript
}

logrotate の確認

cron の処理を即時実行

# logrotate -d /etc/logrotate.d/remotelog

設定が間違っているとこんな感じのエラーになる。

 logrotate -d /etc/logrotate.d/remotelog
reading config file /etc/logrotate.d/remotelog
Allocating hash table for state file, size 15360 B

Handling 1 logs

rotating pattern: /var/log/syslog  after 1 days (30 rotations)
empty log files are not rotated, old logs are removed
No logs found. Rotation not needed.

強制的に圧縮を実行

# logrotate -f /etc/logrotate.d/remotelog