Ubuntu24.04LTS で /var/log/messages にログを記録する

cat << 'EOF' > /etc/rsyslog.d/50-default.conf
#  Default rules for rsyslog.
#
#   For more information see rsyslog.conf(5) and /etc/rsyslog.conf

#
# First some standard log files.  Log by facility.
#
auth,authpriv.*   /var/log/auth.log
*.*;auth,authpriv.none  -/var/log/syslog
#cron.*    /var/log/cron.log
#daemon.*   -/var/log/daemon.log
kern.*    -/var/log/kern.log
#lpr.*    -/var/log/lpr.log
mail.*    -/var/log/mail.log
#user.*    -/var/log/user.log

#
# Logging for the mail system.  Split it up so that
# it is easy to write scripts to parse these files.
#
#mail.info   -/var/log/mail.info
#mail.warn   -/var/log/mail.warn
mail.err   /var/log/mail.err

#
# Some "catch-all" log files.
#
#*.=debug;\
# auth,authpriv.none;\
# news.none;mail.none -/var/log/debug
*.=info;*.=notice;*.=warn;\
 auth,authpriv.none;\
 cron,daemon.none;\
 mail,news.none  -/var/log/messages

#
# Emergencies are sent to everybody logged in.
#
*.emerg    :omusrmsg:*

#
# I like to have messages displayed on the console, but only on a virtual
# console I usually leave idle.
#
#daemon,mail.*;\
# news.=crit;news.=err;news.=notice;\
# *.=debug;*.=info;\
# *.=notice;*.=warn /dev/tty8
EOF

systemctl restart rsyslog.service

cat << 'EOF' > /etc/logrotate.d/syslog
/var/log/messages
{
 rotate 4
 weekly
 missingok
 notifempty
 compress
 delaycompress
 sharedscripts
 postrotate
  /usr/lib/rsyslog/rsyslog-rotate
 endscript
}
EOF

# logrotate -d /etc/logrotate.conf
warning: logrotate in debug mode does nothing except printing debug messages!  Consider using verbose mode (-v) instead if this is not what you want.

reading config file /etc/logrotate.conf
including /etc/logrotate.d
reading config file alternatives
reading config file apport
reading config file apt
reading config file bootlog
reading config file btmp
reading config file cloud-init
reading config file dpkg
reading config file rsyslog
reading config file syslog
reading config file ubuntu-pro-client
reading config file ufw
reading config file unattended-upgrades
reading config file wtmp
Reading state from file: /var/lib/logrotate/status
state file /var/lib/logrotate/status does not exist
Allocating hash table for state file, size 64 entries

Handling 14 logs

rotating pattern: /var/log/alternatives.log  monthly (12 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/alternatives.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/apport.log  after 1 days (7 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/apport.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/apt/term.log  monthly (12 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/apt/term.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/apt/history.log  monthly (12 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/apt/history.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/boot.log
 after 1 days (7 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/boot.log
  log /var/log/boot.log does not exist -- skipping
Creating new state
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/btmp  monthly (1 rotations)
empty log files are rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/btmp
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/cloud-init*.log
 1048576 bytes (6 rotations)
empty log files are not rotated, old logs are removed
considering log /var/log/cloud-init-output.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log size is below the 'size' threshold)
considering log /var/log/cloud-init.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log size is below the 'size' threshold)

rotating pattern: /var/log/dpkg.log  monthly (12 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/dpkg.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/syslog
/var/log/mail.log
/var/log/kern.log
/var/log/auth.log
/var/log/user.log
/var/log/cron.log
 weekly (4 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/syslog
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
considering log /var/log/mail.log
  log /var/log/mail.log does not exist -- skipping
Creating new state
considering log /var/log/kern.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
considering log /var/log/auth.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
considering log /var/log/user.log
  log /var/log/user.log does not exist -- skipping
Creating new state
considering log /var/log/cron.log
  log /var/log/cron.log does not exist -- skipping
Creating new state
not running postrotate script, since no logs were rotated
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/messages
 weekly (4 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/messages
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
not running postrotate script, since no logs were rotated
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/ubuntu-advantage*.log  monthly (6 rotations)
empty log files are not rotated, old logs are removed
considering log /var/log/ubuntu-advantage*.log
  log /var/log/ubuntu-advantage*.log does not exist -- skipping
Creating new state

rotating pattern: /var/log/ufw.log
 weekly (4 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/ufw.log
  log /var/log/ufw.log does not exist -- skipping
Creating new state
not running postrotate script, since no logs were rotated
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/unattended-upgrades/unattended-upgrades.log
/var/log/unattended-upgrades/unattended-upgrades-dpkg.log
/var/log/unattended-upgrades/unattended-upgrades-shutdown.log
 monthly (6 rotations)
empty log files are not rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/unattended-upgrades/unattended-upgrades.log
  log /var/log/unattended-upgrades/unattended-upgrades.log does not exist -- skipping
Creating new state
considering log /var/log/unattended-upgrades/unattended-upgrades-dpkg.log
  log /var/log/unattended-upgrades/unattended-upgrades-dpkg.log does not exist -- skipping
Creating new state
considering log /var/log/unattended-upgrades/unattended-upgrades-shutdown.log
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

rotating pattern: /var/log/wtmp  monthly (1 rotations)
empty log files are rotated, only log files >= 1048576 bytes are rotated, old logs are removed
switching euid from 0 to 0 and egid from 0 to 4 (pid 1261)
considering log /var/log/wtmp
Creating new state
  Now: 2024-08-10 11:32
  Last rotated at 2024-08-10 11:00
  log does not need rotating (log has already been rotated)
switching euid from 0 to 0 and egid from 4 to 0 (pid 1261)

/var/log/syslog
/var/log/mail.log
/var/log/kern.log
/var/log/auth.log
/var/log/user.log
/var/log/cron.log
{
 rotate 4
 weekly
 missingok
 notifempty
 compress
 delaycompress
 sharedscripts
 postrotate
  /usr/lib/rsyslog/rsyslog-rotate
 endscript
}

#!/bin/sh

if [ -d /run/systemd/system ]; then
    systemctl kill -s HUP rsyslog.service
fi

#!/bin/sh

# skip in favour of systemd timer
if [ -d /run/systemd/system ]; then
    exit 0
fi

# this cronjob persists removals (but not purges)
if [ ! -x /usr/sbin/logrotate ]; then
    exit 0
fi

/usr/sbin/logrotate /etc/logrotate.conf
EXITVALUE=$?
if [ $EXITVALUE != 0 ]; then
    /usr/bin/logger -t logrotate "ALERT exited abnormally with [$EXITVALUE]"
fi
exit $EXITVALUE

/var/log/cron
/var/log/maillog
/var/log/messages
/var/log/secure
/var/log/spooler
{
    sharedscripts
    postrotate
        /bin/kill -HUP `cat /var/run/syslogd.pid 2> /dev/null` 2> /dev/null || true
    endscript
}