日志保留策略
journalctl command
mkdir -p /var/log/journal
systemctl restart systemd-journald
journalctl --verify
ls -l /var/log/journal/
cat /etc/systemd/journald.conf
vim /etc/systemd/journald.conf
SystemMaxUse=2G
MaxRetentionSec=1month
echo "SystemMaxUse=2G" >> /etc/systemd/journald.conf
echo "MaxRetentionSec=1month" >> /etc/systemd/journald.conf
systemctl restart systemd-journald
journalctl -n 10 #last 10
journalctl -f #Auto reflash
journalctl -k #kernel
journalctl -u #service
journalctl --since today #time