📜 Logs & journalctl

Advanced log analysis using systemd journal.

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🔧 Basic Usage

journalctl
journalctl -u <service>
journalctl -xe

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🧩 Filtering

journalctl -p err
journalctl --since "1 hour ago"
journalctl -u nginx --since today

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🔍 Live Logs

journalctl -f

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🧱 Persistent Logs

Enable:

sudo mkdir -p /var/log/journal
sudo systemd-tmpfiles --create --prefix /var/log/journal
sudo systemctl restart systemd-journald

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🚨 Debugging Boot Issues

journalctl -b -1