Keep journal logs after reboot (persistent journal)

Create /var/log/journal and restart journald so boot logs are kept permanently and `journalctl --boot=-1` can inspect the previous boot.

LinuxlogssystemdtroubleshootingMedium risk

Run `sudo mkdir -p /var/log/journal && sudo systemctl restart systemd-journald`; to revert, delete the directory and restart journald.

01Command

Command

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

02What it does

Many distros ship a volatile journal stored only in /run/log/journal, so all logs disappear at shutdown — making it impossible to investigate why the last boot crashed. The journal switches to persistent storage automatically when /var/log/journal exists. Disk use is then capped by SystemMaxUse (default: 10% of the filesystem) rather than growing unbounded.

03Risk

RiskMedium risk

Requirementssystemd; root required

!Warning: On small disks or eMMC/SD storage, persistent logs add some write wear; limit size with `sudo mkdir` plus SystemMaxUse in /etc/systemd/journald.conf if that concerns you.

04Undo

Undo

$ sudo rm -rf /var/log/journal && sudo systemctl restart systemd-journald

05Sources

journald.conf(5) — journal daemon configuration
Debian · community · 2026-09-17
Evidence: describes Storage=persistent keeping the journal in /var/log/journal
journald.conf(5) — journal storage configuration
Arch Linux · community · 2026-09-17
Evidence: Storage=persistent keeps logs in /var/log/journal across boots

Last verified: 2026-09-18 · Category: System & Settings

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