Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

/var (persistent variable system data)

The /var directory stores persistent variable system data.

/var/cache (cache)

Applications must be able to rebuild their /var/cache data from other sources, so erasing data here does not cause data loss. For example, DNF keeps its repository metadata cache under /var/cache/libdnf5 and rebuilds it on the next metadata refresh.

/var/lib (persistent system data)

System components store persistent, private data under /var/lib. In contrast to /var/cache, erasing data here causes data loss. For example, the RPM database lives in /var/lib/rpm, and the PostgreSQL database server stores database data in /var/lib/pgsql.

/var/log (persistent logs)

The /var/log directory holds persistent logs. Software should prefer the syslog(3) or sd_journal_print(3) API calls over writing log files directly. Read the systemd journal with journalctl; for more information, see the journalctl(1) man page. Applications that write their own log files under /var/log document their own rotation configuration.

/var/spool (queued data)

Persistent queued data, such as mail or printer queues.

/var/tmp (larger temporary files)

Although /tmp is a tmpfs file system, /var/tmp is a path on the root file system, and is the place for larger and longer-lived temporary files. A cleanup job removes files not recently accessed; to configure it, see the tmpfiles.d(5) and systemd-tmpfiles(8) man pages.

As with /tmp, prefer the $TMPDIR environment variable over the hardcoded path, use safe temporary file creation (see Using /tmp and /var/tmp safely on the systemd.io website), and set PrivateTmp= for systemd services.