systemd-id128 — Generate and print sd-128 identifiers
systemd-id128 [OPTIONS...] new
systemd-id128 [OPTIONS...] machine-id
systemd-id128 [OPTIONS...] boot-id
systemd-id128 [OPTIONS...] invocation-id
id128 may be used to conveniently print sd-id128(3) UUIDs. What identifier is printed depends on the specific verb.
With new, a new random identifier will be generated.
With machine-id, the identifier of the current machine will be printed. See machine-id(5).
With boot-id, the identifier of the current boot will be printed.
Both machine-id and boot-id may be combined
--app-specific= switch to
generate application-specific IDs. See
for the discussion when this is useful.
With invocation-id, the identifier of the current service invocation will be printed. This is available in systemd services. See systemd.exec(5).
With show, well-known UUIDs are printed. When no arguments are specified, all known UUIDs are shown. When arguments are specified, they must be the names or values of one or more known UUIDs, which are then printed.
The following options are understood:
Generate output as programming language snippets.
With this option, an identifier that is the result of hashing the
app-id and the machine identifier will be
app-id argument must be a valid sd-id128 string
identifying the application.
Generate output as an UUID formatted in the "canonical representation", with five groups of digits separated by hyphens. See the wikipedia for more discussion.
On success, 0 is returned, a non-zero failure code otherwise.