Смотрим
man journald.conf
ForwardToSyslog=, ForwardToKMsg=, ForwardToConsole=, ForwardToWall=
Control whether log messages received by the journal daemon shall be forwarded to a traditional syslog
daemon, to the kernel log buffer (kmsg), to the system console, or sent as wall messages to all logged-in
users. These options take boolean arguments. If forwarding to syslog is enabled but nothing reads messages
from the socket, forwarding to syslog has no effect. By default, only forwarding to wall is enabled. These
settings may be overridden at boot time with the kernel command line options
"systemd.journald.forward_to_syslog=", "systemd.journald.forward_to_kmsg=",
"systemd.journald.forward_to_console=", and "systemd.journald.forward_to_wall=". When forwarding to the
console, the TTY to log to can be changed with TTYPath=, described below.
MaxLevelStore=, MaxLevelSyslog=, MaxLevelKMsg=, MaxLevelConsole=, MaxLevelWall=
Controls the maximum log level of messages that are stored on disk, forwarded to syslog, kmsg, the console or
wall (if that is enabled, see above). As argument, takes one of "emerg", "alert", "crit", "err", "warning",
"notice", "info", "debug", or integer values in the range of 0–7 (corresponding to the same levels). Messages
equal or below the log level specified are stored/forwarded, messages above are dropped. Defaults to "debug"
for MaxLevelStore= and MaxLevelSyslog=, to ensure that the all messages are written to disk and forwarded to
syslog. Defaults to "notice" for MaxLevelKMsg=, "info" for MaxLevelConsole=, and "emerg" for MaxLevelWall=.
TTYPath=
Change the console TTY to use if ForwardToConsole=yes is used. Defaults to /dev/console.