I was using logger command to see if the logs goes to journal, and it does, it goes both in /var/log/messages (owned by syslog) and journal, how is it happening? Is it because journal listens to /dev/log ?
The following is from systemd-journald.socket
[Socket]
ListenStream=/run/systemd/journal/stdout
ListenDatagram=/run/systemd/journal/socket
ListenDatagram=/dev/log
ListenStream=/run/systemd/journal/stdout
ListenDatagram=/run/systemd/journal/socket
ListenDatagram=/dev/log
Also can we edit 'systemd-journald.socket ' so as to not listen to /dev/log ? Just for seeing its behaviour.
I tried by commenting out and removing 'ListenDatagram=/dev/log' and restarted the socket and journal service, but the logger log is still displayed in journal
Nishant
On Fri, 20 Aug 2021 at 16:43, Mantas Mikulėnas <grawity@xxxxxxxxx> wrote:
On Fri, Aug 20, 2021 at 2:11 PM Mantas Mikulėnas <grawity@xxxxxxxxx> wrote:On Fri, Aug 20, 2021 at 2:10 PM Nishant Nayan <nayan.nishant2000@xxxxxxxxx> wrote:Regarding the below point :c) The service prints to stdout/stderr, but systemd attaches the service's stdout/stderr to a pipe which is read by journald (using sd_journal_stream_fd(3) from libsystemd). See [Service] StandardOutput= in systemd.service(5).I did not see StandardOutput field in [Service] sections of a service file, for example sshd.service, but its logs are visible in journalctl.Is it by default piped to journal and we need to explicitly mention it (StandardOutput=) only when we want to redirect it somewhere else?StandardOutput=journal is the default setting.And, actually, sshd doesn't write its messages to stdout anyway – it uses syslog() via /dev/log; most daemons do.--Mantas Mikulėnas
