Re: [systemd-devel] How to log to journald using fifo?
On Wed, 13.04.16 23:43, Samuel Williams (space.ship.travel...@gmail.com) wrote: > I guess what I'm proposing is not a specific workaround but a way for > legacy software which can only log to a file to get it's data into > journald. There is plenty of software like that, unfortunately. It's a > pragmatic option. > > In this specific case, I'm referring to Nginx in daemon mode, which closes > /dev/stderr as far as I can tell, and then spawns passenger, which can only > log to a file. There is no way to hook up passenger to /dev/stderr. Hmm, this might work: "touch /tmp/ && mount --bind /proc/self/fd/2 /tmp/" That will bind mount your fd 2 to /tmp/, and then you can reopen it from there later... (Didn't try that this actually works, but I think this should pin the open fd. YMMV.) Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] How to log to journald using fifo?
On Wed, Apr 13, 2016 at 2:43 PM, Samuel Williams < space.ship.travel...@gmail.com> wrote: > I guess what I'm proposing is not a specific workaround but a way for > legacy software which can only log to a file to get it's data into > journald. There is plenty of software like that, unfortunately. It's a > pragmatic option. > > In this specific case, I'm referring to Nginx in daemon mode, which closes > /dev/stderr as far as I can tell, and then spawns passenger, which can only > log to a file. There is no way to hook up passenger to /dev/stderr. > > The proposed service allows anyone to set up a fifo for logging in this > situation, it's very trivial and easy to set up, but I suspect there is > more than just one person with this issue. > If you're going to run a service anyway, could you use e.g. rsyslog's imfile → omjournal modules? -- Mantas Mikulėnas ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] How to log to journald using fifo?
I guess what I'm proposing is not a specific workaround but a way for legacy software which can only log to a file to get it's data into journald. There is plenty of software like that, unfortunately. It's a pragmatic option. In this specific case, I'm referring to Nginx in daemon mode, which closes /dev/stderr as far as I can tell, and then spawns passenger, which can only log to a file. There is no way to hook up passenger to /dev/stderr. The proposed service allows anyone to set up a fifo for logging in this situation, it's very trivial and easy to set up, but I suspect there is more than just one person with this issue. On 12 April 2016 at 02:21, Lennart Poettering wrote: > On Sun, 10.04.16 22:57, Samuel Williams (space.ship.travel...@gmail.com) > wrote: > > > Hello, > > > > > > I've been trying to figure out the best way to support legacy > applications > > that don't support syslog for logging. The best we can do, I think, is to > > use fifo and have another process read the fifo to journald. > > Note that on systemd everything logged out stdout or stderr ends up in > the journal anyway. And you can specify /dev/stderr or /proc/self/fd/2 > as path referring to stderr on Linux generally, if you need. > > > Finally, if this is a good approach, is this method worth putting into > > systemd/journald as a standard service? If so, how do I submit a PR or > > where to begin? > > Specific work-arounds around other, unrelated pieces of software are > not really what we we'd like to add to systemd directly. Sorry. > > Lennart > > -- > Lennart Poettering, Red Hat > ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] How to log to journald using fifo?
On Sun, 10.04.16 22:57, Samuel Williams (space.ship.travel...@gmail.com) wrote: > Hello, > > > I've been trying to figure out the best way to support legacy applications > that don't support syslog for logging. The best we can do, I think, is to > use fifo and have another process read the fifo to journald. Note that on systemd everything logged out stdout or stderr ends up in the journal anyway. And you can specify /dev/stderr or /proc/self/fd/2 as path referring to stderr on Linux generally, if you need. > Finally, if this is a good approach, is this method worth putting into > systemd/journald as a standard service? If so, how do I submit a PR or > where to begin? Specific work-arounds around other, unrelated pieces of software are not really what we we'd like to add to systemd directly. Sorry. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] How to log to journald using fifo?
I would like to write to /dev/stderr and tried that but it didn’t work. I think it’s something to do with the way it works internally (nginx + phusion passenger). > On 11/04/2016, at 12:43 AM, Mantas Mikulėnas wrote: > > On Sun, Apr 10, 2016 at 1:57 PM, Samuel Williams > mailto:space.ship.travel...@gmail.com>> > wrote: > Hello, > > I've been trying to figure out the best way to support legacy applications > that don't support syslog for logging. The best we can do, I think, is to use > fifo and have another process read the fifo to journald. > > I made the following unit journald-fifo@.service > > [Unit] > Description=A fifo for logging to journald > AssertPathExists=/var/log/%i.fifo > > [Service] > Type=simple > ExecStart=/bin/sh -c 'while true; do systemd-cat -t %i < /var/log/%i.fifo; > done' > Nice=5 > > [Install] > WantedBy=multi-user.target > > I was wondering is this a good approach? Is there a better way? (of course, > we'd like to fix the original software to work better). > > If the software can log to stdout/stderr, just use that. If not, make it > write logs to "/dev/stderr". Either way, systemd will log service stdout > automatically. > > -- > Mantas Mikulėnas mailto:graw...@gmail.com>> ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] How to log to journald using fifo?
On Sun, Apr 10, 2016 at 1:57 PM, Samuel Williams < space.ship.travel...@gmail.com> wrote: > Hello, > > > I've been trying to figure out the best way to support legacy applications > that don't support syslog for logging. The best we can do, I think, is to > use fifo and have another process read the fifo to journald. > > > I made the following unit journald-fifo@.service > > > [Unit] > > Description=A fifo for logging to journald > > AssertPathExists=/var/log/%i.fifo > > > [Service] > > Type=simple > > ExecStart=/bin/sh -c 'while true; do systemd-cat -t %i < /var/log/%i.fifo; > done' > > Nice=5 > > > [Install] > > WantedBy=multi-user.target > > I was wondering is this a good approach? Is there a better way? (of > course, we'd like to fix the original software to work better). > If the software can log to stdout/stderr, just use that. If not, make it write logs to "/dev/stderr". Either way, systemd will log service stdout automatically. -- Mantas Mikulėnas ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] How to log to journald using fifo?
Hello, I've been trying to figure out the best way to support legacy applications that don't support syslog for logging. The best we can do, I think, is to use fifo and have another process read the fifo to journald. I made the following unit journald-fifo@.service [Unit] Description=A fifo for logging to journald AssertPathExists=/var/log/%i.fifo [Service] Type=simple ExecStart=/bin/sh -c 'while true; do systemd-cat -t %i < /var/log/%i.fifo; done' Nice=5 [Install] WantedBy=multi-user.target I was wondering is this a good approach? Is there a better way? (of course, we'd like to fix the original software to work better). Finally, if this is a good approach, is this method worth putting into systemd/journald as a standard service? If so, how do I submit a PR or where to begin? Kind regards, Samuel ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
