sys logging does not work out of the box

[luisgarciaalanis]

BUG: images are missing rsyslog service preventing applications from using the Linux system level logger.

The following app returns: Unix syslog delivery error

package main

import (
	"fmt"
	"log"
	"log/syslog"
)

func main() {
	logwriter, err := syslog.New(syslog.LOG_NOTICE, "myprog")
	if err != nil {
		fmt.Println(err.Error())
	}
	log.SetOutput(logwriter)
}

Should the images be including this basic system feature?

[tianon]

This "basic system feature" is actually a daemon just like any other (it just happens to commonly place its Unix socket under /dev instead of /run), so installing the package for it wouldn't actually do anything. If you need syslog, I'd recommend running it in a separate container and using TCP or a Unix socket in a shared volume to write to it.

[luisgarciaalanis]

I tried apt-get installing rsyslog and it does fix the issue, I just wondered if it was worth including this functionality on the base containers. If not I will create a custom image and publish it.

[tianon]

It might fix the issue temporarily by creating a dummy /dev/log in that one container, but it doesn't actually fix the issue in the sense that /dev/log will exist in a new container nor will it make /dev/log magically log anywhere. On your host, /dev/log (the standard syslog socket) is just a standard Unix socket (which happens to commonly live under /dev for legacy reasons) to a daemon running on the host. In order for "syslog" to work the way you expect it to inside a container, you need that same /dev/log Unix socket provided by something (either a bind-mount to the host so it can communicate directly to the host's syslog server or using something like s6 or supervisord to run a separate syslog server inside your container alongside your application).