> A "bad" daemon might not print anything to stdout when invoked (which goes to dmesg) but regardless, this whole comment just reeks of someone who hasn't actually dealt with systems before 2014.
The daemons never print to dmesg -- they may print to syslog, but not all do. The only daemon that I know of that prints to dmesg is systemd :)
To be specific, let's do a simple example. Here is an actual sysvinit file, /etc/init.d/hwclock.sh . It contains:
if /sbin/hwclock --rtc=/dev/$HCTOSYS_DEVICE --hctosys $HWCLOCKPARS $BADYEAR; then
# Announce the local time.
verbose_log_action_msg "System Clock set to: `date $UTC`"
else
log_warning_msg "Unable to set System Clock to: `date $UTC`"
fi
This version has been around since at least 1998 [0]. Old school enough for you?
So here is a simple question: let's say my hwclock chip/driver is unreliable and it did not work on startup for some reason, so that "hwclock" call is failing. My kernel timezone is not set right, the clock is off, and the system does log_warning_msg to warn you about it. How do I find out about this warning?
To make your job simpler, here is how the how this function is defined on my system:
if log_use_fancy_output; then
YELLOW=`$TPUT setaf 3`
NORMAL=`$TPUT op`
echo " $YELLOW*$NORMAL $@" || true
else
echo " * $@" || true
fi
Note no dmesg here, no syslog, no other loggers. You can say "bootlog", but it has been broken every time I tried to use it.
Now, nothing is impossible! I can hack this script so it writes to a temporary file. I can re-execute it again, and hope it fails again. But this gets old, you know? I can spend all day debugging early boot shell, but I did it for a long time already, so now I just want to type "systemctl show --failed", see all the failed services, fix it quickly, and move on to more interesting stuff.
> A "bad" daemon might not print anything to stdout when invoked (which goes to dmesg) but regardless, this whole comment just reeks of someone who hasn't actually dealt with systems before 2014.
The daemons never print to dmesg -- they may print to syslog, but not all do. The only daemon that I know of that prints to dmesg is systemd :)
To be specific, let's do a simple example. Here is an actual sysvinit file, /etc/init.d/hwclock.sh . It contains:
This version has been around since at least 1998 [0]. Old school enough for you?So here is a simple question: let's say my hwclock chip/driver is unreliable and it did not work on startup for some reason, so that "hwclock" call is failing. My kernel timezone is not set right, the clock is off, and the system does log_warning_msg to warn you about it. How do I find out about this warning?
To make your job simpler, here is how the how this function is defined on my system:
Note no dmesg here, no syslog, no other loggers. You can say "bootlog", but it has been broken every time I tried to use it.Now, nothing is impossible! I can hack this script so it writes to a temporary file. I can re-execute it again, and hope it fails again. But this gets old, you know? I can spend all day debugging early boot shell, but I did it for a long time already, so now I just want to type "systemctl show --failed", see all the failed services, fix it quickly, and move on to more interesting stuff.
[0] https://www.mail-archive.com/debian-bugs-dist@lists.debian.o...