Moved the documentation of the console log level into its own section
This commit is contained in:
parent
2ee736c8cf
commit
c6675cb832
117
klogd.8
117
klogd.8
@ -39,12 +39,6 @@ messages.
|
||||
.TP
|
||||
.BI "\-c " n
|
||||
Sets the default log level of console messages to \fIn\fR.
|
||||
This should nowardays be configured with the
|
||||
.BR sysctl (8)
|
||||
program, e.g. via
|
||||
.BI "sysctl kernel.printk=" n
|
||||
or via
|
||||
.IR /etc/sysctl.conf .
|
||||
.TP
|
||||
.B "\-d"
|
||||
Enable debugging mode. This will generate \fBLOTS\fR of output to
|
||||
@ -138,55 +132,6 @@ the appropriate priority level to the syslog message. If file output
|
||||
(\fB-f\fR) is used the prioritization sequence is left pre\-pended to the
|
||||
kernel message.
|
||||
|
||||
The
|
||||
.B klogd
|
||||
daemon also allows the ability to alter the presentation of
|
||||
kernel messages to the system console. Consequent with the
|
||||
prioritization of kernel messages was the inclusion of default
|
||||
messaging levels for the kernel. In a stock kernel the the default
|
||||
console log level is set to 7. Any messages with a priority level
|
||||
numerically lower than 7 (higher priority) appear on the console.
|
||||
|
||||
Messages of priority level 7 are considered to be 'debug' messages and
|
||||
will thus not appear on the console. Many administrators,
|
||||
particularly in a multi\-user environment, prefer that all kernel
|
||||
messages be handled by klogd and either directed to a file or to
|
||||
the syslogd daemon. This prevents 'nuisance' messages such as line
|
||||
printer out of paper or disk change detected from cluttering the
|
||||
console.
|
||||
|
||||
When
|
||||
.B \-c
|
||||
is given on the commandline the
|
||||
.B klogd
|
||||
daemon will execute a system call to inhibit all kernel messages from
|
||||
being displayed on the console. Former versions always issued this
|
||||
system call and defaulted to all kernel messages except for panics.
|
||||
This is handled differently nowardays so
|
||||
.B klogd
|
||||
doesn't need to set this value anymore. The
|
||||
argument given to the \fB\-c\fR switch specifies the priority level of
|
||||
messages which will be directed to the console. Note that messages of
|
||||
a priority value LOWER than the indicated number will be directed to
|
||||
the console.
|
||||
.IP
|
||||
For example, to have the kernel display all messages with a
|
||||
priority level of 3
|
||||
.BR "" ( KERN_ERR )
|
||||
or more severe the following
|
||||
command would be executed:
|
||||
.IP
|
||||
.nf
|
||||
klogd \-c 4
|
||||
.fi
|
||||
.PP
|
||||
The definitions of the numeric values for kernel messages are given in
|
||||
the file
|
||||
.IR kernel.h " which can be found in the " /usr/include/linux
|
||||
directory if the kernel sources are installed. These values parallel
|
||||
the syslog priority values which are defined in the file
|
||||
.IR syslog.h " found in the " /usr/include/sys " sub\-directory."
|
||||
|
||||
The klogd daemon can also be used in a 'one\-shot' mode for reading the
|
||||
kernel message buffers. One shot mode is selected by specifying the
|
||||
\fB\-o\fR switch on the command line. Output will be directed to either the
|
||||
@ -349,6 +294,68 @@ whenever a module is inserted or removed from the kernel. Using this
|
||||
patch will insure that the symbol information maintained in klogd is
|
||||
always consistent with the current kernel state.
|
||||
.PP
|
||||
.SH CONSOLE LOG LEVEL
|
||||
The
|
||||
.B klogd
|
||||
daemon allows the ability to alter the presentation of
|
||||
kernel messages to the system console. Consequent with the
|
||||
prioritization of kernel messages was the inclusion of default
|
||||
messaging levels for the kernel. In a stock kernel the the default
|
||||
console log level is set to 7. Any messages with a priority level
|
||||
numerically lower than 7 (higher priority) appear on the console.
|
||||
|
||||
Messages of priority level 7 are considered to be 'debug' messages and
|
||||
will thus not appear on the console. Many administrators,
|
||||
particularly in a multi\-user environment, prefer that all kernel
|
||||
messages be handled by klogd and either directed to a file or to
|
||||
the syslogd daemon. This prevents 'nuisance' messages such as line
|
||||
printer out of paper or disk change detected from cluttering the
|
||||
console.
|
||||
|
||||
When
|
||||
.B \-c
|
||||
is given on the commandline the
|
||||
.B klogd
|
||||
daemon will execute a system call to inhibit all kernel messages from
|
||||
being displayed on the console. Former versions always issued this
|
||||
system call and defaulted to all kernel messages except for panics.
|
||||
This is handled differently nowardays so
|
||||
.B klogd
|
||||
doesn't need to set this value anymore. The
|
||||
argument given to the \fB\-c\fR switch specifies the priority level of
|
||||
messages which will be directed to the console. Note that messages of
|
||||
a priority value LOWER than the indicated number will be directed to
|
||||
the console.
|
||||
.IP
|
||||
For example, to have the kernel display all messages with a
|
||||
priority level of 3
|
||||
.BR "" ( KERN_ERR )
|
||||
or more severe the following
|
||||
command would be executed:
|
||||
.IP
|
||||
.nf
|
||||
klogd \-c 4
|
||||
.fi
|
||||
.PP
|
||||
The definitions of the numeric values for kernel messages are given in
|
||||
the file
|
||||
.IR kernel.h " which can be found in the " /usr/include/linux
|
||||
directory if the kernel sources are installed. These values parallel
|
||||
the syslog priority values which are defined in the file
|
||||
.IR syslog.h " found in the " /usr/include/sys " sub\-directory."
|
||||
|
||||
The console log level is nowardays usually configured with the
|
||||
.BR sysctl (8)
|
||||
program, directly or via its configuration file
|
||||
.IR /etc/sysctl.conf .
|
||||
In this file the following line
|
||||
.IP
|
||||
.nf
|
||||
kernel.printk = 4 4 1 7
|
||||
.fi
|
||||
.PP
|
||||
corresponds to the sampe setting above.
|
||||
|
||||
.SH SIGNAL HANDLING
|
||||
The
|
||||
.B klogd
|
||||
|
Loading…
x
Reference in New Issue
Block a user