The
daemon server the internet SNMP (Simple Network Management Protocol).
It is intended to serve only the absolute basic MIBs and implement all other
MIBs through loadable modules.
In this way the
can be used in unexpected ways.
The options are as follows:
-d
This option is used for debugging
and causes it not to daemonize itself.
-h
This option prints a short usage message.
-c file
Use
file
as configuration file instead of the standard one.
-D options
Debugging options are specified with a
-o
flag followed by a comma separated string of options.
The following options are available.
dump
This option causes all sent and received PDUs to be dumped to the terminal.
events
This causes the debugging level of the event library (see
eventlib(3))
to be set to 10.
trace = level
This option causes the snmp library trace flag to be set to the specified
value.
The value can be specified in the usual C-syntax for numbers.
-I paths
This option specifies a colon separated list of directories to search for
configuration include files.
The default is
/etc:/usr/etc/:/usr/local/etc
These paths are only searched for include specified within <> parentheses.
-l prefix
The
prefix
is used as the default basename for the pid and the configuration files.
-m variable [= value
]
Define a configuration variable.
-p file
Specify an alternate pid file instead of the default one.
CONFIGURATION
The
reads its configuration from either the default or the user specified
configuration file.
The configuration file consists of the following types of lines:
variable assignments
section separators
include directives
MIB variable assignments
If a line is too long it can be continued on the next line by ending it with
a backslash.
Empty lines and lines in which the first non-blank character is a
``#''
sign are ignored.
All MIB variable assignments of the entire configuration (including nested
configuration files) are handled as one transaction, i.e., as if they arrived
in a single SET PDU.
Any failure during the initial configuration read causes
to exit.
A failure during the configuration read caused by a module load
causes the loading of the module to fail.
The configuration is read during initialization of
,
when a module is loaded and when
receives a SIGHUP.
VARIABLE ASSIGNMENTS
Variable assignments can take one of two forms:
variable := string
variable ?= string
The string reaches from the first non-blank character after the
equal sign until the first new line or
``#''
character.
In the first case
the string is assigned to the variable unconditionally, in the second case the
variable is only assigned if it does not exist yet.
Variable names must begin with a letter or underscore and contain only letters,
digits or underscores.
SECTION SEPARATORS
The configuration consists of named sections.
The MIB variable assignments in the section named
``snmpd''
are executed only during initial setup or when
receives a SIGHUP.
All other sections are executed when either a module
with the same name as the section is loaded or
receives a SIGHUP and that module is already loaded.
The default section at the start of the configuration is
``snmpd''
One can switch to another section with the syntax
%secname
Where
secname
is the name of the section.
The same
secname
can be used in more than one place in the configuration.
All of these parts are collected into one section.
INCLUDE DIRECTIVES
Another configuration file can be included into the current one with the
include directive that takes one of two forms:
.include "file"
.include <"file">
The first form causes the file to be searched in the current directory, the
second form causes the file to be searched in the directories specified in
the system include path.
Nesting depth is only restricted by available memory.
MIB VARIABLE ASSIGNMENTS
A MIB variable is assigned with the syntax
oid [ suboids ] = value
oid
is the name of the variable to be set.
Only the last component of the entire name is used here.
If the variable is a scalar, the index (.0) is automatically
appended and need not to be specified.
If the variable is a table column, the index
(suboids
)
must be specified.
The index consist of elements each separated from the
previous one by a dot.
Elements may be either numbers, strings or hostnames
enclosed in [] brackets.
If the element is a number it is appended
to the current oid.
If the element is a string, its length and the
ASCII
code of each of its characters are appended to the current oid.
If the
element is a hostname, the IP address of the host is looked up and the four
elements of the IP address are appended to the oid.
The value of the assignment may be either empty, a string or a number.
If a string starts with a letter or an underscore and consists only of
letters, digits, underscores and minus signs, it can be written without
quotes.
In all other cases the string must be enclosed in double quotes.
SUBSTITUTIONS
A variable substitution is written as
$(variable)
where
variable
is the name of the variable to substitute.
Using an undefined variable is considered an error.
FILES
/etc/ Ao prefix Ac .config
Default configuration file, where the default
Aq prefix
is
``snmpd''
/var/run/ Ao prefix Ac .pid
Default pid file.
/etc:/usr/etc/:/usr/local/etc
This is the default search path for system include files.
/usr/share/snmp/mibs/FOKUS-MIB.txt
/usr/share/snmp/mibs/BEGEMOT-MIB.txt
/usr/share/snmp/mibs/BEGEMOT-SNMPD.txt
The definitions for the MIBs implemented in the daemon.
/etc/hosts.allow, /etc/hosts.deny
Access controls that should be enforced by TCP wrappers should be defined here.
Further details are described in
hosts_access5.