1SNMP_CONFIG(5) Net-SNMP SNMP_CONFIG(5)
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6 snmp_config - handling of Net-SNMP configuration files
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9 The Net-SNMP package uses various configuration files to configure its
10 applications. This manual page merely describes the overall nature of
11 them, so that the other manual pages don't have to.
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14 First off, there are numerous places that configuration files can be
15 found and read from. By default, the applications look for configura‐
16 tion files in the following 4 directories, in order: /etc/snmp,
17 /usr/share/snmp, /usr/lib(64)/snmp, and $HOME/.snmp. In each of these
18 directories, it looks for files snmp.conf, snmpd.conf and/or
19 snmptrapd.conf, as well as snmp.local.conf, snmpd.local.conf and/or
20 snmptrapd.local.conf. *.local.conf are always read last. In this man‐
21 ner, there are 8 default places a configuration file can exist for any
22 given configuration file type.
23 Additionally, the above default search path can be overridden by set‐
25 ting the environment variable SNMPCONFPATH to a colon-separated list of
26 directories to search for. The path for the persistent data should be
27 included when running applications that use persistent storage, such as
28 snmpd.
29 Applications will read persistent configuration files in the following
31 order of preference:
32 file in SNMP_PERSISTENT_FILE environment variable
34 directories in SNMPCONFPATH environment variable
36 directory defined by persistentDir snmp.conf variable
38 directory in SNMP_PERSISTENT_DIR environment variable
40 default /var/lib/net-snmp directory
42 Finally, applications will write persistent configuration files in the
44 following order of preference:
45 file in SNMP_PERSISTENT_FILE environment variable
47 directory defined by persistentDir snmp.conf variable
49 directory in SNMP_PERSISTENT_DIR environment variable
51 default /var/lib/net-snmp directory
53 Note: When using SNMP_PERSISTENT_FILE, the filename should match the
55 application name. For example, /var/net-snmp/snmpd.conf.
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58 Each application may use multiple configuration files, which will con‐
59 figure various different aspects of the application. For instance, the
60 SNMP agent (snmpd) knows how to understand configuration directives in
61 both the snmpd.conf and the snmp.conf files. In fact, most applica‐
62 tions understand how to read the contents of the snmp.conf files.
63 Note, however, that configuration directives understood in one file may
64 not be understood in another file. For further information, read the
65 associated manual page with each configuration file type. Also, most
66 of the applications support a -H switch on the command line that will
67 list the configuration files it will look for and the directives in
68 each one that it understands.
69 The snmp.conf configuration file is intended to be a application suite
71 wide configuration file that supports directives that are useful for
72 controlling the fundamental nature of all of the SNMP applications,
73 such as how they all manipulate and parse the textual SNMP MIB files.
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76 It's possible to switch in mid-file the configuration type that the
77 parser is supposed to be reading. Since that sentence doesn't make
78 much sense, lets give you an example: say that you wanted to turn on
79 packet dumping output for the agent by default, but you didn't want to
80 do that for the rest of the applications (ie, snmpget, snmpwalk, ...).
81 Normally to enable packet dumping in the configuration file you'd need
82 to put a line like:
83 dumpPacket true
85 into the snmp.conf file. But, this would turn it on for all of the
87 applications. So, instead, you can put the same line in the snmpd.conf
88 file so that it only applies to the snmpd daemon. However, you need to
89 tell the parser to expect this line. You do this by putting a special
90 type specification token inside a [] set. In other words, inside your
91 snmpd.conf file you could put the above snmp.conf directive by adding a
92 line like so:
93 [snmp] dumpPacket true
95 This tells the parser to parse the above line as if it were inside a
97 snmp.conf file instead of an snmpd.conf file. If you want to parse a
98 bunch of lines rather than just one then you can make the context
99 switch apply to the remainder of the file or until the next context
100 switch directive by putting the special token on a line by itself:
101 # make this file handle snmp.conf tokens:
103 [snmp]
104 dumpPacket true
105 logTimestamp true
106 # return to our original snmpd.conf tokens:
107 [snmpd]
108 rocommunity mypublic
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111 Any lines beginning with the character '#' in the configuration files
112 are treated as a comment and are not parsed.
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115 It is possible to include other configuration files for processing dur‐
116 ing normal configuration file processing.:
117 # include site specific config
119 includeFile site.conf
120 This will search every directory in the configuration path for files
122 named site.conf, and will process those files before returning to the
123 processing of the original file. Note that if '.conf' is omitted,
124 it will be appended. That is, all configuration files must end
125 in '.conf'.
126 # include a all *.conf files in a directory
128 includeDir /etc/snmp/config.d
129 This will search specified directory for all files with '.conf'
131 suffix and process them as if they were included using includeFile
132 directive. The configuration files are not processed in any particular
133 order.
134 The specified directory must be absolute directory path.
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138 Information about writing C code that makes use of this system in
139 either the agent's MIB modules or in applications can be found in the
140 read_config(3) manual page.
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143 snmpconf(1), read_config(3), snmp.conf(5), snmpd.conf(5)
1444th Berkeley Distribution 5 May 2005 SNMP_CONFIG(5)