1SNMPTRAPD.CONF(5) Net-SNMP SNMPTRAPD.CONF(5)
2
6 snmptrapd.conf - configuration file for the Net-SNMP notification
7 receiver
8
10 The Net-SNMP notification receiver (trap daemon) uses one or more con‐
11 figuration files to control its operation and how incoming traps (and
12 INFORM requests) should be processed. This file (snmptrapd.conf) can
13 be located in one of several locations, as described in the snmp_con‐
14 fig(5) manual page.
15
17 Previously, snmptrapd would accept all incoming notifications, and log
18 them automatically (even if no explicit configuration was provided).
19 Starting with release 5.3, access control checks will be applied to
20 incoming notifications. If snmptrapd is run without a suitable configu‐
21 ration file (or equivalent access control settings), then such traps
22 WILL NOT be processed. See the section ACCESS CONTROL for more
23 details.
24 As with the agent configuration, the snmptrapd.conf directives can be
26 divided into four distinct groups.
27
29 snmpTrapdAddr [<transport-specifier>:]<transport-address>[,...]
30 defines a list of listening addresses, on which to receive
31 incoming SNMP notifications. See the section LISTENING
32 ADDRESSES in the snmpd(8) manual page for more information about
33 the format of listening addresses.
34 The default behaviour is to listen on UDP port 162 on all IPv4
36 interfaces.
37 doNotRetainNotificationLogs yes
39 disables support for the NOTIFICATION-LOG-MIB. Normally the
40 snmptrapd program keeps a record of the traps received, which
41 can be retrieved by querying the nlmLogTable and nlmLogvari‐
42 ableTable tables. This directive can be used to suppress this
43 behaviour.
44 See the snmptrapd(8) manual page and the NOTIFICATION-LOG-MIB
46 for details.
47 doNotLogTraps yes
49 disables the logging of notifications altogether. This is use‐
50 ful if the snmptrapd application should only run traphandle
51 hooks and should not log traps to any location.
52 doNotFork yes
54 do not fork from the calling shell.
55 pidFile PATH
57 defines a file in which to store the process ID of the notifica‐
58 tion receiver. By default, this ID is not saved.
59
61 Starting with release 5.3, it is necessary to explicitly specify who is
62 authorised to send traps and informs to the notification receiver (and
63 what types of processing these are allowed to trigger). This uses an
64 extension of the VACM model, used in the main SNMP agent.
65 There are currently three types of processing that can be specified:
67 log log the details of the notification - either in a speci‐
69 fied file, to standard output (or stderr), or via syslog
70 (or similar).
71 execute
73 pass the details of the trap to a specified handler pro‐
74 gram, including embedded perl.
75 net forward the trap to another notification receiver.
77 In the following directives, TYPES will be a (comma-separated) list of
79 one or more of these tokens. Most commonly, this will typically be
80 log,execute,net to cover any style of processing for a particular cate‐
81 gory of notification. But it is perfectly possible (even desirable) to
82 limit certain notification sources to selected processing only.
83 authCommunity TYPES COMMUNITY [SOURCE [OID | -v VIEW ]]
85 authorises traps (and SNMPv2c INFORM requests) with the speci‐
86 fied community to trigger the types of processing listed. By
87 default, this will allow any notification using this community
88 to be processed. The SOURCE field can be used to specify that
89 the configuration should only apply to notifications received
90 from particular sources - see snmpd.conf(5) for more details.
91 authUser TYPES [-s MODEL] USER [LEVEL [OID | -v VIEW ]]
93 authorises SNMPv3 notifications with the specified user to trig‐
94 ger the types of processing listed. By default, this will
95 accept authenticated requests. (authNoPriv or authPriv). The
96 LEVEL field can be used to allow unauthenticated notifications
97 (noauth), or to require encryption (priv), just as for the SNMP
98 agent.
99 With both of these directives, the OID (or -v VIEW) field can be
101 used to retrict this configuration to the processing of particu‐
102 lar notifications.
103 Note: Unlike the VACM processing described in RFC 3415, this
105 view is only matched against the snmpTrapOID value of the
106 incoming notification. It is not applied to the payload
107 varbinds held within that notification.
108 authGroup TYPES [-s MODEL] GROUP [LEVEL [OID | -v VIEW ]]
110 authAccess TYPES [-s MODEL] GROUP VIEW [LEVEL [CONTEXT]]
112 setAccess GROUP CONTEXT MODEL LEVEL PREFIX VIEW TYPES
114 authorise notifications in the specified GROUP (configured using
115 the group directive) to trigger the types of processing listed.
116 See snmpd.conf(5) for more details.
117 createUser [-e ENGINEID] username
119 (MD5|SHA|SHA-512|SHA-384|SHA-256|SHA-224) authpassphrase [DES|AES]
120 See the snmpd.conf(5) manual page for a description of how to
121 create SNMPv3 users. This is roughly the same, but the file
122 name changes to snmptrapd.conf from snmpd.conf.
123 disableAuthorization yes
125 will disable the above access control checks, and revert to the
126 previous behaviour of accepting all incoming notifications.
127
129 format1 FORMAT
130 format2 FORMAT
132 specify the format used to display SNMPv1 TRAPs and SNMPv2 noti‐
133 fications respectively. Note that SNMPv2c and SNMPv3 both use
134 the same SNMPv2 PDU format.
135 format DESTINATION FORMAT
137 specify the format used for different destinations. DESTINATION
138 is one of: print, print1, print2, syslog, syslog1, syslog2, exe‐
139 cute, execute1, execute2. print1 is used for printing SNMPv1
140 traps, print2 is for SNMPv2. print is used for both versions.
141 syslog is similarly used when sending traps to syslog, and exe‐
142 cute used when sending traps to a program such as traptoe‐
143 mail(1).
144 The default formats are
146 format print1 %.4y-%.2m-%.2l %.2h:%.2j:%.2k %B [%b] (via %A
147 [%a]): %N\n\t%W Trap (%q) Uptime: %#T\n%v\n
148 format print2 %.4y-%.2m-%.2l %.2h:%.2j:%.2k %B [%b]:\n%v\n
149 format syslog1 %a: %W Trap (%q) Uptime: %#T%#v\n
150 format syslog2 %B [%b]: Trap %#v\n
151 format execute %B\n%b\n%V\n%v\n
152 See snmptrapd(8) for the layout characters available.
154 ignoreAuthFailure yes
156 instructs the receiver to ignore authenticationFailure traps.
157 Note: This currently only affects the logging of such notifica‐
159 tions. authenticationFailure traps will still be passed
160 to trap handler scripts, and forwarded to other notifica‐
161 tion receivers. This behaviour should not be relied on,
162 as it is likely to change in future versions.
163 logOption string
165 specifies where notifications should be logged - to standard
166 output, standard error, a specified file or via syslog. See the
167 section LOGGING OPTIONS in the snmpcmd(1) manual page for
168 details.
169 outputOption string
171 specifies various characteristics of how OIDs and other values
172 should be displayed. See the section OUTPUT OPTIONS in the snm‐
173 pcmd(1) manual page for details.
174
176 There are two configuration variables that work together to control
177 when queued traps are logged to the MySQL database. A non-zero value
178 must be specified for sqlSaveInterval to enable MySQL logging.
179 sqlMaxQueue max
181 specifies the maximum number of traps to queue before a forced
182 flush to the MySQL database.
183 sqlSaveInterval seconds
185 specified the number of seconds between periodic queue flushes.
186 A value of 0 for will disable MySQL logging.
187
189 As well as logging incoming notifications, they can also be forwarded
190 on to another notification receiver, or passed to an external program
191 for specialised processing.
192 traphandle OID|default PROGRAM [ARGS ...]
194 invokes the specified program (with the given arguments) when‐
195 ever a notification is received that matches the OID token. For
196 SNMPv2c and SNMPv3 notifications, this token will be compared
197 against the snmpTrapOID value taken from the notification. For
198 SNMPv1 traps, the generic and specific trap values and the
199 enterprise OID will be converted into the equivalent OID (fol‐
200 lowing RFC 2576).
201 Typically, the OID token will be the name (or numeric OID) of a
203 NOTIFICATION-TYPE object, and the specified program will be
204 invoked for notifications that match this OID exactly. However
205 this token also supports a simple form of wildcard suffixing.
206 By appending the character ´*' to the OID token, the correspond‐
207 ing program will be invoked for any notification based within
208 subtree rooted at the specified OID. For example, an OID token
209 of .1.3.6.1.4.1* would match any enterprise specific notifica‐
210 tion (including the specified OID itself). An OID token of
211 .1.3.6.1.4.1.* would would work in much the same way, but would
212 not match this exact OID - just notifications that lay strictly
213 below this root. Note that this syntax does not support full
214 regular expressions or wildcards - an OID token of the form
215 oid.*.subids is not valid.
216 If the OID field is the token default then the program will be
218 invoked for any notification not matching another (OID specific)
219 traphandle entry.
220 Details of the notification are fed to the program via its standard
222 input. Note that this will always use the SNMPv2-style notification
223 format, with SNMPv1 traps being converted as per RFC 2576, before being
224 passed to the program. The input format is, if you use the default set
225 by the "format execute %B\n%b\n%V\n%v\n", one entry per line:
226 HOSTNAME
228 The name of the host that sent the notification, as
229 determined by gethostbyaddr(3).
230 ADDRESS
232 The transport address, like
233 "[UDP: [172.16.10.12]:23456->[10.150.0.8]]"
234 VARBINDS
236 A list of variable bindings describing the contents of
237 the notification, one per line. The first token on each
238 line (up until a space) is the OID of the varind, and the
239 remainder of the line is its value. The format of both
240 of these are controlled by the outputOption directive (or
241 similar configuration).
242 The first OID should always be SNMPv2-MIB::sysUpTime.0,
244 and the second should be SNMPv2-MIB::snmpTrapOID.0. The
245 remaining lines will contain the payload varbind list.
246 For SNMPv1 traps, the final OID will be
247 SNMPv2-MIB::snmpTrapEnterprise.0.
248 Example:
250 A traptoemail script has been included in the Net-SNMP
251 package that can be used within a traphandle directive:
252 traphandle default /usr/bin/perl /usr/bin/traptoemail -s
254 mysmtp.somewhere.com -f admin@somewhere.com me@some‐
255 where.com
256 forward OID|default DESTINATION
258 forwards notifications that match the specified OID to another
259 receiver listening on DESTINATION. The interpretation of OID
260 (and default) is the same as for the traphandle directive).
261 See the section LISTENING ADDRESSES in the snmpd(8) manual page
263 for more information about the format of listening addresses.
264 addForwarderInfo 1|yes|true|0|no|false
266 Each time a trap is forwarded, add an OID with the IP address of
268 the system from which the trap has been received. The following
269 OID is added: .1.3.6.1.6.3.18.1.3.x (SNMP-COMMUNITY-
270 MIB::snmpTrapAddress.x) where x is the lowest index >= 0 that
271 does not yet occur in the trap payload. The end recipient (i.e.
272 the monitoring system) can determine the IPv4 address of the
273 original sender by looking for the varbind with OID snmpTrapAd‐
274 dress.0. If that OID is not populated it means that the trap has
275 been sent directly or in other words that it has not been for‐
276 warded.
277
279 o The daemon blocks while executing the traphandle commands.
280 (This should be fixed in the future with an appropriate signal
281 catch and wait() combination).
282 o All directives listed with a value of "yes" actually accept a
284 range of boolean values. These will accept any of 1, yes or
285 true to enable the corresponding behaviour, or any of 0, no or
286 false to disable it. The default in each case is for the fea‐
287 ture to be turned off, so these directives are typically only
288 used to enable the appropriate behaviour.
289
291 /etc/snmp/snmptrapd.conf
292
294 snmp_config(5), snmptrapd(8), syslog(8), traptoemail(1), variables(5),
295 netsnmp_config_api(3).
296V5.9 13 Mar 2014 SNMPTRAPD.CONF(5)