SNMP

Since Camel 2.1

Both producer and consumer are supported

The SNMP component gives you the ability to poll SNMP capable devices or receiving traps

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-snmp</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

snmp://hostname[:port][?Options]

The component supports polling OID values from an SNMP enabled device and receiving traps.

Snmp Producer

It can also be used to request information using GET method.

The response body type is org.apache.camel.component.snmp.SnmpMessage

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example a component may have security settings, credentials for authentication, urls for network connection and so forth.

Some components only have a few options, and others may have many. Because components typically have pre configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.

Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.

Configuring Endpoint Options

Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.

Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL as a type safe way of configuring endpoints.

A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.

The following two sections lists all the options, firstly for the component followed by the endpoint.

Component Options

The SNMP component supports 3 options, which are listed below.

Name Description Default Type

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

autowiredEnabled (advanced)

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

boolean

Endpoint Options

The SNMP endpoint is configured using URI syntax:

snmp:host:port

with the following path and query parameters:

Path Parameters (2 parameters)

Name Description Default Type

host (common)

Required Hostname of the SNMP enabled device.

String

port (common)

Required Port number of the SNMP enabled device.

Integer

Query Parameters (36 parameters)

Name Description Default Type

oids (common)

Defines which values you are interested in. Please have a look at the Wikipedia to get a better understanding. You may provide a single OID or a coma separated list of OIDs. Example: oids=1.3.6.1.2.1.1.3.0,1.3.6.1.2.1.25.3.2.1.5.1,1.3.6.1.2.1.25.3.5.1.1.1,1.3.6.1.2.1.43.5.1.1.11.1.

OIDList

protocol (common)

Here you can select which protocol to use. You can use either udp or tcp.

Enum values:

  • tcp

  • udp

udp

String

retries (common)

Defines how often a retry is made before canceling the request.

2

int

snmpCommunity (common)

Sets the community octet string for the snmp request.

public

String

snmpContextEngineId (common)

Sets the context engine ID field of the scoped PDU.

String

snmpContextName (common)

Sets the context name field of this scoped PDU.

String

snmpVersion (common)

Sets the snmp version for the request. The value 0 means SNMPv1, 1 means SNMPv2c, and the value 3 means SNMPv3.

Enum values:

  • 0

  • 1

  • 3

0

int

timeout (common)

Sets the timeout value for the request in millis.

1500

int

type (common)

Which operation to perform such as poll, trap, etc.

Enum values:

  • TRAP

  • POLL

  • GET_NEXT

SnmpActionType

delay (consumer)

Sets update rate in seconds.

60000

long

sendEmptyMessageWhenIdle (consumer)

If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.

false

boolean

treeList (consumer)

Sets the flag whether the scoped PDU will be displayed as the list if it has child elements in its tree.

false

boolean

bridgeErrorHandler (consumer (advanced))

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

exceptionHandler (consumer (advanced))

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

ExceptionHandler

exchangePattern (consumer (advanced))

Sets the exchange pattern when the consumer creates an exchange.

Enum values:

  • InOnly

  • InOut

  • InOptionalOut

ExchangePattern

pollStrategy (consumer (advanced))

A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel.

PollingConsumerPollStrategy

lazyStartProducer (producer (advanced))

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

backoffErrorThreshold (scheduler)

The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.

int

backoffIdleThreshold (scheduler)

The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.

int

backoffMultiplier (scheduler)

To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured.

int

greedy (scheduler)

If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.

false

boolean

initialDelay (scheduler)

Milliseconds before the first poll starts.

1000

long

repeatCount (scheduler)

Specifies a maximum limit of number of fires. So if you set it to 1, the scheduler will only fire once. If you set it to 5, it will only fire five times. A value of zero or negative means fire forever.

0

long

runLoggingLevel (scheduler)

The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.

Enum values:

  • TRACE

  • DEBUG

  • INFO

  • WARN

  • ERROR

  • OFF

TRACE

LoggingLevel

scheduledExecutorService (scheduler)

Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool.

ScheduledExecutorService

scheduler (scheduler)

To use a cron scheduler from either camel-spring or camel-quartz component. Use value spring or quartz for built in scheduler.

none

Object

schedulerProperties (scheduler)

To configure additional properties when using a custom scheduler or any of the Quartz, Spring based scheduler.

Map

startScheduler (scheduler)

Whether the scheduler should be auto started.

true

boolean

timeUnit (scheduler)

Time unit for initialDelay and delay options.

Enum values:

  • NANOSECONDS

  • MICROSECONDS

  • MILLISECONDS

  • SECONDS

  • MINUTES

  • HOURS

  • DAYS

MILLISECONDS

TimeUnit

useFixedDelay (scheduler)

Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.

true

boolean

authenticationPassphrase (security)

The authentication passphrase. If not null, authenticationProtocol must also be not null. RFC3414 11.2 requires passphrases to have a minimum length of 8 bytes. If the length of authenticationPassphrase is less than 8 bytes an IllegalArgumentException is thrown.

String

authenticationProtocol (security)

Authentication protocol to use if security level is set to enable authentication The possible values are: MD5, SHA1.

Enum values:

  • MD5

  • SHA1

String

privacyPassphrase (security)

The privacy passphrase. If not null, privacyProtocol must also be not null. RFC3414 11.2 requires passphrases to have a minimum length of 8 bytes. If the length of authenticationPassphrase is less than 8 bytes an IllegalArgumentException is thrown.

String

privacyProtocol (security)

The privacy protocol ID to be associated with this user. If set to null, this user only supports unencrypted messages.

String

securityLevel (security)

Sets the security level for this target. The supplied security level must be supported by the security model dependent information associated with the security name set for this target. The value 1 means: No authentication and no encryption. Anyone can create and read messages with this security level The value 2 means: Authentication and no encryption. Only the one with the right authentication key can create messages with this security level, but anyone can read the contents of the message. The value 3 means: Authentication and encryption. Only the one with the right authentication key can create messages with this security level, and only the one with the right encryption/decryption key can read the contents of the message.

Enum values:

  • 1

  • 2

  • 3

3

int

securityName (security)

Sets the security name to be used with this target.

String

The result of a poll

Given the situation, that I poll for the following OIDs:

OIDs

1.3.6.1.2.1.1.3.0
1.3.6.1.2.1.25.3.2.1.5.1
1.3.6.1.2.1.25.3.5.1.1.1
1.3.6.1.2.1.43.5.1.1.11.1

The result will be the following:

Result of toString conversion

<?xml version="1.0" encoding="UTF-8"?>
<snmp>
  <entry>
    <oid>1.3.6.1.2.1.1.3.0</oid>
    <value>6 days, 21:14:28.00</value>
  </entry>
  <entry>
    <oid>1.3.6.1.2.1.25.3.2.1.5.1</oid>
    <value>2</value>
  </entry>
  <entry>
    <oid>1.3.6.1.2.1.25.3.5.1.1.1</oid>
    <value>3</value>
  </entry>
  <entry>
    <oid>1.3.6.1.2.1.43.5.1.1.11.1</oid>
    <value>6</value>
  </entry>
  <entry>
    <oid>1.3.6.1.2.1.1.1.0</oid>
    <value>My Very Special Printer Of Brand Unknown</value>
  </entry>
</snmp>

As you maybe recognized there is one more result than requested…​.1.3.6.1.2.1.1.1.0.
This one is filled in by the device automatically in this special case. So it may absolutely happen, that you receive more than you requested…​be prepared.

OID starting with dot representation

.1.3.6.1.4.1.6527.3.1.2.21.2.1.50

As you may notice, default snmpVersion is 0 which means version1 in the endpoint if it is not set explicitly. Make sure you explicitly set snmpVersion which is not default value, of course in a case of where you are able to query SNMP tables with different versions. Other possible values are version2c and version3.

Examples

Polling a remote device:

snmp:192.168.178.23:161?protocol=udp&type=POLL&oids=1.3.6.1.2.1.1.5.0

Setting up a trap receiver (Note that no OID info is needed here!):

snmp:127.0.0.1:162?protocol=udp&type=TRAP

You can get the community of SNMP TRAP with message header 'securityName',
peer address of the SNMP TRAP with message header 'peerAddress'.

Routing example in Java: (converts the SNMP PDU to XML String)

from("snmp:192.168.178.23:161?protocol=udp&type=POLL&oids=1.3.6.1.2.1.1.5.0").
convertBodyTo(String.class).
to("activemq:snmp.states");