Package org.snmp4j.agent
Class BaseAgent
java.lang.Object
org.snmp4j.agent.BaseAgent
- All Implemented Interfaces:
Runnable
- Direct Known Subclasses:
SnapshotAgent
,TestAgent
The
BaseAgent
abstract class defines a framework for writing
SNMP agents using the SNMP4J-Agent API. To implement your own SNMP agent,
extend this class and implement the abstract methods defined by BaseAgent.
The hook methods do not need any specific implementation. They only provide
a defined mechanism to customize your agent.- Version:
- 1.0
- Author:
- Frank Fock
-
Field Summary
Modifier and TypeFieldDescriptionprotected CommandProcessor
protected int
protected EngineBootsCounterFile
protected String
protected org.snmp4j.smi.OctetString
protected DefaultMOPersistenceProvider
protected ProxyForwarder
protected org.snmp4j.MessageDispatcherImpl
protected org.snmp4j.mp.MPv3
protected NotificationOriginator
protected DefaultMOServer
protected org.snmp4j.Snmp
protected Snmp4jConfigMib
protected Snmp4jLogMib
protected SnmpCommunityMIB
protected SnmpFrameworkMIB
protected SnmpMpdMib
protected SnmpNotificationMIB
protected SnmpProxyMIB
protected SnmpTargetMIB
protected SNMPv2MIB
static final int
static final int
static final int
static final int
static final int
protected org.snmp4j.smi.OctetString
protected org.snmp4j.smi.OID
protected org.snmp4j.smi.Integer32
protected org.snmp4j.TransportMapping<? extends org.snmp4j.smi.Address>[]
protected org.snmp4j.security.USM
protected UsmMIB
protected VacmMIB
-
Constructor Summary
ModifierConstructorDescriptionprotected
BaseAgent
(File bootCounterFile, File configFile, CommandProcessor commandProcessor) Creates a base agent with boot-counter, config file, and a CommandProcessor for processing SNMP requests.protected
Creates a base agent with aDefaultMOServer
asMOServer
. -
Method Summary
Modifier and TypeMethodDescriptionprotected abstract void
addCommunities
(SnmpCommunityMIB communityMIB) Adds community to security name mappings needed for SNMPv1 and SNMPv2c.protected abstract void
addNotificationTargets
(SnmpTargetMIB targetMIB, SnmpNotificationMIB notificationMIB) Adds initial notification targets and filters.protected void
Adds a shutdown hook that saves the internal config into the config file when a SIGTERM (Ctrl-C) is terminating the agent.protected abstract void
addUsmUser
(org.snmp4j.security.USM usm) Adds all the necessary initial users to the USM.protected abstract void
Adds initial VACM configuration.protected void
Finishes initialization of the agent by connecting server and command processor, setting up USM, VACM, notification targets, and finally sending a coldStart notification to configured targets.getAgent()
int
Returns the agent's state.protected org.snmp4j.smi.OctetString
getContext
(MOGroup mibGroup) This method can be overwritten by a subagent to specify the contexts each MIB module (group) will be registered to.org.snmp4j.smi.OctetString
Returns the default context - which is the context that is used by the base agent to register its MIB objects.protected int
Reads the engine boots counter from the corresponding input stream (file).org.snmp4j.mp.MPv3
getMPv3()
org.snmp4j.Snmp
org.snmp4j.smi.OctetString
org.snmp4j.smi.OID
org.snmp4j.smi.Integer32
org.snmp4j.security.USM
getUsm()
void
init()
Initialize transport mappings, message dispatcher, basic MIB modules, proxy forwarder, VACM and USM security, and custom MIB modules and objects provided by sub-classes.protected void
protected void
Initializes the message dispatcher (MessageDispatcherImpl
) with the transport mappings.protected void
protected void
Initializes the transport mappings (ports) to be used by the agent.void
loadConfig
(int importMode) Loads the configuration using the specified import mode from the set config file.protected abstract void
Register additional managed objects at the agent's server.protected void
Register the basic MIB modules at the agent'sMOServer
.void
run()
Starts the agent by let it listen on the configured SNMP agent ports (transpot mappings).void
Save the current (serializable) managed object configuration into the config file.protected void
void
setAgent
(CommandProcessor agent) void
setBootCounterFile
(File bootCounterFile) void
setConfigFile
(File configFile) void
setDefaultContext
(org.snmp4j.smi.OctetString defaultContext) Sets the default context for this base agent.void
setDefaultProxyForwarder
(ProxyForwarder defaultProxyForwarder) void
setSysDescr
(org.snmp4j.smi.OctetString sysDescr) void
setSysOID
(org.snmp4j.smi.OID sysOID) void
setSysServices
(org.snmp4j.smi.Integer32 sysServices) protected void
Creates and registers the default proxy forwarder application (ProxyForwarderImpl
).void
stop()
Stops the agent by closing the SNMP session and associated transport mappings.protected abstract void
Unregister additional managed objects from the agent's server.protected void
Unregister the basic MIB modules from the agent'sMOServer
.protected int
Updates the engine boots counter and returns the actual value.protected void
updateSession
(org.snmp4j.Session session) Updates all objects with a new session instance.
-
Field Details
-
STATE_CREATED
public static final int STATE_CREATED- See Also:
-
STATE_INIT_STARTED
public static final int STATE_INIT_STARTED- See Also:
-
STATE_INIT_FINISHED
public static final int STATE_INIT_FINISHED- See Also:
-
STATE_RUNNING
public static final int STATE_RUNNING- See Also:
-
STATE_STOPPED
public static final int STATE_STOPPED- See Also:
-
snmpv2MIB
-
snmpMpdMib
-
snmpFrameworkMIB
-
snmpTargetMIB
-
snmpNotificationMIB
-
snmpProxyMIB
-
snmpCommunityMIB
-
snmp4jLogMIB
-
snmp4jConfigMIB
-
usmMIB
-
vacmMIB
-
server
-
session
protected org.snmp4j.Snmp session -
transportMappings
protected org.snmp4j.TransportMapping<? extends org.snmp4j.smi.Address>[] transportMappings -
dispatcher
protected org.snmp4j.MessageDispatcherImpl dispatcher -
agent
-
mpv3
protected org.snmp4j.mp.MPv3 mpv3 -
usm
protected org.snmp4j.security.USM usm -
bootCounterFile
-
notificationOriginator
-
defaultProxyForwarder
-
sysDescr
protected org.snmp4j.smi.OctetString sysDescr -
sysOID
protected org.snmp4j.smi.OID sysOID -
sysServices
protected org.snmp4j.smi.Integer32 sysServices -
agentState
protected int agentState -
defaultContext
protected org.snmp4j.smi.OctetString defaultContext -
defaultPersistenceProvider
-
configFileURI
-
-
Constructor Details
-
BaseAgent
Creates a base agent with aDefaultMOServer
asMOServer
. To use a different server implementation, modify theserver
member after construction.- Parameters:
configURI
- the URI of the config file holding persistent data for this agent. If persistent data is not used then set this parameter tonull
.
-
BaseAgent
Creates a base agent with boot-counter, config file, and a CommandProcessor for processing SNMP requests.- Parameters:
bootCounterFile
- a file with serialized boot-counter information (read/write). If the file does not exist it is created on shutdown of the agent.configFile
- a file with serialized configuration information (read/write). If the file does not exist it is created on shutdown of the agent.commandProcessor
- theCommandProcessor
instance that handles the SNMP requests.
-
-
Method Details
-
init
Initialize transport mappings, message dispatcher, basic MIB modules, proxy forwarder, VACM and USM security, and custom MIB modules and objects provided by sub-classes.- Throws:
IOException
- if initialization fails because transport initialization fails.
-
initConfigMIB
protected void initConfigMIB() -
getContext
This method can be overwritten by a subagent to specify the contexts each MIB module (group) will be registered to.- Parameters:
mibGroup
- a group ofManagedObject
s (i.e., a MIB module).- Returns:
- the context for which the module should be registered.
- Since:
- 1.1
-
registerSnmpMIBs
protected void registerSnmpMIBs()Register the basic MIB modules at the agent'sMOServer
. -
unregisterSnmpMIBs
protected void unregisterSnmpMIBs()Unregister the basic MIB modules from the agent'sMOServer
. -
registerManagedObjects
protected abstract void registerManagedObjects()Register additional managed objects at the agent's server. -
unregisterManagedObjects
protected abstract void unregisterManagedObjects()Unregister additional managed objects from the agent's server. -
setupDefaultProxyForwarder
protected void setupDefaultProxyForwarder()Creates and registers the default proxy forwarder application (ProxyForwarderImpl
). -
loadConfig
public void loadConfig(int importMode) Loads the configuration using the specified import mode from the set config file.- Parameters:
importMode
- one of the import modes defined byImportModes
.
-
saveConfig
public void saveConfig()Save the current (serializable) managed object configuration into the config file. -
addShutdownHook
protected void addShutdownHook()Adds a shutdown hook that saves the internal config into the config file when a SIGTERM (Ctrl-C) is terminating the agent. -
finishInit
protected void finishInit()Finishes initialization of the agent by connecting server and command processor, setting up USM, VACM, notification targets, and finally sending a coldStart notification to configured targets. -
sendColdStartNotification
protected void sendColdStartNotification() -
run
public void run()Starts the agent by let it listen on the configured SNMP agent ports (transpot mappings). -
stop
public void stop()Stops the agent by closing the SNMP session and associated transport mappings.- Since:
- 1.1
-
initMessageDispatcher
protected void initMessageDispatcher()Initializes the message dispatcher (MessageDispatcherImpl
) with the transport mappings. -
initSnmpSession
protected void initSnmpSession() -
updateSession
protected void updateSession(org.snmp4j.Session session) Updates all objects with a new session instance. This method must be overwritten, if non-default SNMP MIB instances are created by a subclass.- Parameters:
session
- a SNMP Session instance.
-
updateEngineBoots
protected int updateEngineBoots()Updates the engine boots counter and returns the actual value.- Returns:
- the actual boots counter value.
-
getEngineBoots
protected int getEngineBoots()Reads the engine boots counter from the corresponding input stream (file).- Returns:
- the boots counter value read or zero if it could not be read.
-
addUsmUser
protected abstract void addUsmUser(org.snmp4j.security.USM usm) Adds all the necessary initial users to the USM.- Parameters:
usm
- the USM instance used by this agent.
-
addNotificationTargets
protected abstract void addNotificationTargets(SnmpTargetMIB targetMIB, SnmpNotificationMIB notificationMIB) Adds initial notification targets and filters.- Parameters:
targetMIB
- the SnmpTargetMIB holding the target configuration.notificationMIB
- the SnmpNotificationMIB holding the notification (filter) configuration.
-
addViews
Adds initial VACM configuration.- Parameters:
vacmMIB
- the VacmMIB holding the agent's view configuration.
-
addCommunities
Adds community to security name mappings needed for SNMPv1 and SNMPv2c.- Parameters:
communityMIB
- the SnmpCommunityMIB holding coexistence configuration for community based security models.
-
initTransportMappings
Initializes the transport mappings (ports) to be used by the agent.- Throws:
IOException
- if an IO exception occurs while initializing the default transport mapping on all local IP addresses on port 161.
-
getNotificationOriginator
-
setDefaultProxyForwarder
-
setSysDescr
public void setSysDescr(org.snmp4j.smi.OctetString sysDescr) -
setSysOID
public void setSysOID(org.snmp4j.smi.OID sysOID) -
setSysServices
public void setSysServices(org.snmp4j.smi.Integer32 sysServices) -
setAgent
-
setBootCounterFile
-
setConfigFile
-
setDefaultContext
public void setDefaultContext(org.snmp4j.smi.OctetString defaultContext) Sets the default context for this base agent. By setting this value before any MIB modules have been registered at the internal server, the context for which the registration is performed can be changed. The default context isnull
which causes MIB objects to be virtually registered for all contexts.- Parameters:
defaultContext
- the context for default MIB objects.- Since:
- 1.1
-
getDefaultProxyForwarder
-
getSysDescr
public org.snmp4j.smi.OctetString getSysDescr() -
getSysOID
public org.snmp4j.smi.OID getSysOID() -
getSysServices
public org.snmp4j.smi.Integer32 getSysServices() -
getAgent
-
getBootCounterFile
-
getConfigFile
-
getSnmp4jConfigMIB
-
getSnmp4jLogMIB
-
getSnmpCommunityMIB
-
getSnmpFrameworkMIB
-
getSnmpNotificationMIB
-
getSnmpProxyMIB
-
getSnmpTargetMIB
-
getSnmpv2MIB
-
getSnmpMpdMib
-
getUsmMIB
-
getVacmMIB
-
getSession
public org.snmp4j.Snmp getSession() -
getServer
-
getMPv3
public org.snmp4j.mp.MPv3 getMPv3() -
getUsm
public org.snmp4j.security.USM getUsm() -
getAgentState
public int getAgentState()Returns the agent's state.- Returns:
- one of the state's starting from
STATE_CREATED
toSTATE_RUNNING
. - Since:
- 1.1
-
getDefaultContext
public org.snmp4j.smi.OctetString getDefaultContext()Returns the default context - which is the context that is used by the base agent to register its MIB objects. By default it isnull
which causes the objects to be registered virtually for all contexts. In that case, subagents for example my not register their own objects under the same subtree(s) in any context. To allow subagents to register their own instances of those MIB modules, an emptyOctetString
should be used as default context instead.- Returns:
null
or anOctetString
(normally the empty string) denoting the context used for registering default MIBs.- Since:
- 1.1
-