Get-SNMP Cmdlet

Parameters   Output Objects   Config Settings  

The Get-SNMP component is used to query SNMP agents.

Syntax

Get-SNMP [parameters]

Remarks

The GET-SNMP cmdlet implements a standard SNMP Manager as specified in the SNMP RFCs. The cmdlet supports SNMP v1, v2c, and v3 through the Version parameter.

The cmdlet provides encoding/decoding, transport capabilities, and OID resolution, allowing for SNMP agents to be monitored directly from Powershell.

SNMP Get, GetNext, Walk and GetBulk are all supported.

SNMPv3 USM security is enabled by setting properties such as User and AuthenticationPassword. SNMPv3 encryption is enabled by setting EncryptionPassword.

Automatic translation from Node labels to OIDs is integrated in the cmdlet, allowing for a seamless integration with MIB files of different vendors.

The cmdlets support pipeline input for some of their parameters. Prebuilding an object and piping it to the cmdlet is very useful, but should be used with caution to prevent security conflicts. Steps have been taken to decrease the risk of a possibly accidental pipe to the cmdlet, for instance, the Credential parameter cannot be piped to the cmdlet and must be specified manually.

# snmp broadcast for agent information get-snmp -agent 255.255.255.255 -oid 1.3.6.1.2.1.1.1.0 -translate # perform a get-next request get-snmp 10.0.1.11 sysDescr.0 -next:$true # send a get-bulk request get-snmp -agent 10.0.1.11 -oid sysName.0, sysDescr.0 -bulk 5 -NonRepeaters 1

Parameter List

---

The following is the full list of the parameters of the cmdlet with short descriptions. Click on the links for further details.

LogFile	The location of a file to which debug information is written.
Agent	The address of the SNMP agent.
AuthenticationPassword	The password to use for SNMPv3 authentication.
AuthenticationProtocol	The authentication protocol used.
Bulk	Indicates the number of maxRepetitions used to send a GetBulkRequest.
Community	The community string used to authenticate SNMP packets.
Config	Specifies one or more configuration settings.
EncryptionAlgorithm	The encryption algorithm used for the request.
EncryptionPassword	The password to use for SNMPv3 privacy encryption.
LocalIP	The IP address of the local interface to use.
LogFile	The location of a file to which debug information is written.
Mib	Extra mib files to use for the Label to OID translation and vice versa.
Next	Send a GetNext request for the OID .
NonRepeaters	Count of variables not to be repeated.
OID	The OID to use for this request.
Port	The UDP port where the remote SNMP agent is listening.
Timeout	The maximum time allowed for the operation.
Translate	Resolve OIDs to labels in the response for the SNMP request.
User	The username to use for authentication.
Version	The version of SNMP to use for the request.
Walk	Does an SNMP walk starting with the oid specified by OID .

Output Objects

---

The following is the full list of the output objects returned by the cmdlet with short descriptions. Click on the links for further details.

OID	Returned from the SNMP operation.

Config Settings

---

The following is a list of config settings for the cmdlet with short descriptions. Click on the links for further details.

HexMACAddress	Determines if MAC addresses are automatically hex encoded.
UseScalarInstance	Whether to automatically use the OID for scalar object instances.
BuildInfo	Information about the product's build.
CodePage	The system code page used for Unicode to Multibyte translations.
LicenseInfo	Information about the current license.
MaskSensitive	Whether sensitive data is masked in log messages.
UseInternalSecurityAPI	Tells the component whether or not to use the system security libraries or an internal implementation.

LogFile Parameter (Get-SNMP Cmdlet)

The location of a file to which debug information is written.

Syntax

Get-SNMP -LogFile string

Remarks

When specified, the cmdlet will log debug information to the file. If the file exists, the information will be appended.

Default Value

null

Agent Property (Get-SNMP Cmdlet)

The address of the SNMP agent.

Syntax

Get-SNMP -Agent string

Remarks

The address or host name of the SNMP agent with which to communicate.

Default Value

""

Parameter Position

0

Parameter Alias

SNMPAgent

This is a required parameter.

AuthenticationPassword Property (Get-SNMP Cmdlet)

The password to use for SNMPv3 authentication.

Syntax

Get-SNMP -AuthenticationPassword string

Remarks

Every time EncryptionPassword or AuthenticationPassword are set, a localized key is computed automatically, and cached internally.

Default Value

""

Parameter Alias

AuthPassword

AuthenticationProtocol Property (Get-SNMP Cmdlet)

The authentication protocol used.

Syntax

Get-SNMP -AuthenticationProtocol string

Remarks

AuthenticationProtocol is used to specify the authentication protocol used when sending a secure trap.

Possible authentication protocol types are:

• MD5 (default)
• SHA

Default Value

1

Parameter Alias

AuthProtocol

Bulk Property (Get-SNMP Cmdlet)

Indicates the number of maxRepetitions used to send a GetBulkRequest.

Syntax

Get-SNMP -Bulk int

Remarks

Specifies the number of lexicographic successors to be returned. The NonRepeaters flag can also be set to the number of non repeaters for the GetBulk request.

Default Value

0

Community Property (Get-SNMP Cmdlet)

The community string used to authenticate SNMP packets.

Syntax

Get-SNMP -Community string

Remarks

Must match the community name that is specified on the agent.

Typical values are "public" or "private".

This parameter is used for all SNMP packets sent by the cmdlet.

Default Value

"public"

Config Property (Get-SNMP Cmdlet)

Specifies one or more configuration settings.

Syntax

Get-SNMP -Config string[]

Remarks

The Config parameter takes one or more name-value pairs that represent the name of the configuration setting and value, i.e.: -config "Name=Value"

Default Value

null

EncryptionAlgorithm Property (Get-SNMP Cmdlet)

The encryption algorithm used for the request.

Syntax

Get-SNMP -EncryptionAlgorithm string

Remarks

EncryptionAlgorithm is used to specify the encryption algorithm used when sending a secure request.

Possible encryption algorithm types are:

• DES (default)
• AES
• 3DES
• AES192
• AES256

Default Value

1

Parameter Alias

EncAlgorithm

EncryptionPassword Property (Get-SNMP Cmdlet)

The password to use for SNMPv3 privacy encryption.

Syntax

Get-SNMP -EncryptionPassword string

Remarks

Every time EncryptionPassword or AuthenticationPassword are set, a localized key is computed automatically, and cached internally.

Default Value

""

Parameter Alias

EncPassword

LocalIP Property (Get-SNMP Cmdlet)

The IP address of the local interface to use.

Syntax

Get-SNMP -LocalIP string

Remarks

This parameter is useful when the cmdlet is running on a machine that has more than one network interface (each with its own IP address and network access privileges).

Default Value

""

Parameter Alias

LocalAddress

LogFile Property (Get-SNMP Cmdlet)

The location of a file to which debug information is written.

Syntax

Get-SNMP -LogFile string

Remarks

When specified, the cmdlet will log debug information to the file. If the file exists, the information will be appended.

Default Value

""

Mib Property (Get-SNMP Cmdlet)

Extra mib files to use for the Label to OID translation and vice versa.

Syntax

Get-SNMP -Mib string[]

Remarks

The cmdlet will automatically pick up the mib files located in the "mibs" folder of the NetCmdlets module location. By default this will be "%UserProfile%\Documents\WindowsPowerShell\Modules\NetCmdlets\mibs".

By default some standard mib files are provided with the installation.

Default Value

null

Next Property (Get-SNMP Cmdlet)

Send a GetNext request for the OID .

Syntax

Get-SNMP -Next SwitchParameter

Remarks

If doing multiple GetNext requests a bulk or a walk would be a better alternative depending on the functionality that you want to achieve.

Default Value

false

NonRepeaters Property (Get-SNMP Cmdlet)

Count of variables not to be repeated.

Syntax

Get-SNMP -NonRepeaters int

Remarks

NonRepeaters specifies the number of variables for which a single lexicographic successor is to be returned.

Default Value

0

OID Property (Get-SNMP Cmdlet)

The OID to use for this request.

Syntax

Get-SNMP -OID string[]

Remarks

The OID can be a label or an actual OID, such as sysDescr.0 or 1.3.6.1.2.1.1.1.0.

Default Value

null

Parameter Position

1

Parameter Alias

Label

This is a required parameter.

Port Property (Get-SNMP Cmdlet)

The UDP port where the remote SNMP agent is listening.

Syntax

Get-SNMP -Port int

Remarks

Port specifies a service port on the remote host to which to connect.

A valid port number (a value between 1 and 65535) is required for the connection to take place.

Default Value

161

Parameter Alias

AgentPort

Timeout Property (Get-SNMP Cmdlet)

The maximum time allowed for the operation.

Syntax

Get-SNMP -Timeout int

Remarks

After the specified interval in seconds, the cmdlet will throw a Timeout error if the operation is not completed.

Default Value

10

Translate Property (Get-SNMP Cmdlet)

Resolve OIDs to labels in the response for the SNMP request.

Syntax

Get-SNMP -Translate SwitchParameter

Remarks

If the Translate switch is set, the cmdlet will attempt to resolve the textual syntax for any OID returned from the agent(s). If the Mib parameter is set, the cmdlet will use the specified Mib, the cmdlet will automatically pick up the mib files located in the MIBS folder of the NetCmdlets installation directory.

If the Translate switch is not set, or the OID cannot be matched, the numerical syntax will be returned.

Default Value

false

Parameter Alias

Resolve

User Property (Get-SNMP Cmdlet)

The username to use for authentication.

Syntax

Get-SNMP -User string

Remarks

When setting User you could also set EncryptionPassword and/or AuthenticationPassword depending on whether the desired behavior is authentication, encryption or both.

Default Value

""

Version Property (Get-SNMP Cmdlet)

The version of SNMP to use for the request.

Syntax

Get-SNMP -Version int

Remarks

The default version used is 2.

Default Value

2

Walk Property (Get-SNMP Cmdlet)

Does an SNMP walk starting with the oid specified by OID .

Syntax

Get-SNMP -Walk SwitchParameter

Remarks

A walk will traverse all OIDs in the OID table that are lexographically greater than OID. The result is given through a series of OID objects.

Default Value

false

OID Output Object (Get-SNMP Cmdlet)

Returned from the SNMP operation.

Syntax

Object OID {
   string Host;
   string OID;
   string OIDValue;
   byte[] OIDValueB;
   string OIDType;
   int ErrorIndex;
   int ErrorStatus;
   string ErrorDescription;
}

Remarks

For each OID in every response received by the cmdlet an OID object will be returned.

Host contains the host address that the response was returned from.

OID contains the OID name for the response. If the Translate switch is set, the cmdlet will attempt to resolve the textual syntax for the OID.

OIDValue contains the value for the OID.

OIDValueB contains the value for the OID expressed as a byte array.

OIDType contains the type of OID received.

Possible object type values include:

• Integer
• OctetString
• Null
• ObjectID
• IPAddress
• Counter32
• Gauge32
• TimeTicks
• Opaque
• NSAP
• Counter64
• UnsignedInteger32

The cmdlet also supports the following artificial object values used to designate error conditions:

ErrorIndex contains the index of the variable which caused the error.

ErrorStatus contains the status code.

The following is a list of valid SNMP status code values:

The ErrorIndex parameter indicates the index of the first variable (object) that caused an error. The default value is 0.

Variable indexes start with 0. ErrorIndex has no meaning when ErrorStatus is 0 (no error).

ErrorDescription provides a textual description of the error.

Config Settings (Get-SNMP Cmdlet)

The cmdlet accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the cmdlet, access to these internal properties is provided through the Config method.

Get-SNMP Config Settings

Base Config Settings