Tunnel Global Statistics Test

A tunnel is a virtual point-to-point link across a multipoint-access network, such as the Internet. Tunnels help you to create secure connections between remote users and a private corporate network via the internet. In a sense, a tunnel emulates a WAN link. A tunneling protocol:

  • encapsulates other protocols
  • sets up a point-to-point link

When you initiate communication or send data over VPN network via the HP Router, the Tunneling protocol(s) used by the VPN network (like PPTP, L2TP, IPSec etc.) wraps up the data packets into another data packet and encrypts the package that is to be sent through the tunnel. At the receiver’s end, the tunneling device/protocol deciphers the package and then strips the wrapped data packet to read and access the original message and reveal the source of packet and other classified information. This way, secure communication is possible with the tunnels. If the traffic through the tunnels are too high or if a tunnel is not available, then, data transmission and reception by the tunnels will take longer than usual which will inturn affect the performance of the HP Router. To avoid such situation, administrators should constantly monitor the level of traffic flowing through the tunnels of the HP Router. The Tunnel Global Statistics helps administrators perform the task with ease!

This test reports the number of active tunnels created on the target HP Router and measures the level of traffic to and from the tunnels. Using this test, administrators can be proactively alerted to the discrepancies in the data and packet transmission and reception.

Target of the test : A HP Router

Agent deploying the test : An external agent

Outputs of the test : One set of results for the target HP Router being monitored.

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The IP address of the HP Router that is being monitored.

SNMPPort

The port at which the monitored target exposes its SNMP MIB; the default is 161.

SNMPVersion

By default, the eG agent supports SNMP version 1. Accordingly, the default selection in the SNMPversion list is v1. However, if a different SNMP framework is in use in your environment, say SNMP v2 or v3, then select the corresponding option from this list.

SNMPCommunity

The SNMP community name that the test uses to communicate with the router. This parameter is specific to SNMP v1 and v2 only. Therefore, if the SNMPVersion chosen is v3, then this parameter will not appear.

Username

This parameter appears only when v3 is selected as the SNMPVersion. SNMP version 3 (SNMPv3) is an extensible SNMP Framework which supplements the SNMPv2 Framework, by additionally supporting message security, access control, and remote SNMP configuration capabilities. To extract performance statistics from the MIB using the highly secure SNMP v3 protocol, the eG agent has to be configured with the required access privileges – in other words, the eG agent should connect to the MIB using the credentials of a user with access permissions to be MIB. Therefore, specify the name of such a user against this parameter. 

Context

This parameter appears only when v3 is selected as the SNMPVersion. An SNMP context is a collection of management information accessible by an SNMP entity. An item of management information may exist in more than one context and an SNMP entity potentially has access to many contexts. A context is identified by the SNMPEngineID value of the entity hosting the management information (also called a contextEngineID) and a context name that identifies the specific context (also called a contextName). If the Username provided is associated with a context name, then the eG agent will be able to poll the MIB and collect metrics only if it is configured with the context name as well. In such cases therefore, specify the context name of the Username in the Context text box.  By default, this parameter is set to none.

AuthPass

Specify the password that corresponds to the above-mentioned Username. This parameter once again appears only if the SNMPversion selected is v3.

Confirm Password

Confirm the AuthPass by retyping it here.

AuthType

This parameter too appears only if v3 is selected as the SNMPVersion. From the AuthType list box, choose the authentication algorithm using which SNMP v3 converts the specified Username and password into a 32-bit format to ensure security of SNMP transactions. You can choose between the following options:

  • MD5 – Message Digest Algorithm
  • SHA – Secure Hash Algorithm

EncryptFlag

This flag appears only when v3 is selected as the SNMPVersion. By default, the eG agent does not encrypt SNMP requests. Accordingly, the this flag is set to No by default. To ensure that SNMP requests sent by the eG agent are encrypted, select the Yes option. 

EncryptType

If this EncryptFlag is set to Yes, then you will have to mention the encryption type by selecting an option from the EncryptType list. SNMP v3 supports the following encryption types:

  • DES – Data Encryption Standard
  • AES – Advanced Encryption Standard

EncryptPassword

Specify the encryption password here.

Confirm Password

Confirm the encryption password by retyping it here.

Timeout

Specify the duration (in seconds) within which the SNMP query executed by this test should time out in this text box. The default is 10 seconds.

Data Over TCP

By default, in an IT environment, all data transmission occurs over UDP. Some environments however, may be specifically configured to offload a fraction of the data traffic – for instance, certain types of data traffic or traffic pertaining to specific components – to other protocols like TCP, so as to prevent UDP overloads. In such environments, you can instruct the eG agent to conduct the SNMP data traffic related to the monitored target over TCP (and not UDP). For this, set this flag to Yes. By default, this flag is set to No.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Active tunnels

Indicates the number of tunnels that are currently active via the managed router.

Number

There should atleast be one active tunnel at any point of time. If the value of this measure is 0, then this test will not report any other metrics.

Received data

Indicates the amount of data received through the tunnels by the managed router during the last measurement period.

MB

 

Received packets

Indicates the number of packets received through the tunnels by the managed router during the last measurement period.

Number

 

Received drop packets

Indicates the number of packets that were dropped while packets were being received during the last measurement period.

Number

Ideally, the value of this measure should be zero.

Transmitted data

Indicates the amount of data transmitted through the tunnels from the managed router during the last measurement period.

MB

 

Transmitted packets

Indicates the number of packets transmitted through the tunnels from the managed router during the last measurement period.

Number

 

Transmitted drop packets

Indicates the number of packets that were dropped while packets were being transmitted through the tunnels during the last measurement period.

Number

Ideally, the value of this measure should be zero.

Comparing the value of this measure with the Received drop packets measure will help administrators identify when exactly the packets dropped were at the maximum - during reception or transmission?