IB Subnet Manager Statistics Test

Subnet Manager (SM) is a centralized entity running in the InfiniBand switch. The SM discovers and configures all the InfiniBand fabric devices to enable traffic flow among those devices. The SM manages all operational characteristics of the InfiniBand network such as the following:

• Discovering the network topology

• Assigning a local identifier (LID) to all ports connected to the network

• Calculating and programming switch forwarding tables

• Programming Partition Key (PKEY) tables at HCAs and switches

• Programming QoS tables (Service Level to Virtual Lane mapping tables, and Virtual Lane arbitration tables)

• Monitoring changes in the fabric

The subnet manager uses Subnet Manager Agent (SMA) for communication inside and outside of the target InfiniBand switch. The real test of the efficiency of the subnet manager lies in its ability to communicate information across the components in the target switch using different kind of packets, for instance, Subnet Management Packets (SMP). If, for any reason, more number of packets are queued up and made to wait or response for the transmitted packets are not returned as expected, then the whole/part of information that the subnet manager is intended to communicate with the other components will not be delivered and thus, the communication will become unreliable. To avoid such incidents, administrators will have to monitor the packet transmission regularly. This can be easily done using the IB Subnet Manager Statistics test.

This test helps administrators to track the traffic of different packets handled by the subnet manager. Analyzing the statistics revealed by this test, administrators can easily determine how well the subnet manager processes requewhether the packet transmission handled by the subnet manager is reliable or not.

Target of the test : An InfiniBand Switch

Agent deploying the test : An external agent

Outputs of the test : One set of results for the InfiniBand Switch that is being monitored

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The IP address of the target switch 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 switch. 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.

EngineID

This parameter appears only when v3 is selected as the SNMPVersion. Sometimes, the test may not report metrics when AES192 or AES256 is chosen as the Encryption type. To ensure that the test report metrics consistently, administrators need to set this flag to Yes. By default, this parameter is set to No.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

SMP outstanding packets

Indicates the number of SMP packets that are queued up per second.

Packets/sec

All management traffic including the communication between the SMAs and the SM is handled using subnet management packets (SMP).

SMP onwire packets

Indicates the number of SMP packets that are currently in transmission per second.

Packets/sec

 

SMP Packets received

Indicates the number of SMP packets received per second since SM was started.

Packets/sec

 

SMP packets transmitted

Indicates the number of SMP packets transmitted per second since SM was started.

Packets/sec

 

SMP responseless packets transmitted

Indicates the number of responseless SMP packets transmitted per second.

Packets/sec

 

SMP unknown packets received

Indicates the number of unknown SMP packets transmitted per second.

Packets/sec

The SMP packets are regarded as unknown packet when they are transmitted with unknown attribute IDs and/or methods.

GMP outstanding packets

Indicates the number of SA GMP packets that are currently queued up per second.

Packets/sec

 

GMP packets received

Indicates the total number of SA GMP packets received per second since the SM was started.

Packets/sec

 

GMP packets transmitted

Indicates the total number of SA GMP packets transmitted per second since the SM was started.

Packets/sec

 

GMP unknown received packets

Indicates the number of unknown SA GMP packets received per second.

Packets/sec

 

GMP ignored packets

Indicates the number of SA GMP packets ignored per second.

Packets/sec

The SA GMP packets are ignored from transmission when the SM is not a master or is not yet ready to handle SA requests.

SMInfo request received

Indicates the number of SMInfo requests received per second.

Packets/sec

 

SMInfo request transmitted

Indicates the number of SMInfo requests transmitted per second.

Packets/sec

 

SMInfo response received

Indicates the number of SMInfo responses received per second.

Packets/sec

 

SMInfo response transmitted

Indicates the number of SMInfo responses transmitted per second.

Packets/sec