A10 Service Groups Test
In a typical client – server scenario, a client request is directed to the destination IP address specified in the header of the request. For sites with huge volumes of traffic, the destination server may be quickly overloaded, Therefore, it is imperative to create a load balancing pool which is in other words called a service group in an A10 Application Delivery Controller. A service group is a logical set of real servers, such as web servers, that you group together to receive and process traffic. Instead of sending client traffic to the destination IP address specified in the client request, the Virtual server of the A10 Application Delivery Controller sends the request to any of the servers that are members of that service group. This helps to efficiently distribute the load on your server resources. In order to efficiently distribute the load across the servers, it is essential to constantly monitor the health and request processing capability of the service groups. This is where the A10 Service Group test helps.
For each service group configured on the A10 Application Delivery Controller, this test monitors the current health and reveals the request processing ability of the service groups. Using this test, administrator can figure out the service group that is handling the maximum requests and also identify the exact cause on why a service group is slow in processing the requests.
Target of the test : An A10 Application Delivery Controller
Agent deploying the test : An external agent
Outputs of the test : One set of results for each service group on the target A10 Application Delivery Controller being monitored.
Parameter | Description |
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Test period |
How often should the test be executed |
Host |
The IP address of the A10 Application Delivery Controller 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 firewall. 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:
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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. |
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. |
EncryptType |
If the 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:
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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. |
Measurement | Description | Measurement Unit | Interpretation | ||||||||
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Health status |
Indicates the current health of this service group. |
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The values of this measure and their corresponding numeric values are listed below:
Note: By default, this measure reports one of the Measure Values listed in the table above to indicate the current health of the service group. In the graph of this measure however, the health of the service group will be represented using the numeric equivalents. |
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Data transmitted |
Indicates the rate at which data was transmitted from this service group during the last measurement period. |
MB/Sec |
Compare the values of these measures across service groups to identify the service group that is handling maximum traffic. |
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Data received |
Indicates the rate at which data was received by this service group during the last measurement period. |
MB/Sec |
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Packets transmitted |
Indicates the rate at which the packets were transmitted from this service group during the last measurement period. |
Packets/Sec |
Compare the value of these measures across the service groups to identify the service group that is experiencing the maximum traffic. |
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Packets received |
Indicates the rate at which packets were received by this service group during the last measurement period. |
Packets/Sec |
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Active connections |
Indicates the number of connections that are currently active on this service group. |
Number |
This measure is a good indicator of the load on the service group. |
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Total connections |
Indicates the total number of connections established on this service group since the start of the A10 Application Delivery Controller. |
Number |
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Connection rate |
Indicates the rate at which the connections were established on this service group during the last measurement period. |
Conns/Sec |
A sudden increase in the value of this measure indicates an increase in the load on the service group. |
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Connection usage |
Indicates the percentage of connections used by this service group. |
Percent |
A value close to 100% indicates that the service group is currently overloaded. |
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Persistent connections |
Indicates the number of connections that were persistent on this service group. |
Number |
TCP connections that are kept open after transactions complete are called persistent connections. Persistent connections stay open across transactions, until either the client or the server decides to close them. These connections when reused can significantly reduce the overload on the new connections to the service group. |
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Peak connections |
Indicates the maximum number of connections that were established on this service group since the start of the A10 Application Delivery Controller. |
Number |
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L7 requests |
Indicates the number of L7 requests currently processed by this service group. |
Number |
Both these measures serve as effective pointers to the L7 requests processing in the A10 Application Delivery Controller. Layer-7 load balancing, also known as application-level load balancing, is to parse L7 requests in application layer and distribute L7 requests to the servers based on different types of request content, so that it can provide quality of service requirements for different types of content and improve overall performance. |
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L7 request rate |
Indicates the rate at which the L7 requests were processed by this service group. |
Requests/Sec |
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Successful L7 requests |
Indicates the number of L7 requests that were processed successfully by this service group. |
Number |
Ideally the value of this measure should be high. |