High Availability Status Test

Radware's new High Availability module supports two redundancy modes:

  • Switch mode
  • Service mode

The Service mode is a redundancy scenario involving 2 devices where each device is both the Active device for some VIPs (i.e., virtual servers) and the Backup device for other VIPs. In the event of a failure of one device, the other device temporarily assumes ownership of all VIPs. To support the Service mode, virtual servers need to be grouped into high availability service groups. In the Service mode, each load-balancing device will be configured as an active or backup device for every service group. This way, when a device fails, the service group for which the failed device is configured as the active device will automatically switch to the device that has been configured as its backup device. Once the active device comes back up, the service group will switch back to it.

At any give point in time, an administrator should know which service groups are enabled for HA, and whether a load balancer is the Active or the Backup device for a service group. This can be determined using the High Availability Status test.

This test auto-discovers service groups, and for each service group, reports whether that service group is enabled for HA or not. Additionally, the test also reveals the HA status of the monitored load balancer for that service group.

Target of the test : A Radware Alteon Load Balancer

Agent deploying the test : An external agent

Outputs of the test : One set of results for each service group

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The IP address of the Radware Alteon load balancer 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:

  • 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

Is service group enabled?

Indicates whether or not this service group is enabled.

 

The values that this measure can report and their corresponding numeric values are as follows:

Measure Value

Numeric Value

Yes

1

No

0

Note:

By default, this test reports one of the Measure Values listed in the table above to indicate the status of the service group. In the graph of the measure however, the same is indicated using the corresponding numeric equivalents only.

Service group status

Indicates the current HA status of the target load balancer for this service group.

 

This measure can report one of the following values:

  • Init: HA is ON but cannot start
  • Backup: HA is ON and the device is in Backup/standby state
  • Master: HA is ON and the device is in Master state
  • Holdoff: HA is ON and currently in holdoff period

The numeric values that correspond to the measure values described above are as follows:

Measure Value

Description

Init

0

Backup

1

Master

2

Holdoff

3

Note:

By default, this test reports one of the Measure Values listed in the table above to indicate the status of the service group. In the graph of the measure however, the same is indicated using the corresponding numeric equivalents only.