Memory Statistics Test
This test monitors the available and used memory of a BIG-IP load balancer. The Net-SNMP MIB is polled by this test to extract the metrics below:
Target of the test : A BIG-IP Load Balancer
Agent deploying the test : An external agent
Outputs of the test : One set of results for the BIG-IP load balancer being monitored
Parameters | Description |
---|---|
Test Period |
How often should the test be executed. |
Host |
The IP address of the host for which this test is to be configured. |
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:
|
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 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:
|
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. |
Measurement | Description | Measurement Unit | Interpretation |
---|---|---|---|
Total real memory |
Indicates the total real memory space on the host. |
MB |
|
Available memory |
Indicates the available real/physical memory space on the host. |
MB |
Ideally, this value should be high. |
Free virtual memory |
Indicates available virtual memory on the host. |
MB |
|
Total swap memory |
Indicates the total swap size configured for the host. |
MB |
|
Available swap |
Indicates the available swap space on the host. |
MB |
An unusually low value for the available swap space can indicate a memory bottleneck. Check the memory utilization of individual processes to figure out the process (es) that has (have) maximum memory consumption and look to tune their memory usages and allocations accordingly. |
Swap memory errors |
Indicates whether adequate swap space is available or not. |
Boolean |
A value of 1 indicates that there is very little swap space left. A value of 0 indicates normalcy with respect to available swap space. |
Shared memory usage |
Indicates the total shared memory on the host. |
MB |
|
Buffered memory |
Indicates the total buffered memory on the host. |
MB |
|
Cached memory |
Indicates the total cached memory on the host. |
MB |
|
Memory swap ins |
Indicates the amount of memory swapped in from disk per second. |
KB/Sec |
|
Memory swap outs |
Indicates the amount of memory swapped out to disk per second. |
KB/Sec |
|