Cisco Buffers Test

This test monitors the memory allocations within a Cisco router. Various forms of buffer memory allocation failures are tracked and reported. This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick the Cisco Router as the desired Component type, set Performance as the Test type, choose the test from the disabled tests list, and click on the < button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A Cisco router

Agent deploying the test : An external agent

Outputs of the test : One set of results for every router being monitored.

Configurable parameters for the test
Parameters	Description
Test period	How often should the test be executed
Host	The IP address of the Cisco Router.
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 SHA224 - Secure Hash Algorithm 224 bit SHA256 - Secure Hash Algorithm 256 bit SHA384 - Secure Hash Algorithm 384 bit SHA512 - Secure Hash Algorithm 512 bit
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: DES - Data Encryption Standard 3DES - Triple Data Encryption Standard AES - Advanced Encryption Standard AES128 - Advanced Encryption Standard 128 bit AES192 - Advanced Encryption Standard 192 bit AES256 - Advanced Encryption Standard 256 bit
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
No memory errors	Counts the number of buffer creation failures due to lack of free memory in the router	Number	Lack of free memory can result in poor performance by a router - packet drops, packet processing slowdown, etc. can happen. By monitoring when memory errors happen, an administrator can proactively detect performance bottlenecks caused by a router. If memory errors occur often, consider upgrading the memory on the router.
Small buffer misses	Counts the number of allocations that failed because there were no small buffers available	Number	Ideally, the small buffer miss count should be 0. Repeated buffer misses indicates a memory bottleneck in the router. Alternatively, the maximum number of small buffers set when configuring the router may be too low for the traffic being handled.
Medium buffer misses	Counts the number of allocations that failed because there were no medium buffers available	Number	Ideally, the medium buffer miss count should be 0. Repeated buffer misses indicates a memory bottleneck in the router. Alternatively, the maximum number of medium buffers set when configuring the router may be too low for the traffic being handled.
Large buffer misses	Counts the number of allocations that failed because there were no large buffers available	Number	Ideally, the large buffer miss count should be 0. Repeated buffer misses indicates a memory bottleneck in the router. Alternatively, the maximum number of large buffers set when configuring the router may be too low for the traffic being handled.
Huge buffer misses	Counts the number of allocations that failed because there were no huge buffers available	Number	Ideally, the large buffer miss count should be 0. Repeated buffer misses indicates a memory bottleneck in the router. Alternatively, the maximum number of huge buffers set when configuring the router may be too low for the traffic being handled.
Big buffer misses	Counts the number of allocations that failed because there were no big buffers available.	Number	Ideally, the big buffer miss count should be 0. Repeated buffer misses indicates a memory bottleneck in the router. Alternatively, the maximum number of big buffers set when configuring the router may be too low for the traffic being handled.
Buffer hits	Indicates the total number of buffer hits.	Number	Ideally, the value of this measure should be high. A very low value could indicate that many allocations have failed owing to the lack of adequate buffers. If the measure repeatedly reports low values, it could be indicative of a memory bottleneck on the router.