Default Parameters for TopApplicationTest
This test helps administrators tackle this challenge! This test automatically discovers the top-n applications/protocols in terms of the volume of traffic they generate, and reports the following:
how much data is transmitted/received by each application/protocol through every interface on the target Netflow device; how much bandwidth resources are used by each application/protocol through every interface on the target Netflow device;
This page depicts the default parameters that need to be configured for the TopApplicationTest test.
By default, for each interface that the target Netflow device supports, this test reports metrics for only the top-10 applications/protocols that handle over 3% of the total traffic on that interface. Also, by default, the test will report detailed diagnostics for only the top-5 applications/protocols that handle over 3% of the total traffic on that interface. This default setting enables network administrators to focus on the abnormal flows alone. This behavior is governed by the default setting of the FILTER BY, MINIMUM FLOW PERCENT, REPORT TOP N FLOWS, and SHOW DD FOR TOP N FLOWS parameters. By default, the FILTER BY option is set to % Traffic and the MINIMUM FLOW PERCENT is set to 3 (%). You can increase or decrease the MINIMUM FLOW PERCENT depending upon the level of traffic that you deem as abnormal. Also, by default, the REPORT TOP N FLOWS is set to 10 and SHOW DD FOR TOP N FLOWS is set to 5. You can increase or decrease the value of these two parameters depending upon the level of visibility you require.
You can also override the FILTER BY default setting and have this test report real-time metrics and detailed diagnostics for only those applications/protocols (per interface) that use over a configured percentage of bandwidth resources. For this, set FILTER BY to Bandwidth Used and configure a bandwidth usage limit (in %) against MINIMUM FLOW PERCENT. This way, administrators can focus on only those applications/protocols that generate bandwidth-intensive traffic.
Provide a comma-separated list of interfaces that you want excluded from monitoring in the EXCLUDE INTERFACES text box. For example, your specification can be, FastEtherNet0/0, FastEthernet0/1,FastEtherNet0/2. You can even provide patterns of interfaces as a comma-separated list - for instance, *ethernet*,Fast*.
This test captures statistics on traffic to/from applications, where each application is by default represented by its IP address in the eG monitoring console. Accordingly, the SHOW HOST NAMES flag is set to No by default. You can set this flag to Yes so that the names of the individual hosts are displayed in the eG monitoring console instead of their IP addresses.
By default, the IGNORE LOCAL TRAFFIC flag is set to Yes, indicating that the test will ignore the applications/protocols responsible for all the intranet traffic on the target NetFlow device. If you want the test to report metrics pertaining to the applications/protocols responsible for local traffic as well, set this flag to No.
Network latencies and processing bottlenecks can sometimes cause netflow records to be transmitted slowly to the NetFlow collector. In such a situation, you can instruct the collector to either process or ignore the delayed NetFlow records. If you want the metrics reported to pertain to current NetFlow records only, then you may choose to ignore the delayed records. In this case, set the PROCESS TAINTED PACKETS flag to No. If you want old NetFlow records to also be considered when identifying top sources and reporting their traffic statistics, then set the PROCESS TAINTED PACKETS flag to Yes. Typically, any NetFlow record that takes 10 minutes or over to reach the NetFlow collector is deemed a tainted/delayed record.
By default, NetFlow is designed to process all IP packets on an interface. This is why, the SAMPLING flag is set to No by default. In some environments however, e.g. on Internet backbones, processing all IP packets can be too costly, due to the extra processing required for each packet and large number of simultaneous flows. This is where sampling is useful. In such environments, set the SAMPLING flag to Yes.
Once this is done, then each interface will process only 1 packet out of a configured number of packets. Specify the number of packets from which this 1 packet should be picked in the SAMPLING RATE text box. For instance, to pick 1 out of 1000 packets for sampling, set the SAMPLING RATE to 1000. Where Sampling is enabled, all NetFlow metrics - particularly, metrics on traffic volume - will be adjusted based on the SAMPLING RATE you specify.
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.
The SNMP community name that the test uses to communicate with the switch. The SNMPCOMMUNITY parameter is specific to SNMP v1 and v2 only. Therefore, if the SNMPVERSION chosen is v3, then this parameter will not appear.
The USERNAME 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.
The CONTEXT 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.
The AUTHTYPE 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:
The ENCRYPTFLAG appears only when v3 is selected as the SNMPVERSION. By default, the eG agent does not encrypt SNMP requests. Accordingly, the ENCRYPTFLAG is set to No by default. To ensure that SNMP requests sent by the eG agent are encrypted, select the Yes option.
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 the DATA OVER TCP flag to Yes. By default, this flag is set to No.
The DD FREQUENCY refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD FREQUENCY.
When changing default configurations of tests, the values with “$” indicate variables that will be replaced by the eG system according to the specific server being managed - for instance, $hostName is the host/nickname of the target host, $port is the port number of the server being monitored. E.g., for a server xyz:80, $hostName will be changed automatically by the eG manager to “xyz*” and $port will be changed to “80” when configuring a test.
|