Table Of Contents
Configuring NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
Prerequisites for Configuring NetFlow Top Talkers
Restrictions for Configuring NetFlow Top Talkers
Information About Configuring NetFlow Top Talkers
Overview of the NetFlow MIB and Top Talkers Feature
Benefits of the NetFlow MIB and Top Talkers Feature
Cisco IOS Release 12.2(33)SXH on Cisco 6500 Series Switches
How to Configure NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
Configuring SNMP Support on the Networking Device
Configuring Parameters for the NetFlow Main Cache
Identifying the Interface Number to Use for Enabling NetFlow with SNMP
Configuring NetFlow on a Cisco 6500 Series Switch
Configuring NetFlow on Cisco Routers
Configuring NetFlow Top Talkers
Configuring NetFlow Top Talkers Match Criteria
NetFlow Top Talkers Match Criteria Specified by CLI Commands
Configuring Source IP Address Top Talkers Match Criteria
Verifying the NetFlow Top Talkers Configuration
Configuration Examples for NetFlow Top Talkers
Configuring NetFlow Top Talkers Using SNMP Commands: Example
Configuring NetFlow Top Talkers Match Criteria Using SNMP Commands: Example
Feature Information for Configuring NetFlow Top Talkers using the Cisco IOS CLI or SNMP Commands
Configuring NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
First Published: May 02, 2005Last Updated: October 02, 2009This module contains information about and instructions for configuring NetFlow Top Talkers feature. The NetFlow Top Talkers feature can be configured using the Cisco IOS command-line interface (CLI) or with SNMP commands using the NetFlow MIB. The NetFlow Top Talkers feature uses NetFlow functionality to obtain information regarding heaviest traffic patterns and most-used applications in the network. The NetFlow MIB allows you to configure NetFlow and the NetFlow Top Talkers feature using SNMP commands from a network management workstation.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for Configuring NetFlow Top Talkers using the Cisco IOS CLI or SNMP Commands" section.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note
If you are searching in Feature Navigator, the feature documented in this module is named NetFlow MIB and Top Talkers.
Contents
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Prerequisites for Configuring NetFlow Top Talkers
•
Restrictions for Configuring NetFlow Top Talkers
•
Information About Configuring NetFlow Top Talkers
•
How to Configure NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
•
Configuration Examples for NetFlow Top Talkers
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Feature Information for Configuring NetFlow Top Talkers using the Cisco IOS CLI or SNMP Commands
Prerequisites for Configuring NetFlow Top Talkers
Before you enable NetFlow and NetFlow Top Talkers, you must:
•
Configure the router for IP routing
•
Ensure that one of the following is enabled on your router, and on the interfaces that you want to configure NetFlow on: Cisco Express Forwarding (CEF), distributed CEF, or fast switching
•
Understand the resources required on your router because NetFlow consumes additional memory and CPU resources.
Restrictions for Configuring NetFlow Top Talkers
Cisco IOS Releases 12.2(14)S, 12.0(22)S, or 12.2(15)T
If your router is running a version of Cisco IOS prior to releases 12.2(14)S, 12.0(22)S, or 12.2(15)T the ip route-cache flow command is used to enable NetFlow on an interface.
If your router is running Cisco IOS release 12.2(14)S, 12.0(22)S, 12.2(15)T, or later the ip flow ingress command is used to enable NetFlow on an interface.
Cisco IOS Release 12.2(33)SXH
Some of the keywords and arguments for the commands used to configure the NetFlow MIB and Top Talkers feature are not supported in 12.2(33)SXH. See the syntax descriptions for the commands in the command reference (URL for the 12.2SX NF CR to be added later) for details.
Information About Configuring NetFlow Top Talkers
•
Overview of the NetFlow MIB and Top Talkers Feature
•
Benefits of the NetFlow MIB and Top Talkers Feature
•
Cisco IOS Release 12.2(33)SXH on Cisco 6500 Series Switches
Overview of the NetFlow MIB and Top Talkers Feature
NetFlow collects traffic flow statistics on routing devices. NetFlow has been used for a variety of applications, including traffic engineering, usage-based billing, and monitoring for denial-of-service (DoS) attacks.
The flows that are generating the heaviest system traffic are known as the "top talkers."
The NetFlow Top Talkers feature allows flows to be sorted so that they can be viewed. The top talkers can be sorted by either of the following criteria:
•
By the total number of packets in each top talker
•
By the total number of bytes in each top talker
The usual implementation of NetFlow exports NetFlow data to a collector. The NetFlow MIB and Top Talkers feature performs security monitoring and accounting for top talkers and matches and identifies key users of the network. This feature is also useful for a network location where a traditional NetFlow export operation is not possible. The NetFlow MIB and Top Talkers feature does not require a collector to obtain information regarding flows. Instead, these flows are placed in a special cache where they can be viewed. The NetFlow MIB part of the NetFlow MIB and Top Talkers feature allows you to configure the NetFlow Top Talkers feature using SNMP.
In addition to sorting top talkers, you can further organize your output by specifying criteria that the top talkers must match, such as source or destination IP address or port. The match command is used to specify this criterion. For a full list of the matching criteria that you can select, refer to the match command in the Cisco IOS command reference documentation.
Benefits of the NetFlow MIB and Top Talkers Feature
Top talkers can be useful for analyzing network traffic in any of the following ways:
•
Security—You can view the list of top talkers to see if traffic patterns consistent with DoS attack are present in your network.
•
Load balancing—You can identify the most heavily used parts of the system and move network traffic over to less-used parts of the system.
•
Traffic analysis—Consulting the data retrieved from the NetFlow MIB and Top Talkers feature can assist you in general traffic study and planning for your network.
An additional benefit of the NetFlow MIB and Top Talkers feature is that it can be configured for a router either by entering CLI commands or by entering SNMP commands on a network management system (NMS) workstation. The SNMP commands are sent to the router and processed by a MIB. You do not have to be connected to the router console to extract the list of top talkers information if an NMS workstation is configured to communicate using SNMP to your network device. For more information on configuring your network device to use MIB functionality for the NetFlow MIB and Top Talkers feature, see Configuring SNMP Support on the Networking Device.
Cisco IOS Release 12.2(33)SXH on Cisco 6500 Series Switches
The show ip flow top-talkers command was modified in Cisco IOS Release 12.2(33)SXH for the Cisco 6500 Series switches to support displaying the top talkers for a specific module. The show ip flow top-talkers module number command displays the top talkers for that module. The show ip flow top-talkers command without the module keyword shows the top talkers in the hardware switched path (a merged list of top lists from all modules) and then software switched top talkers. The NetFlow MIB can be used to request the top talker list and to set and/or get the configuration parameters for the NetFlow MIB Top Talkers feature.
How to Configure NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
Note
Some of the tasks in this section include examples of the SNMP CLI syntax used to set configuration parameters on the router and to read values from MIB objects on the router. These SNMP CLI syntax examples are taken from a Linux workstation using public-domain SNMP tools. The SNMP CLI syntax for your workstation might be different. Refer to the documentation that was provided with your SNMP tools for the correct syntax for your network management workstation.
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Configuring SNMP Support on the Networking Device
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Configuring Parameters for the NetFlow Main Cache
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Identifying the Interface Number to Use for Enabling NetFlow with SNMP
•
Configuring NetFlow on a Cisco 6500 Series Switch
•
Configuring NetFlow on Cisco Routers
•
Configuring NetFlow Top Talkers
•
Configuring NetFlow Top Talkers Match Criteria
•
Verifying the NetFlow Top Talkers Configuration
Configuring SNMP Support on the Networking Device
If you want to configure the NetFlow Top Talkers feature using the Cisco IOS CLI, you do not have to perform this task.
If you want to configure the NetFlow Top Talkers feature using the NetFlow MIB and SNMP, you must perform this task.
Before you can use SNMP commands to configure the Top Talkers feature you must configure SNMP support on your networking device. To enable SNMP support on the networking device perform the steps in this task.
Note
The SNMP community read-only (RO) string for the examples is public. The SNMP community read-write (RW) string for the examples is private. You should use more complex strings for these values in your configurations.
Note
For more information on configuring SNMP support on your networking device, refer to the "Configuring SNMP Support" chapter of the Cisco IOS Configuration Fundamentals and Network Management Configuration Guide.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
snmp-server community string ro
4.
snmp-server community string rw
5.
end
DETAILED STEPS: Router CLI Commands
Configuring Parameters for the NetFlow Main Cache
This optional task describes the procedure for modifying the parameters for the NetFlow main cache. Perform the steps in this optional task using either the router CLI commands or the SNMP commands to modify the parameters for the NetFlow main cache.
SUMMARY STEPS
Router CLI Commands
1.
enable
2.
configure terminal
3.
ip flow-cache entries number
4.
ip flow-cache timeout active minutes
5.
ip flow-cache timeout inactive seconds
6.
end
SNMP Commands
1.
snmpset -c private -m all -v2c [ip-address | hostname] cnfCICacheEntries.type unsigned number
2.
snmpset -c private -m all -v2c [ip-address | hostname] cnfCIActiveTimeOut.type unsigned number
3.
snmpset -c private -m all -v2c [ip-address | hostname] ccnfCIInactiveTimeOut.type unsigned number
DETAILED STEPS: Router CLI Commands
DETAILED STEPS: SNMP Commands
Identifying the Interface Number to Use for Enabling NetFlow with SNMP
If you want to configure the NetFlow Top Talkers feature using the Cisco IOS CLI, you do not have to perform this task.
If you want to configure the NetFlow Top Talkers feature using the NetFlow MIB and SNMP, you must perform this task.
Before you can use SNMP to enable NetFlow on an interface, you must identify the SNMP interface number on the router. To identify the interface number for the interface on which you want to enable NetFlow, perform the steps in this required task.
SUMMARY STEPS
1.
enable
2.
show snmp mib ifmib ifindex type number
3.
Repeat Step 2 to identify the SNMP interface number for any other interfaces on which you plan to enable NetFlow.
DETAILED STEPS
Step 1
enable
Enters privileged EXEC mode. Enter the password if prompted.
Router> enableStep 2
show snmp mib ifmib ifindex type number
Displays the SNMP interface number for the interface specified.
Router# show snmp mib ifmib ifindex GigabitEthernet6/2Ethernet0/0: Ifindex = 60Step 3
Repeat Step 2 to identify the SNMP interface number for any other interfaces on which you plan to enable NetFlow.
Configuring NetFlow on a Cisco 6500 Series Switch
To enable NetFlow on the switch, perform the steps in this required task using either the CLI commands or the SNMP commands.
Note
This task provides the minimum information required to configure NetFlow on your Cisco 6500 series switch. See the Catalyst 6500 Series Cisco IOS Software Configuration Guide, for more information of configuring NetFlow on your switch.
SUMMARY STEPS
Router CLI Commands
1.
enable
2.
configure terminal
3.
mls flow {ip | ipv6} {destination | destination-source | full | interface-destination-source | interface-full | source}
4.
interface type number
5.
ip flow {ingress | egress}
6.
exit
7.
Repeat Steps 4 through 6 to enable NetFlow on other interfaces.
8.
end
SNMP Commands
1.
snmpset -c private -m all -v2c [ip-address | hostname] cseFlowIPFlowMask integer [1 | 2 | 3 | 4 | 5 | 6]
2.
snmpset -c private -m all -v2c [ip-address | hostname] cnfCINetflowEnable.interface-number integer [0 | 1 | 2 | 3]
3.
Repeat Step 2 to enable NetFlow on other interfaces.
DETAILED STEPS: Router CLI Commands
DETAILED STEPS: SNMP Commands
Configuring NetFlow on Cisco Routers
To enable NetFlow on the router, perform the steps in this required task using either the CLI commands or the SNMP commands .
SUMMARY STEPS
Router CLI Commands
1.
enable
2.
configure terminal
3.
interface type number
4.
ip flow {ingress | egress}
5.
exit
6.
Repeat Steps 3 through 5 to enable NetFlow on other interfaces.
7.
end
SNMP Commands
1.
snmpset -c private -m all -v2c [ip-address | hostname] cnfCINetflowEnable.interface-number integer [0 | 1 | 2 | 3]
2.
Repeat Step 1 to enable NetFlow on other interfaces.
DETAILED STEPS: Router CLI Commands
DETAILED STEPS: SNMP Commands
Configuring NetFlow Top Talkers
This task describes the procedure for configuring the NetFlow Top Talkers feature. Perform the steps in this required task using either the router CLI commands or the SNMP commands to configure the NetFlow Top Talkers feature on the router.
SUMMARY STEPS
Router CLI Commands
1.
enable
2.
configure terminal
3.
ip flow-top-talkers
4.
top number
5.
sort by [bytes | packets]
6.
cache-timeout milliseconds
7.
end
SNMP Commands
1.
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsTopN.0 unsigned number
2.
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsSortBy.0 integer [1 | 2 | 3]
3.
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsCacheTimeout.0 unsigned milliseconds
DETAILED STEPS: Router CLI Commands
DETAILED STEPS: SNMP Commands
Configuring NetFlow Top Talkers Match Criteria
You can limit the traffic that is displayed by the NetFlow Top Talkers feature by configuring match criteria. The match criteria are applied to data in the main cache. The data in the main cache that meets the match criteria is displayed when you enter the show ip flow top-talkers command. To limit the traffic that is displayed by the NetFlow MIB and Top Talkers feature, perform the steps in this optional task.
Before configuring NetFlow MIB and Top Talkers match criteria, you should understand the following:
•
NetFlow Top Talkers Match Criteria Specified by CLI Commands
•
NetFlow Top Talkers Match Criteria Specified by SNMP Commands
NetFlow Top Talkers Match Criteria Specified by CLI Commands
You can use the match CLI command to specify match criteria to restrict the display of top talkers for the NetFlow MIB and Top Talkers feature. If you do not provide matching criteria, all top talkers are displayed.
Note
When configuring a matching source, destination or nexthop address, both the address and a mask must be configured. The configuration will remain unchanged until both have been specified.
Note
cnfTopFlowsMatchSampler matches flows from a named flow sampler. cnfTopFlowsMatchClass matches flows from a named class map.
Note
When you are configuring the Top Talkers feature to match bytes and packets, the values that are matched are the total number of bytes and packets in the flow so far. For example, it is possible to match flows containing a specific number of packets, or flows with more or less than a set number of bytes.
For more information on using the match command, see the Cisco IOS NetFlow Command Reference.
NetFlow Top Talkers Match Criteria Specified by SNMP Commands
If you are using SNMP commands to configure NetFlow Top Talkers, see Table 1 for router CLI commands and equivalent SNMP commands.
Note
Some of the SNMP match criteria options, such as the cnfTopFlowsMatchSrcAddress option, require that you enter more than one SNMP commands on the same line. For example, snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsMatchSrcAddressType.0 integer 1 cnfTopFlowsMatchSrcAddress.0 decimal 172.16.10.0 cnfTopFlowsMatchSrcAddressMask.0 unsigned 24.
Table 1 Router CLI Commands and Equivalent SNMP Commands
Router CLI Command SNMP Commandmatch source address [ip-address] [mask | /nn]
cnfTopFlowsMatchSrcAddress decimal ip-address
cnfTopFlowsMatchSrcAddressType integer type1
cnfTopFlowsMatchSrcAddressMask unsigned mask
match destination address [ip-address] [mask | /nn]
cnfTopFlowsMatchDstAddress decimal ip-address
cnfTopFlowsMatchDstAddressType integer type1
cnfTopFlowsMatchDstAddressMask unsigned mask
match nexthop address [ip-address] [mask | /nn]
cnfTopFlowsMatchNhAddress decimal ip-address
cnfTopFlowsMatchNhAddressType integer type1
cnfTopFlowsMatchNhAddressMask unsigned mask
match source port min port
cnfTopFlowsMatchSrcPortLo integer port
match source port max port
cnfTopFlowsMatchSrcPortHi integer port
match destination port min port
cnfTopFlowsMatchDstPortLo integer port
match destination port max port
cnfTopFlowsMatchDstPortHi integer port
match source as as-number
cnfTopFlowsMatchSrcAS integer as-number
match destination as as-number
cnfTopFlowsMatchDstAS integer as-number
match input-interface interface
cnfTopFlowsMatchInputIf integer interface
match output-interface interface
cnfTopFlowsMatchOutputIf integer interface
match tos [tos-value | dscp dscp-value | precedence precedence-value]
cnfTopFlowsMatchTOSByte integer tos-value2
match protocol [protocol-number | tcp | udp]
cnfTopFlowsMatchProtocol integer protocol-number
match flow-sampler flow-sampler-name
cnfTopFlowsMatchSampler string flow-sampler-name
match class-map class
cnfTopFlowsMatchClass string class
match packet-range min minimum-range
cnfTopFlowsMatchMinPackets unsigned minimum-range
match packet-range max maximum-range
cnfTopFlowsMatchMaxPackets unsigned maximum-range
match byte-range min minimum-range
cnfTopFlowsMatchMinBytes unsigned minimum-range
match byte-range max maximum-range
cnfTopFlowsMatchMaxPackets unsigned maximum-range
1 The only IP version type that is currently supported is IPv4 (type 1).
2 tos-value is 6 bits for DSCP, 3 bits for precedence, and 8 bits (one byte) for ToS.
Configuring Source IP Address Top Talkers Match Criteria
Perform the steps in this optional task using either the router CLI commands or the SNMP commands to add source IP address match criteria to the Top Talkers configuration.
For information on configuring other Top Talkers match criteria see the following resources:
•
Cisco IOS NetFlow Command Reference.
•
CISCO-NETFLOW-MIB at the following URL: http://www.cisco.com/go/mibs/. Select SNMP Object Locator. Then select View & Download MIBs.
Prerequisites
You must configure NetFlow Top Talkers before you perform this task.
SUMMARY STEPS
Router CLI Commands
1.
enable
2.
configure terminal
3.
ip flow-top-talkers
4.
match source address {ip-address/nn | ip-address mask}
5.
end
SNMP Commands
1.
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsMatchSrcAddressType.0 integer 1 cnfTopFlowsMatchSrcAddress.0 decimal ip-address cnfTopFlowsMatchSrcAddressMask.0 unsigned mask
DETAILED STEPS: Router CLI Commands
Command or Action PurposeStep 1
enable
Example:Router> enable
(Required) Enables privileged EXEC mode.
•
Enter your password if prompted.
Step 2
configure terminal
Example:Router# configure terminal
(Required) Enters global configuration mode.
Step 3
ip flow-top-talkers
Example:Router(config)# ip flow-top-talkers
(Required) Enters NetFlow Top Talkers configuration mode.
Step 4
match source address {ip-address/nn | ip-address mask}
Example:Router(config-flow-top-talkers)# match source address 172.16.10.0/24
(Required) Specifies a match criterion.
•
The source address keyword specifies that the match criterion is based on the source IP address.
•
The ip-address argument is the IP address of the source, destination, or next-hop address to be matched.
•
The mask argument is the address mask, in dotted decimal format.
•
The /nn argument is the address mask as entered in CIDR format. The match source address 172.16.10.0/24 is equivalent to the match source address 172.16.10.0 255.255.255.0 command.
Note
You must configure at least one of the possible match criteria before matching can be used to limit the traffic that is displayed by the NetFlow Top Talkers feature. Additional match criteria are optional.
Note
For a full list of the matching criteria that you can select, refer to NetFlow Top Talkers Match Criteria Specified by CLI Commands.
Step 5
end
Example:Router(config-flow-top-talkers)# end
(Required) Exits the current configuration mode and returns to privileged EXEC mode.
DETAILED STEPS: SNMP Commands
Command or Action PurposeStep 1
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsMatchSrcAddressType.0 integer 1 cnfTopFlowsMatchSrcAddress.0 decimal ip-address cnfTopFlowsMatchSrcAddressMask.0 unsigned mask
Example:workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsMatchSrcAddressType.0 integer 1 cnfTopFlowsMatchSrcAddress.0 decimal 172.16.10.0 cnfTopFlowsMatchSrcAddressMask.0 unsigned 24
(Required) Specifies a match criterion.
•
The IP address type of 1 in the cnfTopFlowsMatchSrcAddressType.0 integer 1 command specifies an IP version 4 (IPv4) address for the IP address type. IPv4 is currently the only IP version that is supported.
•
The ip-address argument in cnfTopFlowsMatchSrcAddress.0 decimal ip-address is the IPv4 source IP address to match in the traffic that is being analyzed.
•
The mask argument in cnfTopFlowsMatchSrcAddressMask.0 unsigned mask is the number of bits in the mask for the IPv4 source IP address to match in the traffic that is being analyzed.
Note
You must configure at least one of the possible match criteria before matching can be used to limit the traffic that is displayed by the Top talkers feature. Additional match criteria are optional.
Note
To remove the cnfTopFlowsMatchSrcAddress match criterion from the configuration, specify an IP address type of 0 (unknown) with the cnfTopFlowsMatchSrcAddressType.0 integer 0 command.
Note
For a list of router CLI commands and their corresponding SNMP commands, see Table 1.
Verifying the NetFlow Top Talkers Configuration
To verify the NetFlow Top Talkers configuration, perform the steps in this optional task using either the router CLI command or the SNMP commands.
SUMMARY STEPS
Router CLI Commands
1.
show ip flow top-talkers
SNMP Command
1.
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsGenerate.0 integer 1
2.
snmpwalk -c public -m all -v2c [ip-address | hostname] cnfTopFlowsReportAvailable
3.
snmpwalk -c public -m all -v2c [ip-address | hostname] cnfTopFlowsTable
DETAILED STEPS: Router CLI Commands
Step 1
show ip flow top-talkers
Use this command to verify that the NetFlow MIB and Top Talkers feature is operational. For example:
Router# show ip flow top-talkersSrcIf SrcIPaddress DstIf DstIPaddress Pr SrcP DstP BytesEt3/0 10.1.1.3 Local 10.1.1.2 01 0000 0000 4800Et3/0 10.1.1.4 Local 10.1.1.2 01 0000 0000 4800Et3/0 10.1.1.5 Local 10.1.1.2 01 0000 0000 8003 of 10 top talkers shown. 3 flows processed.In this example, even though a maximum of ten top talkers is configured by the top command, only three top talkers were transmitting data in the network. Therefore, three top talkers are shown, and the "3 flows processed" message is displayed in the output. If you expect more top talkers to be displayed than are being shown, this condition may possibly be the result of matching criteria, specified by the match command, that are overly restrictive.
DETAILED STEPS: SNMP Commands
Step 1
snmpset -c private -m all -v2c [ip-address | hostname] cnfTopFlowsGenerate.0 integer 1
Use this command to initiate a generation of the top talkers statistics:
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsGenerate.0 integer 1CISCO-NETFLOW-MIB::cnfTopFlowsGenerate.0 = INTEGER: true(1)Step 2
snmpget -c public -m all -v2c [ip-address | hostname] cnfTopFlowsReportAvailable
Use this command to verify that the top talkers statistics are available:
workstation% snmpwalk -c public -m all -v2c 10.4.9.62 cnfTopFlowsReportAvailableCISCO-NETFLOW-MIB::cnfTopFlowsReportAvailable.0 = INTEGER: true(1)Step 3
snmpwalk -c public -m all -v2c [ip-address | hostname] cnfTopFlowsTable
Use this command to display the NetFlow top talkers:
workstation% snmpwalk -c public -m all -v2c 10.4.9.62 cnfTopFlowsTableCISCO-NETFLOW-MIB::cnfTopFlowsSrcAddressType.1 = INTEGER: ipv4(1)CISCO-NETFLOW-MIB::cnfTopFlowsSrcAddress.1 = Hex-STRING: 0A 04 09 08CISCO-NETFLOW-MIB::cnfTopFlowsSrcAddressMask.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsDstAddressType.1 = INTEGER: ipv4(1)CISCO-NETFLOW-MIB::cnfTopFlowsDstAddress.1 = Hex-STRING: 0A 04 09 A7CISCO-NETFLOW-MIB::cnfTopFlowsDstAddressMask.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsNhAddressType.1 = INTEGER: ipv4(1)CISCO-NETFLOW-MIB::cnfTopFlowsNhAddress.1 = Hex-STRING: 00 00 00 00CISCO-NETFLOW-MIB::cnfTopFlowsSrcPort.1 = Gauge32: 32773CISCO-NETFLOW-MIB::cnfTopFlowsDstPort.1 = Gauge32: 161CISCO-NETFLOW-MIB::cnfTopFlowsSrcAS.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsDstAS.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsInputIfIndex.1 = INTEGER: 1CISCO-NETFLOW-MIB::cnfTopFlowsOutputIfIndex.1 = INTEGER: 0CISCO-NETFLOW-MIB::cnfTopFlowsFirstSwitched.1 = Timeticks: (12073160) 1 day, 9:32:11.60CISCO-NETFLOW-MIB::cnfTopFlowsLastSwitched.1 = Timeticks: (12073160) 1 day, 9:32:11.60CISCO-NETFLOW-MIB::cnfTopFlowsTOS.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsProtocol.1 = Gauge32: 17CISCO-NETFLOW-MIB::cnfTopFlowsTCPFlags.1 = Gauge32: 16CISCO-NETFLOW-MIB::cnfTopFlowsSamplerID.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsClassID.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsFlags.1 = Gauge32: 0CISCO-NETFLOW-MIB::cnfTopFlowsBytes.1 = Gauge32: 75CISCO-NETFLOW-MIB::cnfTopFlowsPackets.1 = Gauge32: 1
Tip
You must convert the source and destination IP addresses from hexadecimal to dotted decimal format used in the display output before you can correlate them to source and destination hosts on your network. For example, in the display output above: 0A 04 09 02 = 10.4.9.2 and 0A 04 09 AF = 10.4.9.175.
Configuration Examples for NetFlow Top Talkers
•
Configuring NetFlow Top Talkers Using SNMP Commands: Example
•
Configuring NetFlow Top Talkers Match Criteria Using SNMP Commands: Example
Configuring NetFlow Top Talkers Using SNMP Commands: Example
The following output from the network management workstation shows the command and the response for enabling NetFlow on interface GigabitEthernet6/2 (ifindex number 60):
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfCINetflowEnable.60 integer 1CISCO-NETFLOW-MIB::cnfCINetflowEnable.60 = INTEGER: interfaceDirIngress(1)The following output from the network management workstation shows the command and the response for specifying 5 as the maximum number of top talkers that will be retrieved by a NetFlow top talkers query:
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsTopN.0 unsigned 5CISCO-NETFLOW-MIB::cnfTopFlowsTopN.0 = Gauge32: 5The following output from the network management workstation shows the command and the response for specifying the sort criteria for the top talkers:
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsSortBy.0 integer 2CISCO-NETFLOW-MIB::cnfTopFlowsSortBy.0 = INTEGER: byPackets(2)The following output from the network management workstation shows the command and the response for specifying the amount of time that the list of top talkers is retained:
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsCacheTimeout.0 unsigned 2000CISCO-NETFLOW-MIB::cnfTopFlowsCacheTimeout.0 = Gauge32: 2000 millisecondsConfiguring NetFlow Top Talkers Match Criteria Using SNMP Commands: Example
The following output from the network management workstation shows the snmpset command and the response for specifying the following NetFlow Top Talkers match criteria:
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Source IP address-172.16.23.0
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Source IP address mask-255.255.255.0 (/24)
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IP address type-IPv4
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsMatchSrcAddress.0 decimal 172.16.23.0 cnfTopFlowsMatchSrcAddressMask.0 unsigned 24 cnfTopFlowsMatchSrcAddressType.0 integer 1CISCO-NETFLOW-MIB::cnfTopFlowsMatchSrcAddress.0 = Hex-STRING: AC 10 17 00CISCO-NETFLOW-MIB::cnfTopFlowsMatchSrcAddressMask.0 = Gauge32: 24CISCO-NETFLOW-MIB::cnfTopFlowsMatchSrcAddressType.0 = INTEGER: ipv4(1)The following output from the network management workstation shows the snmpset command and the response for specifying the class-map my-class-map as aNetFlow Top Talkers match criterion:
workstation% snmpset -c private -m all -v2c 10.4.9.62 cnfTopFlowsMatchClass.0 s my-class-mapCISCO-NETFLOW-MIB::cnfTopFlowsMatchClass.0 = STRING: my-class-map.Additional References
Related Documents
Related Topic Document TitleOverview of Cisco IOS NetFlow
List of the features documented in the Book Title configuration guide
The minimum information about and tasks required for configuring NetFlow and NetFlow Data Export
Getting Started with Configuring NetFlow and NetFlow Data Export
Tasks for configuring NetFlow to capture and export network traffic data
Tasks for configuring Configuring MPLS Aware NetFlow
Tasks for configuring MPLS egress NetFlow accounting
Tasks for configuring NetFlow input filters
Using NetFlow Filtering or Sampling to Select the Network Traffic to Track
Tasks for configuring Random Sampled NetFlow
Using NetFlow Filtering or Sampling to Select the Network Traffic to Track
Tasks for configuring NetFlow aggregation caches
Tasks for configuring NetFlow BGP next hop support
Configuring NetFlow BGP Next Hop Support for Accounting and Analysis
Tasks for configuring NetFlow multicast support
Tasks for detecting and analyzing network threats with NetFlow
Tasks for configuring NetFlow Reliable Export With SCTP
Tasks for configuring NetFlow Layer 2 and Security Monitoring Exports
Tasks for configuring the SNMP NetFlow MIB
Configuring SNMP and using the NetFlow MIB to Monitor NetFlow Data
Information for installing, starting, and configuring the CNS NetFlow Collection Engine
Standards
Standards TitleNo new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
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MIBs
RFCs
RFCs TitleNo new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.
—
Technical Assistance
Feature Information for Configuring NetFlow Top Talkers using the Cisco IOS CLI or SNMP Commands
Table 2 lists the features in this module and provides links to specific configuration information. Only features that were introduced or modified in Cisco IOS Release 12.2(1) or 12.0(3)S or a later release appear in the table.
Not all commands may be available in your Cisco IOS software release. For details on when support for a specific command was introduced, see the command reference documentation.
For information on a feature in this technology that is not documented here, see the "Cisco IOS NetFlow Features Roadmap" module.
Cisco IOS software images are specific to a Cisco IOS software release, a feature set, and a platform. Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.
Note
Table 2 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.
Table 2 Feature Information for Configuring NetFlow Top Talkers using the Cisco IOS CLI or SNMP Commands
Feature Name Releases Feature Configuration InformationNetFlow MIB
12.3(7)T, 12.2(25)S
12.2(27)SBCThe NetFlow MIB feature provides MIB objects to allow users to monitor NetFlow cache information, the current NetFlow configuration, and statistics.
The following command was introduced by this feature: ip flow-cache timeout.
NetFlow MIB and Top Talkers
12.3(11)T,
12.2(25)S
12.2(27)SBC
12.2(33)SXHThe NetFlow MIB feature that was originally released in Cisco IOS Release12.3(7)T was modified in Cisco IOS Release 12.3(11)T to support the new NetFlow Top Talkers feature. The modifications to the NetFlow MIB and the new Top Talkers feature were released under the feature name NetFlow MIB and Top Talkers.
The NetFlow MIB and Top Talkers feature uses NetFlow functionality to obtain information regarding heaviest traffic patterns and most-used applications (top talkers) in the network. The NetFlow MIB component of the NetFlow MIB and Top Talkers feature enables you to configure top talkers and view the top talker statistics using SNMP.
The following sections provide information about this feature:
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Information About Configuring NetFlow Top Talkers
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How to Configure NetFlow Top Talkers using Cisco IOS CLI Commands or SNMP Commands
The following commands were introduced by this feature: cache-timeout, ip flow-top-talkers, match, show ip flow top-talkers, sort-by, and top.
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Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
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