Chapter 11 SNMP and Port Data Capture This module discusses the Simple Network Management Protocol (SNMP) and the BANDIT device s Port Data Capture feature, and how they can be used to augment or enhance system management in Encore Networks BANDIT products. See the following sections: Section 11.1, Simple Network Management Protocol Section 11.2, Port Data Capture Note: For information on the BANDIT products standard system management, see Chapter 10, System Management. 11.1 Simple Network Management Protocol The BANDIT can use the Simple Network Management Protocol (SNMP), a standard for network management. SNMP has several advantages that
11-2 Chapter 11: SNMP and Port Data Capture contribute to its popularity for example, it is extensible, allowing vendors to easily add network management functions. SNMP also separates the management architecture from the architecture of the hardware devices, which broadens the base of multivendor support. SNMP contains two primary elements: a manager and agents. The manager is the software on the console through which a (human) network administrator performs network management functions. An agent is the software entity that interfaces to a device being managed. Bridges, routers, and network servers are examples of managed devices. Managed devices contain managed objects. Managed objects are items such as hardware, configuration parameters, performance statistics, and so on, that directly relate to the operation of the device. These objects are arranged in a management information base (MIB). SNMP managers and agents communicate in order to view and use these MIBs. Different types of MIBs are available, including the internet standard MIB, defined in Request for Comments (RFC) documents 1212 and 1213; the remote monitoring MIB, defined in RFC 1271; and private-enterprise MIBs that vendors define for their products. Encore Networks, Inc., supports MIB II with Encore Networks proprietary extensions. The SNMP manager reads the values of the objects within a MIB and modifies the values as appropriate in other words, it manages the objects. Because SNMP is an application-layer protocol, it must rely on protocols in the lower OSI layers for other communication functions. For example, the User Datagram Protocol (UDP) transports the SNMP message through the network. IP provides network-layer functions, such as addressing for the datagram. 11.1.1 SNMP Access to the BANDIT SNMP version 1 access is available on all BANDIT models. In conformance with RFC 1294/1490, the BANDIT can be remotely accessed via SNMP over any network infrastructure, including IP, Frame Relay, SLIP, and PPP. The BANDIT supports standard MIB II variables, in addition to proprietary extensions developed by Encore Networks, Inc. Other parameters the SNMP Network Manager uses are the Get Community string (to read SNMP variables) and the Set Community string (to write SNMP variables).
Simple Network Management Protocol 11-3 Note: See Appendix D, Default Passwords, for the default values of the BANDIT device s SNMP Get Community string and Set Community string. To gain SNMP access to the BANDIT, you must configure the SNMP parameters on the BANDIT and you must configure an SNMP manager on the control terminal. See the following sections: Section 11.1.2, The BANDIT SNMP Agent Section 11.1.3, The SNMP Manager 11.1.2 The BANDIT SNMP Agent The SNMP agent is part of the BANDIT software and thus always resides in the BANDIT. You need to configure the BANDIT s SNMP settings so that the SNMP manager can manage the BANDIT. Configure the BANDIT s SNMP Get and Set communities, its SNMP Trap Table, and a default SNMP trap address. (The default SNMP trap address is the SNMP manager s IP address.) 11.1.2.1 Predefined SNMP Traps The BANDIT supports several predefined SNMP traps: Port Down. This allows the unit to send a message to the SNMP manager indicating that a physical entity, such as a cable or a CSU/DSU, is not functional. Network Down. This allows the unit to send a message to the SNMP manager indicating that the switch is not responding. DLCI Down. This allows the unit to send a message to the SNMP manager indicating that a DLCI is down. Checkstatus. This is reserved for use in testing. Memorylow. This is generated when units have insufficient memory. Physicallineup. This is sent when DTR ON has been detected by any physical port. Physicallinedown. This is sent when DTR DOWN has been detected by any physical port.
11-4 Chapter 11: SNMP and Port Data Capture FRportmgmtup. This is sent when Frame Relay management is up. If the BANDIT plays the network role in the Frame Relay connection, this means that the port starts responding to polls. If the BANDIT plays the user role in the Frame Relay connection, this means that the port begins receiving responses to polls. (The user role is always sending polls across the Frame Relay network.) FRportmgmtdown. This is sent when Frame Relay management is down. If the BANDIT plays the network role in the Frame Relay connection, this means that the port stops responding to polls. If the BANDIT plays the user role in the Frame Relay connection, this means that the port stops receiving responses to polls. FRdlciup. This is sent when a DLCI is active, when the previous status was new or DLCIDown. FRdlcidown. This is sent when a DLCI is inactive, when the previous status was new or DLCIUp. 11.1.2.2 SNMP Configuration in the BANDIT Note: This procedure must be performed via the direct connection between the BANDIT device and the local management console. 1 On the BANDIT s Main Menu, select System Administration. On the System Administration menu, select SNMP Configuration. The following menu is displayed. This menu sets passwords (i.e., a Get Community string and a Set Community string) for SNMP management. This menu also configures trap addresses (in the SNMP Trap Table) and sets a default trap address. 1) SNMP Get Community String : ****** 2) SNMP Set Community String : ****** 3) SNMP Trap Default Addr : 0.0.0.0 4) SNMP Trap Table Enter Choice:
Simple Network Management Protocol 11-5 Note: See Appendix D, Default Passwords, for the BANDIT device s SNMP Get and Set Community Strings. 2 Select Get Community String. Note: The Get string lets you view (read) the remote device s configuration. The following prompt is displayed: Define SNMP Get Community String: a Enter the Get community string. 3 Select Set Community String. Note: The Set string lets you modify (write) the remote device s configuration. The following prompt is displayed: Define SNMP Set Community String: a Enter the Set community string. 4 Select SNMP Trap Default Addr to set the default trap address. The following prompt is displayed:
11-6 Chapter 11: SNMP and Port Data Capture Enter SNMP Trap Default Address (N.N.N.N): a Enter the IP address of the terminal that runs the SNMP manager, and press Enter. 5 Select SNMP Trap Table to record up to five trap addresses. The following prompt is displayed: Enter Trap Address (N.N.N.N): a Enter a trap address and press Enter. A prompt for the next table entry appears. 6 You can continue entering addresses, or you can press Escape to return to the SNMP menu. 7 When you have finishing configuring the BANDIT, Write (save) the configuration and Reset the BANDIT. See the following sections: Section 3.3.7, Write Configuration Section 3.3.8, Reset Unit 8 If you have not yet done so, configure the SNMP manager on your control terminal. 11.1.3 The SNMP Manager To use an SNMP manager, you must configure the manager to use the Get and Set string that match those configured in the BANDIT. In addition, you must compile the SNMP manager s MIBs. 11.1.3.1 MIB Compilation Before you can use an SNMP manager to communicate with a device s SNMP agent, you must compile the manager s MIBs. MIBs must be
Simple Network Management Protocol 11-7 compiled in a specific order. Follow the instructions in the SNMP manager s user guide to organize and compile the MIBs. Note: To receive the Encore Networks proprietary MIBs, contact your Encore Networks representative. The order for compiling the Encore Networks MIBs is easy; just compile the Encore Networks MIB files in alphabetic order. (Private MIBs from other organizations do not necessarily follow alphabetic order when compiling.) Figure 11-1 through Figure 11-3 provide one example of looking at the private MIBs available on the SNMP Manager. (This example uses Castle Rock Computing s SNMPc, a Windows-based SNMP manager.) Figure 11-1. Selecting SNMP MIB Browser
11-8 Chapter 11: SNMP and Port Data Capture Figure 11-2. SNMP MIBs Directory Figure 11-3. SNMP MIBs Subdirectory PRIVATE, Expanded
Simple Network Management Protocol 11-9 11.1.3.2 Encore Networks MIB Extensions In addition to the standard MIBs in MIB II, the BANDIT uses proprietary MIB extensions from Encore Networks, Inc. The BANDIT uses the following proprietary MIB file: Fc.mib This file is divided into three subfiles: Fc_fastc.mib Fc_port.mib Fc_stats.mib The Fc_fastc.mib file is further divided into three groups: Registration Group. The Registration group contains only the Object Identifiers for all products. Temporary Group. The Temporary group contains experimental MIB variables not yet released. Product Group. The Product group comprises two subgroups: - The snmpagent subgroup contains several subgroups, described below. The snmpagent subgroup contains all SNMP-specific parameters. SNMP variables match the menu parameters and ranges used for unit configuration. The snmpagent subgroup consists of the following files: snmpmibversion snmpagentipaddr snmpagentname snmpagentsetcommunity snmpagentgetcommunity snmpagentdefaulttrapipaddr snmpagenttrapsendtable - The FrameRelay subgroup contains another subgroup called fsfrad. The fsfrad subgroup contains all SNMP-specific parameters. Table 11-1 lists the fsfrad subgroups and their component subgroups.
11-10 Chapter 11: SNMP and Port Data Capture Note: The fs at the beginning of these MIBs represents the BANDIT. The BANDIT parameters have up to 30 virtual logical ports, from 0 to 29. Table 11-1. fsfrad subgroups (1 of 3) fsfrad Subgroup fsgeneralparms Component Subgroups fsreloadfactoryvalues, fsresetunit, fssavetononvolatile, FsFirmwareVersion, fsparammodstatus, fsclearallstats, fsclocksource, fsactivecoderegion, fssoftwareversion, fsmacaddr, fsdatabase, fsactivedatabase, fsdatabasetobeused, fscleardatabase, fssystemone, fsnetworkloader, fshostipaddr, fscodefilename, fsloadtimeout, fsregion1priority, fsregion2priority, fsactivedatabase, fseraseinactiveregion, fsinitdownload, fsnetloadersectortable, fscsudsuspeed, fsdistributedsystem, fsfradrole, fsfradboardtable, fsremotelogging, fsipfilteringremotelogstatus, fsipfilteringremotelogaddr, fsipfilteringremotelogfac, fscopyconfig, fslocaloctype, fslocaloadmethod, fslocatftpseraddr, fslocatftpfilename, fslocbloctype, fslocbloadmethod, fslocbtftpseraddr, fslocbtftpfilename, fsinitcopyatob, fsinitcopybtoa, fsinitcopyactionstatus
Simple Network Management Protocol 11-11 Table 11-1. fsfrad subgroups (2 of 3) fsfrad Subgroup fsrouting fsstats fst1dsuconfig Component Subgroups fsiprouting, fsiproutingmode, fsipstatisrouting, fsipdefaultrouter, fsiptodlcitable, fsipripipframepri, fsipripipv2passwed, fsipripipdynlinksupport, fsipripacclist1action, fsipripacclist2action, fsipripacclist3action, fsipripacclist4action, fsipripacclist5action, fsipripacclist1table, fsipripacclist2action, fsipripacclist3action, fsipripacclist4action, fsipripacclist5action, fsipripinterfacetable, fsipripstatictable, fsiprippacketpri, fsipbootpaddress, fsipnametable, fsipfiltering, fsipfilteringenable, fsipfilteringremotelog, fsipfilteringtable, fsippriority, fsipprienable, fsippridefpriority, fsippritable, fsipdhcp, fsipdhcpprimaryaddr, fsipdhcpsecondaryaddr, fsipnat, fsipnatcfg1natstatus, fsipnatcfg1ipmasmode, fsipnatcfg1natipmasaddr, fsipnatcfg1pmasaddr, fsipnatcfg1remotelog, fsipnatcfg1statictable, fsipnatcfg2natstatus, fsipnatcfg2ipmasmode, fsipnatcfg2natipmasaddr, fsipnatcfgremotelog, fsipnatcfg2statictable, fsipxrouting, fsipxroutingmethod, fsipxencapsulationmethos, fsipxpassthrugptname, fsipmframerelaypri, fsipmrippacketpri, fsipxsappacketpri, fsipxwanflag, fsipxprimarynetwork, fsipxroutername, fsipxnetworksize, fsipxroutetable, fsipxtableentry, FsIpxTableEntry, fsipxindex, fsipxnetnum, fsipxpri, fsipxgptname, fsipxsapmode, fsipxstatus, fsframerelayrouting, FsFrameRelayRoutingTable, fssna, fsx25newglob, FsX25NewGlobSwEntry FC_STATS.MIB: fsframerelaystats, fsasyncencapsulationstats, fsbitsyncencapsulationstats, fsslipstats, fsriproutingstats, fsasyncburosemulationstats, fssyncburosemulationstats, fssdlcroutingstats, fsbytesyncencapsulationstats, fstelnetterminalstats, fsipxstats, fsalcstats, fstokenstats, fsetherstats, fsipstats, fsicmpstats, fsudpstats, fstcpstats, fssnmpstats, fsnetloaderstats, fsprioritystats, fssdlc2stats, fsllcstats, fssnaswstats, fst1dsustats, fse1dsustats, fsx25newstats, fsxpadstats, fsisdnstats, fsipfilteringstats, fsnewpppstats, fsmlpstats fst1dsuframeformat, fst1dsulinecode, fst1dsubitstuffing, fst1dsulinebuildout, fst1dsuclock, fst1dsulineloopback, fst1dsutimeslotdatarate, fst1dsutimeslots, fst1dsutimeslotdatatype, fst1dsuyellowalarm, fst1dsuloopbacklocalanalog, fst1dsuloopbacklocaldigit, fst1dsuloopbackremoteanalog, fst1dsuloopbackremotedigit
11-12 Chapter 11: SNMP and Port Data Capture Table 11-1. fsfrad subgroups (3 of 3) fsfrad Subgroup fse1dsuconfig fsgpt fsisdnconfig fsextdialupdev fsportprotocol Component Subgroups fse1dsuframeformat, fse1dsucrc, fse1dsuclock, fse1dsulineloopback, fse1dsutimeslots, fse1dsudatatype, fse1dsudisframe, fse1dsuaistrans fsgpttable, FsGPTEntry, fsgptentry, fsgptindex, fsgptpathname, fsgptpathtype, fsgptport, fsgptdlcinum, fsgptbackuppathname, fsgptcallingaddress, fsgptcalledaddress, fsgptpvcnumber, fsgptadminstatus fsisdnenable, fsisdnlocalphel, fsisdnspid1, fsisdnlocalphe2, fsisdnspid2, fsisdnswitchsel fsextdialupdevtable, FsExtDialupDevEntry, fsextdialupdeventry, fsextdevindex, fsextdevport, fsextdevmodemtype, fsextdevstatus FC-PORT-MI: fsportdefinition. fsframerelay, fsasyncencapsulation, fsbitsyncencapsulation, fsslip, fsasyncburosemulation, fssyncburosemulation, fssdlcroute, fsbytesyncencapsulation, fstelnetterminal, fsalc, fssdlc2, fsx25new, fsxpad, fspppnew, fspppmlink, fsethernet, fstokenring 11.1.3.3 Preparing an SNMP Connection To configure and manage the unit, connect the terminal to the Supervisor port. Press Enter to access the system. Use the BANDIT menus to configure the system. When you have finished the session, save (write) the configuration. Then select Exit from the Main Menu to terminate the session. To set up an SNMP connection, configure the following items: IP Address. This option allows the user to configure a valid IP Local Address via an async terminal. (See Section 4.2, Identifying the BANDIT in the Network.) Config port. This option allows the user to configure a port as Frame Relay, SLIP, or PPP via an async terminal, depending on the desired access method. An IP Routing table must also be configured. Ping. This option pings the configured IP Address to test connectivity. Config agent trap. This option allows the user to configure the snmpagenttrapipaddr parameter (within the snmpagent subgroup) with the IP address of the Network Manager. The unit sends SNMP traps to that address.
Simple Network Management Protocol 11-13 Modify Get/Modify Set. These options allow the user to modify the Get and/or Set Community names (parameters snmpagentgetcommunity and snmpagentsetcommunity within the snmpagent subgroup). Select protocol. This option allows the user to select the appropriate protocol under the fsportprotocol MIB. Set the SNMP parameters for the protocol. Save. This option allows the user to save all the parameters into the unit s non-volatile database by setting the fssavetononvolatile parameter (within fsgeneralparms) to Initiate. Reset. This option allows the user to reset the unit by setting the fsresetunit parameter (within fsgeneralparms) to Initiate. 11.1.3.4 Adding, Deleting, Modifying, and Viewing Table Entries You can add, delete, modify, or view any table entry in the SNMP manager. The default value for table entries is View. To add an entry, put the cursor anywhere in the table, and select the dropdown list in the Status column. Select Add. A row is added to the end of the table. To delete an entry, put the cursor in the row you want to delete, and select the dropdown list in the Status column. Select Delete. The row is removed from the table. To modify an entry, put the cursor in the row you want to modify. Select the dropdown list in the Status column and select Modify. Make the necessary changes. Note: All entries are indexed by port number, protocol name, and other variables. 11.1.3.5 Using SNMP to View the BANDIT Menus In addition to standard methods of using SNMP to manage the BANDIT, you can go through the SNMP Manager to view the BANDIT s menus. The following procedure describes how to view the BANDIT menus through the SNMP Manager.
11-14 Chapter 11: SNMP and Port Data Capture How to Use the SNMP Manager to View the BANDIT Menus Note: This example uses Castle Rock Computing s SNMPc, a Windowsbased SNMP Manager. 1 In the SNMP Manager, make sure you have configured an SNMP device for the BANDIT. (To configure the device settings, follow the instructions in the SNMP manager s instruction manual.) The BANDIT s SNMP device configuration must include the following: The BANDIT s IP address. This allows the SNMP Manager to find the BANDIT on the network. The BANDIT s Get Community string. This allows the SNMP Manager to view the BANDIT s settings. Note: The default value for the BANDIT s SNMP Get Community string is listed in Appendix D, Default Passwords. The BANDIT s Set Community string. This allows the SNMP Manager to configure and save the BANDIT s settings. Note: The default value for the BANDIT s SNMP Set Community string is listed in Appendix D, Default Passwords. 2 Select the BANDIT SNMP device. The device is highlighted (Figure 11-4).
Simple Network Management Protocol 11-15 Figure 11-4. BANDIT SNMP Device, Highlighted 3 On the top menu, or by right-clicking the SNMP device, select a Telnet connection. (On the example shown in Figure 11-5, using Castle Rock Computing s SNMPc, the menu choices are Tools, Connect Telnet.) Figure 11-5. Selecting a Telnet Connection through the SNMP Manager A Telnet window opens, asking for the remote password for the BANDIT.
11-16 Chapter 11: SNMP and Port Data Capture 4 Type the remote password and press Enter. Note: Default passwords are listed in Appendix D. The BANDIT s main menu appears (Figure 11-6). 5 Use the BANDIT menus to configure and monitor the BANDIT. Figure 11-6. BANDIT s Main Menu, Telnetted through SNMP Manager 11.1.4 Using SNMP with Port Data Capture Port Data Capture (PDC) can be used in conjunction with SNMP to enhance troubleshooting, especially when a problem is intermittent. The Encore Networks device can be programmed to send an SNMP trap under certain conditions e.g., when an intermittent problem is actually occurring. The SNMP management station can be programmed to issue a script, based on this SNMP trap, that starts a Port Data Capture to run for a predetermined amount of time e.g., 15 minutes. The network administrator can retrieve the captured data later for analysis. For details, see Section 11.2, Port Data Capture.
Port Data Capture 11-17 11.2 Port Data Capture Port Data Capture (PDC) is a powerful troubleshooting feature embedded in all of Encore Networks data products, including the BANDIT. The port trace functionality allows the unit to monitor data packets on any or all of a unit s data ports. This feature helps resolve network problems by displaying live data for the ports. PDC encompasses features to troubleshoot legacy traffic on serial interfaces and to troubleshoot IP traffic. No external test or monitoring hardware is required for monitoring data packets on the LAN, WAN, modem, serial, or expansion ports. Example: Suppose a product at a remote branch is having problems with data traffic. The remote site can notify the central office by sending an SNMP trap/alarm to an SNMP Manager. An operator at the central office can remotely access the product s menus, selecting Port Data Capture. Depending on the problem, the operator may select one or more ports to analyze the data traffic. Use of PDC from a remote site saves the cost of sending a service person carrying hardware and software to the site to troubleshoot the problem. 11.2.1 Features of Port Data Capture All ports on all BANDIT models support Port Data Capture: Ethernet LAN, WAN, and DMZ T1/E1 CSU 56k/64k DSU Serial Modem The Remote Data Unit, used with the BANDIT Plus and the VSR-1200, also supports PDC on its Ethernet port and on all 12 serial ports. PDC has the following features: The user can select the format ASCII, EBCDIC, or hexadecimal for the information the PDC displays.
11-18 Chapter 11: SNMP and Port Data Capture The captured information can be monitored live, can be captured and stored, or can be captured and sent to the central office for analysis. PDC can be set to monitor data indefinitely or for a specific time period. The default is 3 hours. The user can determine the amount of memory used to capture data. When starting a capture, the menu prompts for buffer size and capture slice. The user can accept the defaults or enter new values. The default capture slice is 64 bytes and the default buffer allocation is 75,000 bytes. The maximum allowed buffer is 3.4 Mbytes. PDC does not affect the operation of the Encore Networks product or any of its ports. PDC is passive; it requires no processing resource and runs quietly in the background. Note: The settings for Port Data Capture cannot be saved as part of the BANDIT device s configuration. How to Use the Port Data Capture Feature 1 From the Main Menu, select System Administration >> Port Data Capture. The Data Capture Port Selection and Status menu appears. Data Capture - Port selection and status ----------------------------------------- M) MODEM : OFF L) LAN : OFF W) WAN : OFF S) SERIAL : OFF Enter Choice : 2 Do one of the following: a b Press the Escape key to return to the higher menu. Select the port you wish to monitor.
Port Data Capture 11-19 The port s Capture menu, similar to the following, is displayed. The menu shown here indicates that the port s capture status is Off. Capture of : SERIAL currently OFF ---------------------------------------- 1) Start a capture 2) Stop a capture 3) Clear capture buffer 4) Display captured data 5) Dump captured data to the screen Enter Choice : 3 Do one of the following: a To return to the Data Capture Port Selection menu, press the Escape key. The Data Capture Port Selection menu appears. Go to Step 2. b To capture this port s data, select Start a Capture. The following prompts appear. Answer them as appropriate for your network, and press Enter. (Or just press Enter, without typing anything, to accept the defaults.) Enter max slice [64] : Enter max buffer [75000] : Enter Timeout value in hours [3] :
11-20 Chapter 11: SNMP and Port Data Capture After you have entered values (or accepted defaults) for the parameters, the following message appears. ** Capture started ** Then the port s Capture menu re-appears. Note that the port status indicates that capturing is in progress. Repeat Step 3. Capture of : SERIAL currently CAPTURING Total=0 ------------------------------------------------------- 1) Start a capture 2) Stop a capture 3) Clear capture buffer 4) Display captured data 5) Dump captured data to the screen Enter Choice : c If you want to stop a capture before it times out, select Stop a Capture. The following message appears, followed by the port s Capture menu, showing the port capture status as Stopped. Repeat Step 3. ** Capture stopped ** d To clear the capture buffers, and to turn off a capture session, select Clear Capture Buffer. The following message appears, followed by the port s Capture menu, showing capture status as Off. Repeat Step 3. ** Capture buffer cleared **
Port Data Capture 11-21 e To see a line-by-line display of the port data, select Display Captured Data. Go to Step 4. The menu for display mode appears. 1) Normal mode 2) Summary mode Enter mode [1] : f To see a complete display of the captured port data, select Dump Captured Data to the Screen. The format selection menu appears. Go to Step 6. Enter Choice : 5 1) ASCII format 2) EBCDIC format 3) Hexadecimal format Enter format [1] : 4 For a line-by-line display of captured data, do the following: a Select the mode you wish to view: A menu to select the format appears: 1) ASCII format 2) EBCDIC format 3) Hexadecimal format Enter format [1] : b Select the format for the display. The screen displays capture data for this port. (If there are no data, the message indicates that.) After the display, a line asks for the next line of data you wish to view.
11-22 Chapter 11: SNMP and Port Data Capture *** Capture buffer for this port is empty *** Enter [(F)irst, (N)ext, (S)pecific or (C)hange format]: 5 Do one of the following: a To stop the data display, press the Escape key. The port s Capture menu is redisplayed. Go to Step 3. b To change the display format, select Change Format. The menu for display mode appears again. Go to Step 4a. c To view a specific line, select Specific. A prompt asks for the line number. Enter line number : Type the line number and press Enter. The display continues. Repeat Step 5. d To view the first line again, select First. The display continues. Repeat Step 5. e To view the next line, select Next. The display continues. Repeat Step 5. 6 For a complete display of captured data, do the following: a Select the format for the display.
Port Data Capture 11-23 Start the file capture, press to display capture b To display the data, press the Enter key. The information is displayed on the screen. *** Capture buffer for this port is empty *** After the data have been displayed, the capture is automatically stopped. Stop the file capture Then the port s Capture menu is redisplayed. Go to Step 3. Capture of : SERIAL currently STOPPED Total=0 --------------------------------------------------------- 1) Start a capture 2) Stop a capture 3) Clear capture buffer 4) Display captured data 5) Dump captured data to the screen Enter Choice :
11-24 Chapter 11: SNMP and Port Data Capture