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Cisco SwitchProbe devices are hardware products with embedded firmware, designed to collect statistical information of an attached network segment.
Cisco SwitchProbe devices come in different models to monitor different network topologies such as Ethernet, Fast Ethernet, Fast EtherChannel, Token Ring, Wide Area Network (WAN), Asynchronous Transfer Mode (ATM), and Fiber Distributed Data Interface (FDDI).
SwitchProbe devices support Remote Monitoring1 (RMON1), Remote Monitoring2 (RMON2), and Cisco's enhanced RMON extensions. These devices provide complete protocol monitoring and decoding when used with a client equipped with protocol decode software. All models also support the MIB II system and interface groups.
Each SwitchProbe device contains specialized firmware known as agent code. The agent code is the device's intelligence. The agent code consists of a series of commands that instruct the device to examine and gather statistical information about packets or cells passed along the network segment to which the SwitchProbe device is attached. This statistical information is stored in continuous counters in the device's random access memory (RAM). You can reset the counters to zero upon command.
In addition to gathering statistics, the SwitchProbe device supports filters and packet- capture RMON1 groups so you can examine individual packets or sequences of packets to identify and isolate network problems. The SwitchProbe device also supports all RMON2 groups and can decode packets from the network layer through the application layer of the OSI model. With this feature, you can monitor traffic on the basis of network layer protocols and addresses, and monitor application-level traffic.
A typical network is equipped with multiple SwitchProbe devices, with one device connected to each individual network segment or to the Switched Port Analyzer (SPAN) port on the switch.
The SwitchProbe devices are managed and controlled from a centrally located traffic management console (using the TrafficDirector application) that is designated as the client. From the client, you can request and examine data provided by the agent you select. With Cisco SwitchProbe agents, you can have multiple active clients, allowing you to perform network diagnostic functions from multiple locations, such as from primary and secondary network management centers.
When a SwitchProbe device is connected to the network segment or to the SPAN port on a switch, you can achieve greater network visibility.
Each port on a switch typically has only mini-RMON capabilities. Mini-RMON supports four groups for monitoring network traffic—statistics, history, alarm, and events. When a SwitchProbe device is attached to a switch, you can achieve full RMON capabilities, that is RMON1 and RMON2 (see Table 1-2 and Table 1-3). This lets you manage and monitor network traffic and isolate network problems.
In manage mode, the SwitchProbe device exchanges (sends/receives) management data with an attached management station.
In monitor mode, the SwitchProbe device receives network traffic for mapping statistical information into standard RMON-based counters.
SwitchProbe devices are housed in small chassis and front-access chassis.
The SwitchProbe devices in the small chassis series measure 12 inches wide, by 13.5 inches deep, by 3 inches high (30 by 33.75 by 7.5 cm). They are housed in an external chassis which can be placed on a tabletop. The small chassis series are also referred to as the PB6 series.
The interface cards in the small chassis series are located in the back of the device. They are available in different configurations with different combinations of interface types.
The following devices are part of the small chassis series:
Ethernet and Token Ring devices are intended for use in Ethernet and Token Ring environments. A single RMON agent is standard. An optional second Local Area Network (LAN) interface, and an RMON agent to monitor the second LAN link is also available. However, Cisco Systems recommends that you configure the second interface in manage mode only.
The SwitchProbe devices in the front-access chassis measure 17 inches wide, by 16.5 inches deep, by 5.25 inches high (13.3 by 43.18 by 41.91 cm). They are housed in an external, rack-mountable large chassis for mounting in a 19-inch equipment rack. The front-access chassis is also referred to as the PB8 series.
Unlike the small chassis where the interfaces are accessed from the back of the device, the interfaces in the front-access chassis are accessed from the front of the device.
The front-access devices include an Ethernet interface for connection to the network management software.
The following devices are part of the front-access chassis series:
For more information about the SwitchProbe devices, see "Physical Description."
Table 1-1 provides a brief description of the small chassis and the front-access chassis series and lists the SwitchProbe devices under each of these chassis.
| Chassis | Description | SwitchProbe Devices |
|---|---|---|
Dimensions (H x W x D)— Can be placed on a table-top. Interfaces are accessed from the back of the device. |
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Dimensions (H x W x D)— Can be mounted in a standard 19-inch equipment rack. Interfaces are accessed from the front of the device. |
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Cisco Systems recommends using the following software releases:
Cisco SwitchProbe devices are based upon two widely accepted industry standards:
Other emerging standards are supported to allow you to simultaneously monitor multiple network segments from various topologies using the TrafficDirector application. These emerging standards include:
The following are Cisco proprietary standards:
Although the RMON-MIB standard does not specifically address Fast Ethernet, ATM, FDDI, and WAN media, Cisco Systems has adapted its basic monitoring and diagnostic functions to meet requirements for managing these essential links. For more information, see "Shadow MIB Implementations."
The TrafficDirector application uses statistics based on the following RMON standard groups:
The TrafficDirector application can interpret and manipulate both RMON1 and RMON2 data; therefore, you can monitor all seven layers of the OSI model.
The RMON1 standard was developed under the guidance of the Internet Engineering Task Force (IETF) as an extension of its work in the development of the SNMP protocol. Using this standard, independent developers can design and develop monitoring equipment that interoperates and provides a standards base compatible with the widest range of network needs. Because these groups have been defined, developers can implement products that include any or all of the nine groups for Ethernet or the ten groups for Token Ring. Some developers can supplement the defined groups with private MIBs that extend the functionality beyond the existing standard.
The basic 10 RMON1 groups are summarized in Table 1-2.
| This Group... | Provides This Functionality |
|---|---|
Counters for packets, octets, broadcasts, errors, and other statistics. | |
A historical representation of the statistics counters, based on user-defined sample intervals. (A mini-RMON group.) | |
A table of statistical counters for each host. | |
A user-defined subset (TopN) of the hosts, sorted by a statistical counter. By aggregating this data at the agent and returning only the results, management traffic is minimized. | |
Traffic and errors between pairs of hosts. | |
Thresholds, defined for any statistic, that return a trap to the management software. Alarms are the thresholds. (A mini-RMON group.) | |
SNMP traps based on the alarms group thresholds; also tracks alarms over time. (A mini-RMON group.) | |
Criteria for selecting traffic for packet capture. | |
Stores network traffic to be uploaded later in to the management software. | |
Token Ring specific information, including ring order and source routing. |
SwitchProbe devices support the following:
RMON2 group provides network-layer and upper-layer monitoring capabilities using major protocol domains as described in Table 1-3.
| This Group... | Provides This Functionality |
|---|---|
Management stations may query RMON SwitchProbe devices to learn from which domains they are collecting information. | |
Defines how much traffic is distributed across the various protocols on the network based on monitoring at the RMON SwitchProbe device. | |
AddressMap | A list developed by the RMON SwitchProbe device that matches host network addresses to MAC addresses. |
Network-layer host statistics. | |
N1Matrix | Network-layer host pair conversation statistics. |
Application-layer host statistics. | |
A1Matrix | Application-layer host pair conversation statistics. |
User-specified logging capability. | |
Standards for SwitchProbe device configuration, such as a method to define the current date and time settings, and reset controls, including running, warmBoot, and coldBoot states. |
Enhanced RMON extensions include the software options shown in Table 1-4.
| This Software Option... | Provides This Functionality |
|---|---|
Monitors critical network resources. | |
Provides distributed monitoring of the router backbone. | |
Collects ART1 statistics. | |
Provides analysis for aggregating traffic of separate full- duplex Fast Ethernet segments into one full-duplex trunk. |
| 1Application Response Time |
To activate these software options, you must purchase a password by contacting your Cisco Systems' sales representative. For more information about these options, see "Software Options."
In addition to the software options described in Table 1-4, Cisco's enhanced RMON extensions also include the following functionality:
While you can only use the enhanced RMON functionality using the TrafficDirector application, SwitchProbe default groups RMON2 agent support provides compatibility with third-party management software. You can configure the SwitchProbe agent to install a number of these domains automatically by enabling default groups.
Default groups allow the SwitchProbe device to initialize as an RMON2 agent. When default groups are enabled and the SwitchProbe device is reset or powered on, the agent automatically installs the major protocol domains. For more information, see "Configuring the Default Domain" in ""Configuration."
SwitchProbe agents support router discovery. Network routers can be configured to send out periodic router advertisements used by the agent to configure its default gateway address. If the agent does not receive any router advertisements for the duration specified in the last router advertisement message, the agent displays a message on the console. You can enable or disable this feature using the agent_options parameter of the agent command-line mode. For more information, see "Command-Line Mode."
The SwitchProbe agents also feature a variety of routing options, including the ability to establish both semipermanent and permanent routes for individual IP addresses or subnets. A trap routing function also permits trap messages from other SNMP agents to be routed through the SLIP interface to alternative network management locations. These functions are often useful in implementing third-party maintenance operations at remote network management centers. For more information, see "Advanced Features."
SwitchProbe agents support the SNMP community mechanism. The agent has read and write community strings that can be configured. Any management station that tries to read or write to the agent must use community strings that match those set on the agent. To read any data from the agent, the read community strings must match. To change any settings on the agent, the write community strings must match. For more information about read and write community strings, see "Configuration."
An access list that can be configured gives you enhanced security. The access list uses the IP address of the management station requesting access to determine what read and write privileges to grant. For more information about security, see "Advanced Features."
The local and remote SwitchProbe login consoles are password-protected. There are two login types:
Posted: Wed Oct 2 08:25:21 PDT 2002
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