Snmp management software cisco

A VPN is a network that provides high connectivity transfers on a shared system with the same usage guidelines as a private network. A VRF consists of an IP routing table, a derived Cisco Express Forwarding table, and guidelines and routing protocol parameters that control the information that is included in the routing table.

With this configuration, service providers can provide network management services to their customers, so customers can manage all user VPN devices. One of the identifiers most commonly used in SNMP-based network management applications is the interface index IfIndex value. IfIndex is a unique identifying number associated with a physical or logical interface; as far as most software is concerned, the ifIndex is the name of the interface.

Although there is no requirement in the relevant RFCs that the correspondence between particular ifIndex values and their interfaces be maintained across reboots, applications such as device inventory, billing, and fault detection increasingly depend on the maintenance of this correspondence.

This feature adds support for an ifIndex value that can persist across reboots, allowing users to avoid the workarounds previously required for consistent interface identification. It is currently possible to poll the device at regular intervals to correlate the interfaces to the ifIndex, but it is not practical to poll this interface constantly.

If this data is not correlated constantly, however, the data may be made invalid because of a reboot or the insertion of a new card into the device in between polls. Therefore, ifIndex persistence is the only way to guarantee data integrity. IfIndex persistence means that the mapping between the ifDescr object values and the ifIndex object values generated from the IF-MIB will be retained across reboots.

The Interface Index Persistence feature allows for greater accuracy when collecting and processing network management data by uniquely identifying input and output interfaces for traffic flows and SNMP statistics. Relating each interface to a known entity such as an ISP customer allows network management data to be more effectively utilized. Network data is increasingly being used worldwide for usage-based billing, network planning, policy enforcement, and trend analysis.

The ifIndex information is used to identify input and output interfaces for traffic flows and SNMP statistics. Inability to reliably relate each interface to a known entity, such as a customer, invalidates the data. When the notifications are triggered through events, the NMS does not need to constantly poll managed devices to track changes. By allowing the SNMP notifications to take place only when a specified condition is met, the Event MIB reduces the load on affected devices and improves the scalability of network management solutions.

The Event MIB operates based on event, object lists configured for the event, event action, trigger, and trigger test. The event table defines the activities to be performed when an event is triggered. These activities include sending a notification and setting a MIB object. The event table has supplementary tables for additional objects that are configured according to event action.

If the event action is set to notification, notifications are sent out whenever the object configured for that event is modified. The object table lists objects that can be added to notifications based on trigger, trigger test type, or the event that sends a notification.

The Event MIB allows wildcarding, which enables you to monitor multiple instances of an object. To specify a group of object identifiers, you can use the wildcard option. The trigger table defines conditions to trigger events. The trigger table lists the objects to be monitored and associates each trigger with an event. An event occurs when a trigger is activated. This trigger entry specifies the object identifier of the object to be monitored.

The Event MIB process checks the state of the monitored object at specified intervals. The trigger table has supplementary tables for additional objects that are configured based on the type of test performed for a trigger.

For each trigger entry type such as existence, threshold, or Boolean, the corresponding tables existence, threshold, and Boolean tables are populated with the information required to perform the test. The Event MIB allows you to set event triggers based on existence, threshold, and Boolean trigger types. When the specified test on an object returns a value of true , the trigger is activated. You can configure the Event MIB to send out notifications to the interested host when a trigger is activated.

The Expression MIB allows you to create expressions based on a combination of objects. The expressions are evaluated according to the sampling method. The Expression MIB supports the following types of object sampling:. If there are no delta or change values in an expression, the expression is evaluated when a requester attempts to read the value of expression. In this case, all requesters get a newly calculated value.

For expressions with delta or change values, evaluation is performed for every sampling. In this case, requesters get the value as of the last sample period. Absolute sampling uses the value of the MIB object during sampling. Delta sampling is used for expressions with counters that are identified based on delta difference from one sample to the next.

Delta sampling requires the application to do continuous sampling, because it uses the value of the last sample. Changed sampling uses the changed value of the object since the last sample. Systems that support SNMP often need a mechanism for recording notification information. This mechanism protects against notifications being lost because they exceeded retransmission limits.

The SNMP Notification Logging feature adds Cisco command line interface commands to change the size of the notification log, to set the global ageout value for the log, and to display logging summaries at the command line. You can globally enable or disable authenticationFailure, linkUp, linkDown, warmStart, and coldStart traps or informs individually. Note that linkUp and linkDown notifications are enabled by default on specific interfaces but will not be sent unless they are enabled globally.

There is no specific command that you use to enable SNMP. The first snmp-server command that you enter enables the supported versions of SNMP. All other configurations are optional. You can set the system contact, location, and serial number of the SNMP agent so that these descriptions can be accessed through the configuration file. Although the configuration steps described in this section are optional, configuring the basic information is recommended because it may be useful when troubleshooting your configuration.

In addition, the first snmp-server command that you issue enables SNMP on the device. Perform the following tasks when configuring SNMP version 1 or version 2.

You can use a predefined view or create your own view. If you are using a predefined view or no view at all, skip this task. You can use this command multiple times to create the same view record. If a view record for the same OID value is created multiple times, the latest entry of the object identifier takes precedence. The community string acts like a password to regulate access to the agent on the device. Optionally, you can specify one or more of the following characteristics associated with the string:.

An access list of IP addresses of the SNMP managers that are permitted to use the community string to gain access to the agent. By default, the above ip access list configuration have permit "any any" so there is no issue with snmp polling.

Read and write or read-only permission for the MIB objects accessible to the community. SNMP traps are unreliable because the receiver does not send acknowledgments when it receives traps. The sender does not know if the traps were received.

If the sender never receives the response, the inform can be sent again. Compared to traps, informs consume more resources in the agent and in the network. Also, traps are sent only once; an inform may be sent several times. The retries increase traffic and overhead on the network. If you do not enter a snmp-server host command, no notifications are sent. To configure the device to send SNMP notifications, you must enter at least one snmp-server host command.

If you enter the command without keywords, all trap types are enabled for the host. To enable multiple hosts, you must issue a separate snmp-server host command for each host. You can specify multiple notification types in the command for each host. When multiple snmp-server host commands are given for the same host and type of notification, each succeeding command overwrites the previous command.

Only the last snmp-server host command will be in effect. For example, if you enter an snmp-server host inform command for a host and then enter another snmp-server host inform command for the same host, the second command replaces the first. The snmp-server host command is used in conjunction with the snmp-server enable command. Use the snmp-server enable command to specify which SNMP notifications are sent globally. For a host to receive most notifications, at least one snmp-server enable command and the snmp-server host command for that host must be enabled.

Some notification types cannot be controlled with the snmp-server enable command. For example, some notification types are always enabled and others are enabled by a different command.

For example, the linkUpDown notifications are controlled by the snmp trap link-status command. These notification types do not require an snmp-server enable command. For example, the envmon notification type is available only if the environmental monitor is part of the system. To see what notification types are available on your system, use the command help? SNMPv3 is a security model.

A security model is an authentication strategy that is set up for a user and the group in which the user resides. No default values exist for authentication or privacy algorithms when you configure the snmp-server group command. Also, no default passwords exist. For information about specifying a MD5 password, see the documentation for the snmp-server user command. Configures the SNMP server group to enable authentication for members of a specified named access list. To configure a remote user, specify the IP address or port number for the remote SNMP agent of the device where the user resides.

Also, before you configure remote users for a particular agent, configure the SNMP engine ID, using the snmp-server engineID command with the remote option. If the remote engine ID is not configured first, the configuration command will fail. For the privpassword and auth-password arguments, the minimum length is one character; the recommended length is at least eight characters, and should include both letters and numbers.

For informs, the authoritative SNMP agent is the remote agent. No default values exist for authentication or privacy algorithms when you configure the command. The minimum length for a password is one character, although we recommend using at least eight characters for security.

If you forget a password, you cannot recover it and will need to reconfigure the user. You can specify either a plain text password or a localized MD5 digest. If you have the localized MD5 or SHA digest, you can specify that string instead of the plain text password. The digest should be formatted as aa:bb:cc:dd where aa, bb, and cc are hexadecimal values.

Also, the digest should be exactly 16 octets in length. The following example shows the information about the configured characteristics of the SNMP user If you are configuring a user using AES encryption, ensure that you use a combination of variables which does not exceed characters for user config to work. Perform this task to enable the SNMP manager process and to set the session timeout value.

Using SNMP packets, a network management tool can send messages to users on virtual terminals and on the console. This facility operates in a similar fashion to the send EXEC command; however, the SNMP request that causes the message to be issued to the users also specifies the action to be taken after the message is delivered.

One possible action is a shutdown request. After a system is shut down, typically it is reloaded. Because the ability to cause a reload from the network is a powerful feature, it is protected by the snmp-server system-shutdown global configuration command.

If you do not issue this command, the shutdown mechanism is not enabled. You can define the maximum packet size permitted when the SNMP agent is receiving a request or generating a reply. Limiting the use of TFTP servers in this way conserves system resources and centralizes the operation for manageability.

To configure a device to send SNMP traps or informs, perform the tasks described in the following sections:. Many snmp-server commands use the keyword traps in their command syntax. Unless there is an option within the command to specify either traps or informs, the keyword traps should be taken to mean traps, informs, or both.

Use the snmp-server host command to specify whether you want SNMP notifications to be sent as traps or informs. This won't have any impact on the system. The threshohld limit can be set to any value between to ms. To disable the response threshold limit, use the no snmp monitor response command. You cannot configure a remote user for an address without first configuring the engine ID for that remote host. This restriction is imposed in the design of these commands; if you try to configure the user before the host, you will receive a warning message and the command will not be executed.

Use the snmp-server engineid remote command to specify the engine ID for a remote host. The snmp-server host command specifies which hosts will receive SNMP notifications, and whether you want the notifications sent as traps or informs.

Enables sending of traps or informs and specifies the type of notifications to be sent. If a notification-type is not specified, all supported notification are enabled on the device. To discover which notifications are available on your device, enter the snmp-server enable traps? You can enable Syslog traps using the snmp-server enable traps syslog command. After you enable Syslog traps, you have to specify the trap message severity.

Use the logging snmp-trap command to specify the trap level. By default, the command enables severity 0 to 4. If you want to enable all the severities, use the following form of the command:. Note that, along with the above configuration, Syslog history command also needs to be applied. Without this configuration, Syslog traps are not sent. You can specify a value other than the default for the source interface, message packet queue length for each host, or retransmission interval.

Perform this task to change notification operation values as needed. Enter your password if prompted. Establishes the message queue length for each notification. This example shows the queue length set to 50 entries. Defines how often to resend notifications on the retransmission queue.

Configures inform-specific operation values. This example sets the maximum number of times to resend an inform, the number of seconds to wait for an acknowledgment before resending, and the maximum number of informs waiting for acknowledgments at any one time. Perform this task to enable the authenticationFailure, linkUp, linkDown, warmStart, and coldStart notification types. When used without any of the optional keywords, enables authenticationFailure, linkUp, linkDown, warmStart, and coldStart traps.

When used with keywords, enables only the trap types specified. For example, to globally enable only linkUp and linkDown SNMP traps or informs for all interfaces, use the snmp-server enable traps snmp linkup linkdown form of this command. To enable SNMP traps for individual interfaces such as Dialer, use the snmp trap link-status permit duplicates command in interface configuration mode.

For example, to enter dialer interface configuration mode, enter the interface type as dialer. The following example shows the status of linkup and linkdown traps for all interfaces configured for the system:. Perform this task to configure SNMP notification log options.

These options allow you to control the log size and timing values. The SNMP log can become very large and long, if left unmodified. Sets the maximum amount of time for which the SNMP notification log entries remain in the system memory. In this example, the system is configured to delete entries in the SNMP notification log that were logged more than 20 minutes ago.

The display of Interface Indexes lets advanced users of SNMP view information about the interface registrations directly on a managed agent. An external NMS is not required. Configuration of Long Alias Names for the interfaces lets users configure the ifAlias the object defined in the MIB whose length is restricted to 64 up to bytes. Use Cisco Feature Navigator to find information about platform support and software image support. Perform this task to configure the IF-MIB to retain ifAlias values of longer than 64 characters and to configure the ifAlias values for an interface.

The description for interfaces also appears in the output from the more system:running config privileged EXEC mode command. If the ifAlias values are not configured using the snmp ifmib ifalias long command, the ifAlias description will be restricted to 64 characters. Cisco pxGrid provides a unified framework that enabl Created by meddane on AM.

Ask a Question. Find more resources. Blogs Security Blogs Security News. Project Gallery. New Community Member Guide. Related support document topics. Recognize Your Peers. Spotlight Award Nomination. Content for Community-Ad. Datadog is available on a day free trial. ManageEngine OpManager is another network monitoring tool that can monitor devices from various vendors including Cisco.

Like Solarwinds NPM, it also supports features like automatic network discovery, availability and performance monitoring, and various reporting capabilities. With additional licenses, network traffic analysis and configuration management can also be enabled. One of the really cool things about ManageEngine OpManager is its customizable dashboard feature, allowing you to configure the user interface with exactly what you will like to see.

It can be installed on Windows and Linux operating systems. There is a live demo of OpManager on their site to really get a feel for what it looks like and how it works. We highly recommend you can also download a free day trial or a free-forever edition that allows you to monitor 10 devices with limited functionality. WhatsUp Gold is one of the network monitoring tools that have been around for a long time even though interest in the product went down a couple of years ago.

WhatsUp Gold uses Point-based licensing where different monitored elements are assigned points e. It supports the following features:. The Cisco Network Assistant supports up to 80 devices and therefore, is targeted at small to medium sized businesses. The fact that it is free you only need to login to download it is also a bit surprising knowing that Cisco generally does not do free things. It can be installed on Windows and Mac operating systems. Network Monitoring is a very important aspect of managing a network because not only can it alert you when something goes wrong, it can also help during troubleshooting and for network planning.

The choice of the tool you use to monitor your Cisco devices will depend on factors like cost, complexity and robustness. We recommend donwloading their 30 Day Unlimited Trial and starting monitoring within 10 minutes of installing. They have a Great Auto Discovery feature that will assist you in scanning your network for Cisco Devices and automatically add them to your inventory.

If you're looking for other options, PRTG Network Monitor is an all-in-one solution and might be less expensive for your network if you are on a budget. The Cisco Network Assistant is more fitting as a network management tool even though it also provide some monitoring capabilities not at the same level as the other tools mentioned.

All the tools we discussed in this article are commercially available even though Cisco Network Assistant is free. When compared against open source network monitoring tools, these commercial software have the advantage of being to a more probable extent supported and updated by their developers. These commercial vendors may also be able to provide expert engineers to assist with issues and troubleshooting if they arise.

Installs on Windows Server. Start a day free trial. Runs on Windows Server. Datadog Network Monitoring A cloud-based subscription monitoring tool that offers a special Cisco Meraki integration that adds on to an SNMP-based network device monitor. Installs on Windows Server and Linux WhatsUp Gold A network performance monitor that includes SNMP-based device supervision and can be extended with paid add-ons to monitor network traffic, servers, and applications.

Cisco Network Assistant A free tool provided by Cisco to monitor its range of products, including switches, routers, wireless APs, IP phones, and firewalls. Runs on Windows and macOS. Other reasons include: Monitoring bandwidth Usage : Is your ISP being sneaky or is a worm is eating up your bandwidth?

Performance monitoring: Monitoring can help you determine if your network is performing optimally or if there is network congestion e. Intrusion Detection: If you keep getting failed login attempts, it could mean someone is trying to break into your network. Also, sudden spikes in network traffic can indicate an attack. You will only detect these attacks if you are monitoring your network.