articulating a particular point of view. Chetan Bhagat's books do both and more. - A.R. Rahman, in TIME magazine, on Che. [3] CCNP TSHOOT Quick Reference CHAPTER 1 by Brent Stewart Maintenance Chapter 1 Maintenance Maintenance might seem separate from the . This book is designed to provide information about the CCNP TSHOOT Exam ( Exam ) for the. CCNP Routing and Switching certification. Every effort has.

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CCNP TSHOOT Lab Uploaded by Download as PDF or read online from Scribd. Flag for .. PaloAlto Training print pdf. Uploaded. CCNP TSHOOT OFFICIAL CERTIFICATION GUIDE wp1-nyc. ccnp tshoot pdf. Search for and download any torrent from the. ccnp tshoot pdf. Troubleshooting and Maintaining Cisco IP Networks ( TSHOOT) Foundation Learning Guide: Foundation learning for the CCNP.

Start with the OSI physical layer and work up. Start at the network layer and follow the evidence, developing specific tests of each hypothesis. Understand the order of operations within each device to do this. Compare the configuration to an older version or to that of a similar device. Diff and WinDiff are tools that make this comparison easy.

Swap components to see if the problem moves with a device. Two troubleshooting tactics need special mention. Most technicians build up a reservoir of experience, which gives them an intuition about the solution to a given problem. This thinking is a logical error: Sometimes this does provide a clue, but large networks have many things happening contemporaneously every second.

This troubleshooting method can easily provide a false lead. The Troubleshooting Method Troubleshooting a network falls into a series of steps that mirror the scientific method. The first step in troubleshooting is to define the problem.

Always start the troubleshooting process by gathering a detailed description of the problem. Ask questions to gather details, such as the names and locations of affected devices.

One good way to gather details is to ask about how the problem can be duplicated. What is the scope? What other devices or locations are affected? When did it start? How can you test the problem? As information is gathered, one or more theories might begin to form. Develop tests that confirm or refute the theories, and work to find the root cause.

Tests can be as simple as pings or as complex as implementing a configuration change; the tests should be aimed at separating valid theories. When the testing process is complete, take a moment to consider the results. Do the results suggest a configuration or hardware change? Is the problem resolved? If not, reconsider the problem description and the original hypothesis.

Either the problem was not completely and accurately described, or the hypothesis was incorrect and needs to be revisited. The state of the network and the problem resolution need to be communicated, and documentation might need to be updated. Past these obvious steps, consider whether the problem found can be in other parts of the network. If the problem were in the configuration, think through the configuration template used in your network and determine if the fix needs to be repeated preemptively on other devices.

The important points here are to work logically and methodically, and to view each problem as an opportunity to perfect the larger network. Integrating Troubleshooting into Maintenance Every interaction with the network is an opportunity to learn. Smart organizations capture information learned to solve similar problems and to help understand the network in the future. Change control and documentation are the two principal ways that feedback from network changes is incorporated into the maintenance cycle, as shown in Figure Troubleshooting identifies the corrective action to upgrade or repair the network.

Throughout these processes, a regular communication with end users is critical to understand the problem and to gather feedback on the solution. Communication with end users, within the team, and with management is pervasive throughout the cycle. The change-control process is a formal communication process for requesting and receiving permission.

Change control provides an opportunity for management and peers to be aware and consent to the proposed change. The change process encourages the network technician to take a deliberate and thoughtful approach.

Finally, the change process creates a record of the change that can be incorporated in documentation. After a change is made and an issue is resolved, updating documentation must be seen as a part of the clean-up process. Most organizations have records including IPs, inventory, configurations, and topology; changes need to be added to these records.

If the change is sufficiently broad, it might also need to be incorporated into standards and templates so that other devices can be preemptively upgraded. As records and standards change, team members need to be educated on the changes.

A number of tools can compile baseline data and monitor the network continuously. A baseline is a reading of the critical parameters of the network such as latency and utilization over a period of time. The baseline serves as a record of normal behavior to help identify how performance has changed. Updating baseline information is part of the documentation process. Think about troubleshooting as a holistic process. Approach each issue with a rational evidence-based philosophy, make thoughtful changes, and communicate with all the invested groups often.

Understanding the capabilities of the operating system and how to use them effectively can reduce time-to-repair and the stress of a network outage. Many people are not familiar with the filtering techniques that enable a troubleshooter to quickly focus. Some of these filters are command-specific. Consider show ip route, which is a familiar command.

When used, this command shows a complete routing table as shown here: Foard-rtr01 show ip route Codes: One way to summarize this information is to ask for a summary using show ip route summary.

Specifying an address, mask, and the keyword longer-prefixes asks for anything that matches the prefix or any routes contained within the prefix. The following example shows all the more-specific routes contained within the Foard-rtr01 show ip route Generic filters can also be applied to all show commands. Show process cpu, which might be used to look for runaway processes, can be used as an example. First, an example portion of output is shown: Foard-rtr01 show process cpu CPU utilization for five seconds: Output is matched against a regular expression.

Following is a table of common regular expression characters. Any character Ethernet. Foard-rtr01 show process cpu include IP Input 87 58 0. In the following example, piping to begin starts the output at the telnet ports. This is a lot easier that using the space key to work through a large configuration: Foard-rtr01 show running-configuration begin vty line vty 0 4 exec-timeout 20 0 password 7 CD logging synchronous transport input ssh transport output telnet ssh line vty 5 15 exec-timeout 20 0 password 7 CD logging synchronous transport input ssh transport output telnet ssh!

Piping output can be a great way to focus on relevant details, but show running-configuration section is a lot to type, particularly repeatedly. The alias command can make this easier. In configuration mode, create a shortened version of a command as shown next. Type srs vty to see the same output as the example. In the preceding example, piping to begin also includes all the text after the part of interest. Piping to section shows the indented commands under a line that matches the regular expression.

In the following example, the sections found under the keyword vty are shown: Foard-rtr01 show running-config section vty line vty 0 4 exec-timeout 20 0 password 7 CD logging synchronous transport input ssh transport output telnet ssh line vty 5 15 exec-timeout 20 0 password 7 B1ED2B2C2B logging synchronous transport input ssh transport output telnet ssh The pipe symbol is also used as an OR within a regular expression, as shown in the next examples.

Normally, show ip interface brief summarizes all the interfaces found on a router. Some routers have a large number of interfaces, making even this simplified display cumbersome.

In the following text, some of the interfaces are grouped into multilinks and others are turned off. Finding the detail you need is complicated by the long and confusing output: In configuration mode, create a shortened version of a command as shown here. Redirecting output enables an administrator to collect information for archiving or to share with other troubleshooters and save it as a text file. Redirect just creates the file, whereas tee also displays the content in session.

Any filesystem supported by that router is supported, so output can be pointed at flash, tftp, ftp, http, and other destinations. The syntax to use this function is Show command redirect file Show command tee file The next examples show the running configuration being piped to TFTP. In the first example, the output is redirected.

The second example tees the output so that it builds the TFTP file and displays on screen. Foard-rtr01 show running-configuration redirect tftp: Building configuration Current configuration: Ping tests connectivity and is so commonly used that even end users are passingly familiar with it. A ping response shows that a working path between two end points exists. End systems sometimes have firewalls that prevent response, but generally ping is a reasonable first test of network connectivity: Foard-rtr01 ping First, pay attention to the pattern of the response.

Alternating success and failure!.!.!

Second, pay attention to the response time. Many applications depend on quick response. Voice, for instance, assumes a round-trip time of less than ms. The response time can also clue the troubleshooter to utilization issues. If the response time is much larger than usual that might indicate a heavy traffic load and queuing. If you notice that the minimum and maximum times vary widely, this could also be a sign of queuing because of a heavy load.

Ping can do a lot more than that simple test, however. Privileged mode supports an extended ping that enables every aspect of ping to be controlled. This opens up many more tests that can be accomplished with the humble command. The following example below an extended ping. Notice that the command ping—with no destination specified—is entered in privileged mode. The example sends five pings of bytes, then five of bytes, continuing to byte pings. The DF bit do not fragment is set.

A more detailed explanation of the command is found after the example: Foard-rtr01 ping Protocol [ip]: Target IP address: Datagram size []: Timeout in seconds [2]: Extended commands [n]: Data pattern [0xABCD]: Loose, Strict, Record, Timestamp, Verbose[none]: Sweep range of sizes [n]: Sending 75, [ Packet sent with a source address of Selecting all the defaults is similar to a normal ping.

Sometimes testing involves repeatedly pinging for instance, when you believe that an interface is flapping up and down. An extended ping with a repeat count of can be used to interactively test the network over a period of time. Pings can be set to different packet sizes through the Datagram Size variable. The router can automate testing a range of sizes. To do so, use the extended commands and choose to sweep a range of sizes.

If a router is asked to forward a packet that is larger than the MTU of the transmitting link, the router normally breaks the packet into smaller pieces.

Setting the DF bit instructs receiving routers to discard the traffic rather than fragment it. When the MTU limit is reached, all subsequent pings will be dropped. Pings are normally sourced from the transmitting interface.

Using an internal interface as the source shows that the receiving device and the intermediate routers understand how to route back to that prefix. A final idea is to try different Type of Service settings.

Many networks now carry voice, video, and prioritized data. Like ping, there is an extended version of traceroute. It has a few of the same capabilities, with one other significant testing ability. This can be used to test application performance for applications that use UDP, such as voice. This is important when trying to diagnose the affects of firewalls and access-lists. An example extended traceroute is shown next. The only choice specified in the example is to use UDP port Newton-rtr01 traceroute Protocol [ip]: Numeric display [n]: Timeout in seconds [3]: Probe count [3]: Minimum Time to Live [1]: Maximum Time to Live [30]: Port Number []: Type escape sequence to abort.

Tracing the route to Telnet does not offer many options, but by changing the target port, different network services can be tested. The following examples show that email and the web server respond on the appropriate ports: Foard-rtr01 telnet www.

Open www. Fri, 4 Sep Several commands describe the functional state of an IOS device. If network hardware is suspected, a good place to start troubleshooting is to understand the external environment. The show environment all command displays information about the temperature within the device and the state of the power supplies.

Especially when troubleshooting remotely it is easy to forget power and air conditioning, but problems in either area can lead to device malfunction: Unit is on. Temperature readings: Of course, this information is much more useful if obtained before a problem occurs and connectivity drops!

By comparing the inventory to previous inventories, it is possible to recognize differences caused, presumably, by hardware failure. If the organization has a Cisco SmartNet maintenance contract, the serial number and part-number information is necessary to obtain spares: Foard-rtr01 show inventory NAME: V03 , SN: V01 , SN: A lack of memory can also cause a network issue.

The show memory command displays the state of memory on a device; focus on the Free column to determine if enough is available. Show controller can show some information about the interface—serial interfaces in particular report things such as cable information here. Show interface shown next displays a good deal of information about the state of the interface.

In particular, pay attention to four measurements: Signify that the router had more traffic than it could process. Some amount of drops is excusable, but drops could be related to CPU oversaturation. Double-check the processor with the show processes cpu command. Usually mean that the line is congested.

These errors show duplex errors, interface problems, and CRC errors. Usually related to duplex issues. Cisco IOS devices support these tools and in many cases supply detailed information to the management system.

This section describes the methods used to coordinate with these tools. Packet Sniffing Packet capture from a laptop or specialized device enables low-level vision into the exact traffic flowing over a link.

Capturing traffic can show errors and underlying protocol traffic. The issue with packet capture is that switches do not forward all traffic out all ports, so it is difficult to find a port from which to see all traffic. SPAN is then pointed to an output port, to which a packet capture tool is attached. A second switch can then capture the VLAN and output it to a port. From there it can be copied off for inspection on a PC: Netflow Netflow collects summaries of traffic information and transmits the summary to a Netflow collector.

Netflow is enabled on each monitored interface. Netflow supports a version 5 and version 9; this should be set to match the requirements of your network management system.

Finally, Netflow exports information to a target IP address. The commands to accomplish these actions are shown here: SNMP is supported by most network monitoring systems.

The router also has a tool to react to events through embedded event manager EEM. SNMP is set up by identifying a server and listing the events to be monitored. If snmp-server enable traps is used without specifying specific events, all traps are monitored: EEM applets are starting to appear on the Internet, both at Cisco.

A simple example EEM applet is shown next. This applet logs a Syslog message and outputs a message to the console in reaction to an administrator entering configuration mode: Authorized access only.

Movement to consolidate networks has collapsed storage and virtualization, and telephony has put more traffic on Ethernet. Maintaining this critical infrastructure involves understanding the component pieces: Poor forwarding performance on switches is usually associated with cabling and port problems, duplex mismatch, or TCAM issues. Problems at the physical layer can be seen from show interface, show interface counters and show interface counters errors.

Look for the following errors: Align-Err, runts: Alignment errors are usually associated with cabling, NICs, or duplex mismatch. Frame Check Sequence errors are usually associated with a cabling issue.


The transmission buffers are full. Commonly associated with switching a faster link to a slower link. Suspect the transmitting NIC. Collisions are a sign of duplex mismatch.

An example of these commands is shown here. The switch will adjust the port to be straight through or crossover as needed. Half-duplex is unusual in modern networks, so duplex mismatch usually occur when one port is set to auto and the other to full. Spanning Tree Redundancy is a common technique to increase availability in computer networks. Ethernet redundancy would look like multiple core switches and multiple paths between workgroup switches and the core. Of course, multiple paths mean loops, and Ethernet lacks a mechanism for dealing with loops.

Spanning Tree is a protocol that detects potential loops and breaks them: Each switch starts believing it is the root. If a switch receives a BPDU with a different root, it compares roots.

If the received BPDU has a lower root, the switch changes root and recalculates cost to the root. The port that received the superior BPDU is the root port—the port that leads to the root.

Other ports are designated ports—ports leading away from the root. If a switch receives two BPDUs with the same root but different costs, it uses the lower cost port.

The port with the higher cost is blocked it filters all traffic except BPDUs to prevent a loop. Blocked ports are also called non-designated. At the end of the process there will be one root bridge. Each nonroot switch will have one root port. Spanning tree status can be seen using the show spanning-tree [vlan vland-id] command, as shown here: This command shows root status, cost, and timers: Designated root has priority , address d. Over a short time traffic would accrete in the loop until it consumed all capacity.

This is called a broadcast storm. Broadcast storms are still a real danger, but spanning tree has mitigated this almost entirely. The danger today is that—through protocol failure or administrative misprogramming—when a broadcast storm forms, few administrators have seen it before and know how to deal with it.

A broadcast storm can be diagnosed when the switches become saturated with traffic. All the traffic lights will be solid, the switch will be slow to respond, and users will complain about network speed. The only fix for a broadcast storm is to break the loop. If the switches are accessible, it might be possible to fix spanningtree.

Otherwise, the administrator must manually remove redundant links. When there are multiple links between two switches it seems intuitive that, rather than turn one off, the switches should use all the links together. This is possible using Etherchannel.

Etherchannel logically combines several physical links between switches and spanning tree treats the bundle as a single port. Up to eight physical lines may be combined in this way. Etherchannel failures cluster into three groups: If Etherchannel will not form, look for inconsistencies between ports. If only one side is configured for Etherchannel, look for Etherchannel ports that are error-disabled.

CCNP TSHOOT 642-832 Lab Guide.pdf

This is because traffic is statistically multiplexed using a three-bit hash. This means that the traffic is split over eight paths, and an etherchannel of three links will split the load in a 2: Fix this by using 2, 4, or 8 links. Second, the hash uses a userselectable Ethernet or IP field. If all traffic comes from a single source and the switch is hashing on source MAC, it will not multiplex. Fix this by selecting a different hashing method. Switches are interconnected by Ethernet lines that use This is called the Cabling issues, power outage, or bad switch ports n Switch issues: Software bugs, hardware bugs, loops, and ARP issues n Logic issues: Two commands can help identify the path taken: Shows intermediate MACs from source to destination Switches keep several mapping tables.

Each of these tables is shown in the following table, as well as the IOS command to examine the table. Troubleshooting the control plane the Layer 3 structures is identical between the two. This means that OSPF runs identically on the two platforms.

Related titles

The data plane the structures and hardware that handle frame forwarding is different between routers and Layer 3 switches. In both cases, show ip cef shows the cef forwarding table, and show adjacency shows the Layer 2 headers used in forwarding. Catalyst , , and switches can also use show platform to see detailed forwarding information. Catalyst switches display forwarding details using show mls cef commands. Another difference between routers and Layer 3 switches, in the context of troubleshooting intervlan routing, is the concept of an SVI Switched Virtual Interface.

Routers forward traffic between ports using Layer 3 information. Layer 3 switches can have multiple ports in the same vlan and pass traffic between them using MAC information.

Finally, a switch can treat a port as a separate routed port. From a troubleshooting perspective, routed ports do not run switching protocols like Spanning Tree or Etherchannel. SVIs, on the other hand, are extremely stable.

First-Hop Redundancy Hosts are configured with a default gateway—a router address that will pass traffic off the local subnet. The problem is that router failures strand the hosts. The solution is first-hop redundancy protocols, which enable two routers to cooperatively support a single IP, which can then be given to hosts as a default gateway. One router is the active and one is the standby. The routers pass keepalives that enable the standby to recognize failure of the primary router.

HSRP is configured under the interface using standby commands. By default, each HSRP speaker has a priority of The speaker with the highest priority is the active router. If a new router starts however, HSRP does not change the active router until the failure of the active router. To change this so that the higher priority is instantly recognized, use the preempt command.

An HSRP snippet is shown here to illustrate the configuration: Similarly, show standby interface and debug standby have equivalents for the other first-hop redundancy protocols. Network Layer Connectivity Routers use three tables to make routing decisions: Each entry in the routing table has an output interface or next hop. When a determination of the next hop has been made, the router needs to turn this information into a destination Layer 2 address. For this purpose, mapping tables are maintained that match Layer 2 and Layer 3 addresses.

The ARP table show ip arp and the frame-relay map show frame-relay map are examples of this. CEF combines information from the routing table and the various mapping tables to optimize routing and to optimize the construction of new Layer 2 headers. CEF entries may be viewed using show ip cef and associated commands. Regardless of the protocol, troubleshooting routing protocol issues have some basic logic that is true for any routing protocol.

Troubleshooting routing issues always starts with looking at the routing table. Use ping to test connectivity, show ip route to inspect the routing table to see if the route is present, and traceroute to inspect how traffic is forwarding.

Troubleshooting routing issues can be summarized by answering three basic questions: Is the correct route advertised? Is the correct route communicated? Is there a more desirable path lower AD or longer prefix length? EIGRP stores information in three tables that can be interrogated. Table Command Interface table: Lists discovered neighbors Show ip eigrp neighbors Topology table: Verify that the router attached to the destination subnet is advertising the route.

There are several ways to see the advertised subnets; two good ways are either direct interrogation of the running configuration using show running-config section eigrp or by reviewing the protocol settings using show ip protocol shown here: Gateway Distance Last Update Is the Correct Route Communicated?

EIGRP shares only routes with neighbors—devices with which it has exchanged hellos. Verify that connected devices are neighbors using show ip eigrp neighbors.

Network technologies and trends

EIGRP neighborship requires bidirectional communication, authentication, that the AS be the same, and that timers are close to the same. EIGRP also sends only hellos over interfaces that match a network statement. Distribution lists would be listed in show ip protocol.

Is There a More Desirable Path? So this book helps you pass not by memorization, but by helping you truly learn and understand the topics. The TSHOOT exam is just one of the foundation topics in the CCNP Routing and Switching certification, and the knowledge contained within is vitally important to consider yourself a truly skilled routing and switching engineer or specialist.

This book would do you a disservice if it did not attempt to help you learn the material. This book is not designed to be a general networking topics book, although it can be used for that purpose. Although other objectives can be achieved from using this book, the book is written with one goal in mind: to help you pass the exam.

You should have either taken the course, read through the TSHOOT course material or this book, or have a couple of years of troubleshooting experience. Cisco Certifications and Exams Cisco offers four levels of routing and switching certification, each with an increasing level of proficiency: Entry, Associate, Professional, and Expert.

There are others as well, but this book focuses on the certifications for enterprise networks. For most exams, Cisco does not publish the scores needed for passing.

You need to take the exam to find that out for yourself. There you can find out other exam details such as exam topics and how to register for an exam. The strategy you use to prepare for the TSHOOT exam might be slightly different than strategies used by other readers, mainly based on the skills, knowledge, and experience you have already obtained. For example, if you have attended the TSHOOT course, you might take a different approach than someone who learned troubleshooting through onthe-job training.

Regardless of the strategy you use or the background you have, this book is designed to help you get to the point where you can pass the exam with the least amount of time required. How This Book Is Organized Although this book can be read cover to cover, it is designed to be flexible and enable you to easily move between chapters to cover only the material that you need more work with.

The chapters can be covered in any order, although some chapters are related and build upon each other. If you do intend to read them all, the order in the book is an excellent sequence to use. Also discussed in this chapter is a collection of commonly used maintenance approaches.

Next, this chapter lists common maintenance tasks, emphasizes the importance of regularly scheduled maintenance, and summarizes critical areas of network performance. Finally, this chapter identifies how to compile a set of network maintenance tools that complement your network maintenance plan. Also discussed is each subprocess in a structured troubleshooting approach.

Finally, this chapter shows how maintenance processes and troubleshooting process can work in tandem to complement one another.

Also, this chapter introduces spanning tree protocol STP , which allows a Layer 2 topology to have redundant links while avoiding the side effects of a looped Layer 2 topology, such as a broadcast storm. You then learn strategies for troubleshooting an STP issue. Finally, troubleshooting an EtherChannel connection is addressed. This chapter concludes with a trouble ticket and an associated topology. You are also given show command output baseline output and output collected after the reported issue occurred.

Based on the information provided, you hypothesize an underlying cause for the reported issue and develop a solution. You can then compare your solution with a suggested solution. Troubleshooting procedures are also compared for these platforms. Two approaches for routing packets using Layer 3 switches are also discussed.

These approaches are using routed ports and using switched virtual interfaces SVIs. Next, this chapter discusses three approaches to providing first-hop router redundancy. Examined next is the architecture of a Cisco Catalyst switch and the different architectural components that could become troubleshooting targets. Finally, this chapter presents you with a trouble ticket and an associated topology. You are also given show and debug command output baseline output and output collected after a reported issue occurred.

You see how Layer 2 information can be learned and stored in a router. Additionally, you are presented with a collection of show commands, useful for troubleshooting IP routing. Again, you are presented with a collection of show and debug commands useful for troubleshooting various EIGRP operations.

TSHOOT_Exam_Guide_v3.2 - The Online CCNP TSHOOT 642-832...

Finally, this chapter challenges you with a trouble ticket and an associated topology. You are also given show command output. You are then presented with a collection of show and debug commands useful for troubleshooting OSPF operations. This chapter next presents you with a trouble ticket and an associated topology. Based on the information provided, you hypothesize an underlying cause for the reported issues and develop solutions.

You can then compare your solutions with the suggested solutions. This chapter also introduces the concept of route redistribution and discusses how a route from one routing process can be injected into a different routing process. Common route redistribution troubleshooting targets are identified, along with strategies for troubleshooting route redistribution. Finally, this chapter challenges you with another trouble ticket and an associated topology. You are then presented with a collection of show and debug commands useful for troubleshooting BGP operations.

You are given show command output. Finally, this chapter discusses how to troubleshoot performance issues on a router, focusing on CPU utilization, packet-switching modes, and memory utilization. These planes are the management plane, the control plane, and the data plane. Once you review these security measures, this chapter considers how your troubleshooting efforts might be impacted by having various layers of security in place.

Although complete configuration details for Cisco IOS firewalls and AAA is beyond the scope of the TSHOOT curriculum, as a reference, this chapter does provide a couple of basic configuration examples with an explanation of the syntax used. You are also given show command output and a syntax reference. Based on the information provided, you hypothesize how to correct the reported issues. As a reference, sample topologies are provided, along with their configurations. Common NAT troubleshooting targets are identified, and a syntax reference is provided to aid in troubleshooting NAT issues.

This section also presents a collection of commands that could prove to be useful in troubleshooting a suspected DHCP issue. You are also given show and debug command output, which confirms the reported issue. Then, you are challenged to hypothesize how to correct the reported issue.

CCNP TSHOOT 642 832 Quick Reference

Several protocols are involved when a Cisco IP Phone registers with its call agent in order to place and receive voice calls. You review the function of these protocols along with recommendations for troubleshooting voice issues.An access-list is used to block all nonapproved traffic.

The feedback was overwhelmingly positive from the online community! Spanning tree status can be seen using the show spanning-tree [vlan vland-id] command, as shown here: Broadcast storms are still a real danger, but spanning tree has mitigated this almost entirely. You are then presented with a collection of show and debug commands useful for troubleshooting OSPF operations.

Any device that is well maintained will be more reliable, suffers fewer problems, and will be easier and quicker to repair.

The alias command can make this easier. This is because traffic is statistically multiplexed using a three-bit hash. The example sends five pings of bytes, then five of bytes, continuing to byte pings.

Netflow Netflow collects summaries of traffic information and transmits the summary to a Netflow collector.