Un nuevo paradigma para la resolución de problemas de redes | NETSCOUT
Documentos técnicos
| Documentos técnicos |

A NEW PARADIGM FOR
NETWORK PROBLEM SOLVING

48 por ciento de las organizaciones tardan más de medio día en cerrar las notificaciones de incidencias.
Es una paradoja. A medida que se incorpora más fiabilidad a las redes, las organizaciones siguen pasando mucho tiempo resolviendo problemas y son presionados para reducir el tiempo de resolución de problemas. This white paper discusses state-of-the-art network problem solving and how a new approach – based on the NETSCOUT OneTouch™ AT Network Assistant – can reduce troubleshooting time by one full week each month.

Are Problems a Thing of the Past?

Cada año, las redes se vuelven más fiables. Los nuevos estándares prometen interoperabilidad, los nuevos dispositivos simplifican la configuración y las soluciones de monitorización avanzadas ofrecen detectar los problemas, antes que se afecten los usuarios. Los departamentos de TI están entrando a una era en la que los problemas serán algo del pasado.

¿Lo hacen? A recent research study of over 300 network professionals in large - and medium - sized organizations found that:
  • 48 por ciento de las organizaciones tardan más de medio día en cerrar las notificaciones de incidencias.
  • 46 por ciento de las organizaciones reciben presiones para reducir el tiempo que se tarda en cerrar las notificaciones de incidencias.
  • Network professionals spend about 25 percent of their time solving problems
¿Por qué ocurre esto a pesar de tantos avances informáticos disponibles para eliminar problemas? Una explicación es que cada avance de la confiabilidad y simplicidad supone un avance de la tecnología que dificulta la situación: unified communications, 802.11ac, cloud computing or IPv6. Con independencia de las razones, queda mucho por hacer en materia de mejora de la productividad de la resolución de problemas.

To increase productivity, troubleshooting tools not only need to keep up with technology changes, but must continue to improve processes used to solve problems.

How Troubleshooting is Done Today

The vast majority (72 percent) of organizations do not follow a standardized troubleshooting process. Not only does this process vary within an organization but the tools used to troubleshoot problems vary substantially. Survey respondents reported using eight different types of tools to solve problems. En el 47% de los casos, utilizaron dos o más herramientas. Dada la variación en las herramientas y prácticas de solución de problemas, no sorprende que el 63% de las sesiones de solución de problemas durase más de una hora.

There is a part of problem solving that is worth considering separately. En muchos casos, los técnicos no pueden resolver el problema por sí mismos. Sometimes they need additional help with especially difficult problems. In other instances, it’s because the problem lies outside their domain of responsibility, and they need to work with a separate group inside (server management or application developers) or outside (service providers or equipment vendors) the enterprise. Esta situación es común: nuestras investigaciones indican que el 41% de los problemas requieren colaboraciones de este tipo. This can take too long for at least two reasons. En primer lugar, no siempre es fácil mostrar a las partes responsables el problema en el momento en que se produce. Second, the technician may not have the ability to easily capture the trace files that are often required (19 percent of the time) for these problems.
To increase productivity, troubleshooting tools not only need to keep up with technology changes, but must continue to improve processes used to solve problems

Estudio de técnicas de solución de problemas

This white paper refers to a NETSCOUT research study of 315 network professionals in April 2012. The respondents came primarily from medium- to large-sized networks in a variety of industries. Most of them were top-level networking support staff.

Figura 1: ¿Cuáles de las siguientes herramientas utilizó para resolver los problemas más recientes de un usuario?

Figura 2: ¿Cuántas notificaciones de incidencia suele procesar en un mes?

Figura 3: What is your group’s average time to close a trouble ticket? El 48% contestó que más de cuatro horas.

Figura 4: ¿Cuál fue el origen del último problema de un usuario que resolvió? (Se permitían varias respuestas.)

The survey asked respondents to identify the root cause of their most recent user-reported problem (respondents could select more than one root cause). The most common cause was network problems (wired or Wi-Fi), occurring in 27 percent of instances. However, end-user configuration or operation problems combined were at fault in 42 percent of cases.

The OneTouch AT identifies the most common network problems in about one minute1

Changing the Problem-solving Paradigm

At NETSCOUT, we looked to shorten the entire problem-solving process. The process, as described earlier, traditionally consists of two steps – solo troubleshooting and collaboration when necessary. To streamline troubleshooting, NETSCOUT developed a three-step process and designed a new tool based on it. The three steps are:

1. Pruebas automatizadas
2. Solución de problemas
3. Colaboración

The OneTouch™ AT Network Assistant, enhances each of the steps and greatly reduces the time to solve problems.

Paso 1: Pruebas automatizadas

It may seem counterintuitive that adding a step reduces time. But if the additional step actually saves more time in subsequent steps, the total time is reduced. That’s the idea behind automated testing.

The OneTouch AT identifies the most common network problems in about one minute1. It performs a thorough network analysis from the end-user’s point-of-view. Such an analysis, performed manually, would take roughly one hour2. The OneTouch AT performs that same testing in about a minute (tests are configurable and can take anywhere from ten seconds to a few minutes, with most being less than a minute). Results are then compared against user-defined limits to provide a simple pass/fail result. This approach allows technicians to find the most common problems that result in end-user complaints.

Las comprobaciones automatizadas presentan numerosas ventajas. En primer lugar, son mucho más rápidas que una comprobación típica de ensayo y error. En segundo lugar, son más detalladas que un enfoque manual, que significa que puede encontrar problemas que un técnico no consideraría. En tercer lugar, permiten a cualquiera (con independencia del nivel de competencia) realizar las comprobaciones e identificar los problemas.

Paso 2: Solución de problemas

While the AutoTest uncovers a wide variety of problems on its own, not all problems can be found that way. The OneTouch AT provides a veritable arsenal of troubleshooting power to reduce the time spent in this phase.

AutoTest – even if the initial AutoTest does not identify the problem, all the measurement results are ready and available to help the technician understand what is happening. Further, the AutoTest can be modified in seconds and re-run to test a different server, application or wireless connection.

Wired Tests – a complete set of tests provide information on the cable, Power over Ethernet, the nearest switch and network services. The OneTouch AT features a web browser, Telnet and a SSH client to assist with configuration of network devices including switches and access points. It features a toner and can flash switch port lights to help locate unmarked cables in congested closets. A video probe can be connected to the OneTouch AT to inspect the endface of fiber optic connectors for contamination.

The OneTouch AT can pay for itself within 4 months with time savings while troubleshooting and validating networks
Wireless Tests – OneTouch AT provides more analysis of the Wi-Fi network than a library of wireless freeware and shareware tools, and provides answers in an easy to understand format. The OneTouch AT discovers all the networks, AP’s and clients in range and quickly identifies problems such as improper security, interference, bandwidth hogs, overloaded channels, unauthorized devices and more.

Paso 3: Colaboración

Tal como se ha indicado anteriormente, los técnicos de redes deben trabajar de forma regular con otra persona para resolver los problemas. The process of getting the right information to the right people, however, can drag on for days. Even if the technician is able to work on other problems during this period, that’s little comfort to an end user who can’t get their job done or the IT manager missing targets for trouble ticket times.

The OneTouch AT includes features specifically designed to expedite collaborative troubleshooting with the Link-Live Cloud Service. With Link-Live Cloud Service, everything is always captured with zero-touch reporting, providing you with complete records of your work and results, at all times. Esta base de datos completa y consultable le permite identificar fácilmente los cambios en la red. No existe ningún límite de espacio, límite de tiempo y necesidad de recuperar y transferir datos desde dispositivos de comprobación a almacenamiento al final del día. This cloud service is available to all Handheld Network Tools: LinkSprinter, LinkRunner AT, and the AirCheck G2, all automatically upload their test results at the moment they happen. If you don’t have connectivity at that drop, the testers can buffer results, which are pushed to the Link-Live Cloud Service when connectivity returns. Los técnicos ya no tienen que ser los guardianes y transportadores de los datos de prueba, o incluso recordar presionar guardar. En vez, pueden duplicar su productividad y terminar trabajos que solían tomar semanas en unos cuantos días. In addition, managers can have access to the test results dashboards.

Reporting – a detailed report of everything that the OneTouch AT tested and observed will be recorded in the Link-Live Cloud Service. This allows the tech to show a colleague exactly what is happening when they are observing the problem. These results include results a less-experienced technician might not have looked at but are there for more knowledgeable team members to evaluate.

In-line Packet Capture – a trace file is indispensable for very difficult problems or as evidence to an outside group such as application developers, service providers or equipment suppliers. Para recopilar esta información suele ser necesario volver a configurar el switch o un punto de conexión de red. Este proceso puede tardar 30 minutos o más. Worse, many techs may not have access to switch provisioning or a tap. Esto supone un mayor retraso, dado que el problema se transfiere a otra persona.

El OneTouch AT puede realizar una captura de paquete en línea en solo unos cuantos toques de pantalla sin necesidad de acceder al switch o punto de conexión. This means the tech can capture the problem packets immediately while the user demonstrates the problem.

Web Remote Interface – while it’s not always possible to get a colleague physically in the location of the problem, the OneTouch AT can be accessed and controlled through a remote device such as a PC, tablet or smartphone. Not only can the remote user see what the tech is seeing, but they can control the OneTouch AT and export trace files or reports to their device.

Camera – connect a webcam to the OneTouch AT USB port and the remote helper can see livevideo of the physical environment the tech is working in. This is useful if the tech is in a wiringcloset or a data center and the remote colleague needs to see the switch or patch panel, for example.

Savings

The first step in estimating savings from the OneTouch AT is to look at the time saved in each of the three parts of the test.

Automated Testing – Table 1 compares the amount of time it would take to perform the AutoTest functions with the actual time of the AutoTest. El tiempo depende de la habilidad del técnico así como de cuántas aplicaciones se necesitaría comprobar.

Troubleshooting – it’s less straightforward to quantify these savings, as it is highly dependent on the actual problem and the skill of the technician. Users of other NETSCOUT Handheld Network Test Solutions generally report 30 percent to 40 percent faster troubleshooting, but we will set that aside and consider it a “bonus” savings in addition to what is demonstrated here.

Collaboration – to quantify the time savings in these scenarios, we compared time to set up a packet capture using port mirroring (roughly 20 minutes) versus the inline packet capture with the OneTouch AT (three minutes). En casos donde el técnico no tenga acceso a la reconfiguración del switch, el ahorro de tiempo sería mucho mayor.

Una mejor colaboración ofrece un mayor beneficio al reducir el tiempo en general para cerrar las notificaciones de incidencias. Sin el OneTouch AT, es frecuentemente difícil obtener todos los datos relevantes frente a las personas adecuadas rápidamente. Esta es una causa significativa de notificaciones de incidencias que se alargan, a veces durante días. Armed with the OneTouch AT, the first responder easily generates a report or a trace file and shares these plus provides remote access for the rest of the team in real time. So while the total amount of time the staff spends on a problem may not be reduced, the time the end user spends waiting for a resolution is greatly reduced.

Again, such a benefit is hard to quantify – so we won’t – but for many organizations this may be more valuable than actual hours saved for the department staff.

Conclusiones

An estimation of the savings expected from using the OneTouch AT is presented in Table 1. Even ignoring the time saved in solo troubleshooting and purchase of the top of the line model, one would expect payback in less than six months.

Ahorros de AutoTest
Notificaciones de incidencias por mes por técnico 20 (promedio)
Minutos por notificación 90
Tiempo de Autotest 1 minuto
Tiempo para realizar manualmente funciones de AutoTest
(from Table 1)
60 minutos
Tiempo ahorrado por notificación 59 minutos
Horas ahorradas por mes 19,7 por técnico
Ahorros por colaboración
Porcentaje que requiere captura de paquete 19% (Promedio)
Número que requiere captura de paquete 3,8
Tiempo para la configuración de captura de paquete 20 minutos
Configuración de captura de paquete con OneTouch AT 3 minutos
Tiempo ahorrado por captura 17 minutos
Horas ahorradas por mes 1,1 por técnico
Número de usuarios 2 por OneTouch AT
Tiempo total ahorrado 41 horas por mes
Ahorros en dólares
Tasa por hora 60 dólares
Total de ahorro mensual 2.489 dólares
Coste de OneTouch AT 10.000 dólares
Recuperación 4,0 meses

Tabla 1: An estimation of time and cost savings provided by OneTouch AT.

Figura 5: Summarizes the concepts of this paper: the ways in which the OneTouch AT saves time throughout the entire problem-solving process as compared to traditional methods.

Apéndice A: una hora de resolución de problemas en un minuto

Atacar la raíz del problema es crítico pero puede involucrar pasos adicionales. Por ejemplo, cuando uno va al médico, sin importar la dolencia que se tenga, primero lo atiende una enfermera que inmediatamente lo pesa, toma su temperatura, su presión arterial y revisa su historia clínica. Este paso no solo le ahorra el médico tiempo, sino con frecuencia captura problemas que podrían no percibirse.

Este concepto también se aplica a la comprobación de una red. Since your team doesn’t usually include a nurse, the OneTouch AT automates a complete test of “network vital signs” into an AutoTest that compresses an hour of traditional testing into about a minute. The results are then compared against userdefined limits to provide a simple pass/fail result. Este enfoque no solamente ahorra tiempo, sino que permite a los técnicos resolver más problemas.

Paso de comprobación Red OneTouch
Asistente (AutoTest)
Métodos tradicionales
Conectividad básica (por cable o Wi-Fi) 1 minuto Comprobador de cable, PC, herramientas de Wi-Fi 5 minutos
Servicios de infraestructura PC, herramientas 5 minutos
Operación y rendimiento inalámbrico Dos PC, iPerf 10 minutos
Los servicios de red y rendimiento de aplicación Captura de paquete, analizador de protocolo 40 minutos
(tres aplicaciones)

Tabla 2: El AutoTest de OneTouch realiza casi una hora de comprobación manual en un minuto.

Basic Connectivity – OneTouch AT tests both wired and Wi-Fi connectivity. On the wired side, it checks the physical layer (including cabling and Power over Ethernet), identifies the switch port, speed and duplex settings and identifies the switch port and VLAN. For Wi-Fi, it verifies connectivity and security settings for the nearest AP and tests connection speeds.

Infrastructure Services – OneTouch AT tests availability and response time of DNS and DHCP across both the wired and wireless network.

Wireless Operation and Performance – the exclusive test measures the actual wireless performance by sending a stream of traffic out the wireless port, through the nearest AP, the wired infrastructure and back to its wired port. The test runs simultaneously in the reverse direction with programmable upstream and downstream rates. The test provides measurement results for throughput, loss, latency and jitter in both directions. These latter two measurements are vital for quality performance of real time application such as streaming video or voice over Wi-Fi.

Network Services and Application Performance – these tests provide a detailed breakdown of application performance by analyzing an actual interaction with the server/service under test. Seven different tests/applications are supported and can be customized for specific sites or applications whether hosted locally or through cloud-based providers.

The detailed breakdown provides the results shown in Figure 7 and shows the results for both the wired and Wi-Fi network side-by-side for easy comparison.

While the overall measurement can be used to quantify the performance of the application, the detail can be used to determine the cause of the slow performance, whether it’s the network, application server, or the DNS server. While an expert can provide this level of analysis in ten or twenty minutes with a protocol analyzer (once they have a trace file), the OneTouch AT provides it under a minute as part of a standard AutoTest.

Figura 6: The test measures performance of the wired and Wi-Fi network.

Figura 7: The application performance tests provide a detailed breakdown of the response time of servers and services.

Appendix B: List of problems that can be discovered by the OneTouch AT Network Assistant AutoTest

Fiber problems Wrong SFP/vendor mismatch, Dirty fiber endface*, Dead port/broken fiber, Low power
Twisted pair problems Open cable, Bad cable mapping, Shorted cables, Mislabeled/undocumented cables*, Too long cable, Dead port
PoE Not present or disabled, Switch unable to supply adequate power, Wrong pins, Low voltage, Non-Ethernet voltage, Low power under load, Class 4 negotiation mismatch
Enlace Polarity mismatch, Low link level, Receive pair issues (MDIX), Speed mismatch, Duplex mismatch
Switch port Incorrect switch, Incorrect port, Incorrect data VLAN*, Incorrect voice VLAN*, Unstable switch uptime*, Switch congestion*, Switch errors*, FCS errors*, Frame size errors*, Other frame errors (7)*, Excessive broadcast traffic*, Excessive multicast traffic
Wi-Fi Security settings wrong, AP missing, AP misconfigured, AP not connected, WLAN controller problems*, Excessive noise*, AP congestion*, Channel over utilized*, Too many APs on channel*, AP overlap on channels*, Roaming problems*, Unauthorized APs*, Finding rogue APs*, Ad hoc networks*, Insufficient network coverage, Slow connection, Bandwidth hogs APs and client*, Bad client NIC*
Veri-Fi QoS settings wrong*, MTU problems*, Port problems*, Upstream bandwidth issues, Downstream bandwidth issues, IPv6 issues*, Excessive loss, Latency issues*, Jitter issues*, Sequencing issues*
DHCP Missing, Slow, Out of addresses, Incorrect lease time, Rogue DHCP server, Wired versus Wi-Fi configuration problems, Duplicate static IP address, IP address hijacked, Incorrect address delivery, Incorrect subnet delivery, Incorrect router address, Incorrect DNS address
DNS Missing, Slow, No secondary server*, Wired versus Wi-Fi configuration problems*
Router Missing / Failed, Not IPv6 capable*, Unstable gateway uptime*, Overloaded*, Bad traffic*, Incorrect routing protocols*
Discovery Wrong VLAN*, Wrong subnet*, Unexpected IPv4/IPv6 devices
Web (HTTP) DNS lookup failure, DNS lookup slow, Server unavailable, Slow connectivity, Server slow to start, Server slow to complete, Wired versus Wi-Fi transport problems, IPv4 versus IPv6 transport problems
Ping (ICMP) DNS lookup failure, DNS lookup slow, Server unavailable, Slow connectivity, MTU misconfigurations, Wired versus Wi-Fi transport problems, IPv4 versus IPv6 transport problems

Appendix B: (continued)

Conectar (TCP) DNS lookup failure, DNS lookup slow, Server unavailable, Slow connectivity, Firewall misconfigured for ports, Wired versus Wi-Fi transport problems, IPv4 versus IPv6 transport problems
Multicast (IGMP) Server not multicasting, Switch IGMP snooping disabled, Incorrect port configuration, Server authentication
Archivo (FTP) Slow WAN, DNS lookup failure, DNS lookup slow, Server unavailable, Slow connectivity, Server slow to start, Server slow to complete, Wired versus Wi-Fi transport problems, IPv4 versus IPv6 transport problems
Vídeo (RTSP) Slow WAN, DNS lookup failure, DNS lookup slow, Server unavailable, Slow connectivity, Server slow to start, Server slow to complete, Wired versus Wi-Fi transport problems, IPv4 versus IPv6 transport problems

* May require a secondary test after the AutoTest.

1 See appendix A, “An Hour of Troubleshooting in One Minute”
2 See appendix B, “Problems That can be Discovered by the OneTouch AT Network Assistant AutoTest”

 
 
Powered By OneLink