2 troubleshooting network problems using log a

... routing updates a From the enable privileged EXEC mode, examine the routing table entries using command debug ip rip command on each router b What are the three operations that take place listed ... include any other type of interface even though a specific router may contain one An example of this might be an ISDN BRI interface The string in parenthesis is the legal abbreviation that can be ... proper IP address, subnet mask, and default gateway Step Verify that the internetwork is functioning by pinging the FastEthernet interface of the other router a From the host attached to the GAD, ping...

Ngày tải lên: 21/12/2013, 19:15

... considering network traffic, we break it into three main classes: broadcast, multicast, and unicast Each classification has a distinct characteristic that determines how packets in that class are handled ... pinpoint a problem Network Maps In our brief discussion about network placement, we have already looked at several different network maps A network map, or network diagram, is a diagram showing all ... operate at this layer The Data Link Layer The data link layer provides a means of transporting data across a physical network Its primary purpose is to provide an addressing scheme that can be...

Ngày tải lên: 16/03/2014, 12:20

... criteria, you can mark those of particular interest Marked packets stand out with a black background and white text, as shown in Figure 4-2 (You can also sort out only marked packets when saving packet ... powerful features of the Save File As dialog is the ability to save a specific packet range You can choose to save only packets in a specific number range, marked packets, or packets visible as the ... File As dialog, you can specify that it print a specific packet range, marked packets only, or packets displayed as the result of a filter You can also select which of Wireshark’s three main panes...

Ngày tải lên: 14/08/2014, 14:20

... broadcast packet, our capture filter doesn’t allow it to be shown The second packet is an ARP packet that we call a gratuitous ARP A gratuitous ARP is an ARP broadcast-type packet that is used ... (TTL) value is a numerical value that determines how many times a packet can hop from one router to another across a network A value of one means that traceroute will send a packet to the destination ... scenario we learned that the reason Mandy’s computer was doing strange things was related to a spyware application that was being downloaded to her computer via a background RPC service But what...

Ngày tải lên: 14/08/2014, 14:20

... net-centric applications at once These applications, along with standard Internet and email clients, create an above-average load of traffic, but one that our network should be able to handle easily Tapping ... A Simple Port Scan portscan.pcap Attackers can use port scans to learn very critical information about a network Using specialized port-scanning software, a hacker can attempt to connect to a ... are already past the TCP handshake phase, meaning they are actively transferring data to and from our client You can get a sense of how many of these connections are taking place by looking at...

Ngày tải lên: 14/08/2014, 14:20

... a bit alarming, as shown in Figure 9-14 Figure 9-14: This is definitely not a normal ping packet This ping packet is far from standard As a matter of fact, it is carrying a secret payload that ... header, which contains additional information about the packet, such as data rate, frequency, signal level, and noise level Choose 802.11 + Radio in order to see all available packet information ... into a username and password authentication process, and as you can see in packet (Figure 9-5), this authentication attempt fails Figure 9-5: Packet shows the first authentication attempt failure...

Ngày tải lên: 14/08/2014, 14:20

... www.nostarch.com/packet.htm A N A LY Z E T H E M U S I N G Practical Packet Analysis shows how to use Wireshark to capture and then analyze packets as you take an indepth look at real-world packet analysis and network ... increase throughput performance The Beacon Frame The beacon frame is one of the most informative packets in a wireless transmission A beacon frame is sent as a broadcast packet from a WAP across a ... book that I have put into it Packet analysis is both a science and an art, similar to medicine—the network is the patient and you are the physician Just as a doctor knows the human anatomy and the...

Ngày tải lên: 14/08/2014, 14:20

... for a password, enter class If “class” does not work, ask the instructor for assistance Router>enable At the privileged EXEC mode, enter the command erase startup-config Router#erase startup-config ... type of router as well as how many interfaces the router has There is no way to effectively list all of the combinations of configurations for each router class What is provided are the identifiers ... ISDN BRI interface The string in parenthesis is the legal abbreviation that can be used in IOS command to represent the interface 4-4 CCNA 2: Routers and Routing Basics v 3.0 - Lab 4.1.4 Copyright...

Ngày tải lên: 04/11/2013, 16:15

... that is displayed regarding the global catalog requires some explanation - Evaluating Global Catalog server 'GlobalCatalogueServer' WARNING: NSPI port is not set in registry for Global Catalog ... De.mo:593;GlobalCatalogueServer:102465535;GlobalCatalogueServer.De.mo:1024-65535 Note GlobalCatalogueServer is also a Windows 2003 global catalog This warning is removed by configuring the global catalog ... - Evaluating Global Catalog server E2k3-LegacyOS - Found AD Global Catalog servers - Skipped AD Global Catalog servers without Windows Server 2003 (or unavailable Windows version) - Updating...

Ngày tải lên: 11/12/2013, 14:15

... application or service: Start the Task Manager application by pressing ++ Click the Applications tab The Applications tab provides status information and displays each application ... resolving problems that occur during system shutdown: Using Task Manager to close an unresponsive application or service Comparing normal and safe mode Bootlog.txt log entries To end an unresponsive application ... Windows XP, and Windows Server 2003 have a set of so-called default processes, which are listed in Table 12.3 You cannot use Task Manager to close any of the processes that are marked with an asterisk...

Ngày tải lên: 14/12/2013, 10:15

... the basic hardware checks Verify that all cables are attached correctly and all internal adapters are installed properly Make sure that all peripheral devices (such as keyboards) necessary to ... maintenance and take preventive measures against disaster However, problems still can arise As with any other operating system, they might be caused both by hardware malfunctions and by software ... Please insert another disk Windows NT-based OS This and similar error messages specifying different file names cannot start and displays indicate that the boot failure was caused by a damaged registry...

Ngày tải lên: 14/12/2013, 10:15

... global parameters a Configure the router using the default settings for any questions the router asks if it has already been configured The router may be named at this time if it has not been already ... been already Make sure that cisco is entered as the enable secret password Step Configure interface parameters a Configure the router using the default settings for any questions the router asks ... has already been configured If not, select any desired IP addresses to configure the interfaces Step Configuration command script a The router displays the configuration command script that was...

Ngày tải lên: 21/12/2013, 19:15

... important that a technician try to save as much time as possible Ping is a great utility to begin troubleshooting a problem Ping will help a technician determine whether the network problem is related ... Internet Instead, the loopback is an address that pings the NIC installed in the workstation you are currently using Type the command ping 127.0.0.1 Did you receive a reply back? Are the values for ... time, and TTL the same as last time? If not, what has changed? Step If the technician can successfully ping the PC address, and the loopback, then the NIC and...

Ngày tải lên: 21/12/2013, 19:15