Transcript Network Naming

Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Network Naming
Chapter 10
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Objectives
• Analyze and configure early name resolution
solutions
• Describe the function and capabilities of DNS
• Use common TCP/IP utilities to diagnose
problems with DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Overview
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
An Introduction to Name Resolution
• Computers use IP addresses to communicate
• People remember names better than numbers
• The name resolution process was created to
convert names to IP addresses (and vice versa)
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.1 Turning names into numbers
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
An Introduction to Name Resolution
(cont’d.)
• Name resolution has evolved over the years
• The Domain Name System (DNS) is the main
protocol
• New operating systems support old and new
protocols
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Test Specific
Before DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
NetBIOS/NetBEUI
• Light and efficient networking protocol
developed by Microsoft in the 1980s
– A booted computer broadcast its name along with
its MAC address
• Suitable only for small networks
– Did not provide logical addressing; no routing
– All of the broadcasting made it unacceptable for
large networks
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.2 NetBIOS broadcast
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
NetBIOS over TCP/IP (NetBT) and
Server Message Block (SMB)
• NetBT was a new TCP/IP protocol developed
by Microsoft in the 1990s
– Enabled keeping the NetBIOS names
– No longer used the Net BEUI protocol
• SMB ran on top of (and independent of)
NetBT to support sharing folders and files
– Runs by itself using TCP port 445
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
hosts
• Text file used in early TCP/IP name resolution
– Copied to all computers on the Internet
– Contained a list of IP addresses for every
computer, matched to system names
– Preceded rules for composing Internet names
– Examples:
• 192.168.2.1 fred
• 201.32.16.4 school2
• 123.21.44.16 server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
hosts (cont’d.)
• Every hosts file was updated on every system
at 2 a.m. daily
• Impractical after the Internet grew to 5000
systems
– Motivation for a more scalable name resolution
process, but hosts file still exists
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Editing the HOSTS File
• Every operating system always looks first in
the hosts file to attempt to resolve a name
– Example: Try This! sidebar
• The hosts file resolves names for every TCP/IP
application on a system
• After completing the Try This! example:
– Type ping timmy at a command prompt
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Use of hosts File Today
• Many people place shortcut names in a HOSTS
file to avoid typing long names in some TCP/IP
applications
• The Internet has replaced the hosts files with
DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
How DNS Works
• No single computer can handle all Internet
name resolution
• Delegation used
– Top-dog DNS system delegates parts of the job
– Subsidiary DNS systems delegate parts of their
work
– All DNS servers run a special DNS server program
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
How DNS Works (cont’d.)
• Top-level domain servers handle top-level
domain (TLD) names
– Some examples: com, org, net, edu, gov, mil, int
– Delegate to second-level DNS servers
• Support individual computers
• The DNS server for a domain stores the actual IP
address
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Spaces
• A hosts file uses a flat name space
– Single undivided list
• DNS uses a hierarchical name space
– A tree structure of all possible names that could
be used within a single system
– Offers administrators flexibility to assign longer,
more descriptive names
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.3 Our People name space
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Spaces (cont’d.)
• Example of a name space
– Hierarchical name space used by hard drive
volumes
• Windows NTFS or Linux’s ext3
• Can have duplicate file names stored in different parts
of the file tree
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.4 Two data.txt files in different directories
on the same system
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Name Spaces (cont’d.)
•
•
•
•
Works similarly to computer’s file system
A hierarchy of DNS domains
Organized into a tree-like structure
Root
– Located at the top of the DNS tree
– Holding area to which all domains connect
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Name Spaces (cont’d.)
• Characters are limited to uppercase and
lowercase letters, numbers 0-9, and hyphen
• Each domain can have subdomains
– Separated from the domain with a period
• The DNS server can be configured as the root
server for an intranet
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Name Spaces (cont’d.)
• Path to a file on a PC
– The root directory is on the left
– Folders and subfolders follow
– The name of file is on the right
– DNS naming convention is exactly the opposite
• Fully qualified domain name (FQDN)
– The root is on the far right
– The host name is on the far left
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.5 Private DNS network
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.6 Two DNS domains
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.7 Subdomains added
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Servers
• Three key players involved with DNS
– DNS server: a computer running DNS software
– Zone: a container for a single DNS domain that
gets populated with records
– Record: a line in the zone data that maps an FQDN
to an IP address
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Servers (cont’d.)
• The authoritative DNS server for a domain
– Lists all host names/corresponding IP addresses
• Single DNS server can act as the authoritative
name server for one or many domains
• If many DNS servers support the same
domain, the authoritative name server
distributes updates to the other name servers
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.8 A single authoritative name server can support
one or more domains.
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.9 DNS flexibility
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.10 New information passed out
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.11 Root server in action
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Servers (cont’d.)
• Benefit of hierarchical structure of DNS
– Allows multiple Web servers to have names
starting with www.
• DNS naming appends domain names to server names
• No two machines should ever have the same FQDN
• ICANN registers domain names for Internet
use
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.12 DNS domain
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Resolution
• In the early Internet years, DNS worked
interchangeably with IP addressing
• Modern Web sites need DNS to function
• IP addresses are required for connections
• Three methods for resolving the name
– Broadcasting
– Consulting the local hosts text file
– Contacting a DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Resolution: Broadcast and
hosts File
• Broadcast
– The host sends a message to all the machines on
the network
– Limited to small networks
• A hosts file functions like a little black book
109.54.94.197
138.125.163.17
127.0.0.1
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stephen.totalsem.com
roger.totalsem.com
localhost
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Name Resolution: DNS
• A PC must have DNS information entered
– In Windows Vista/7/8/10, entries are made using
the Internet Protocol Version 4 (TCP/IPv4)
Properties dialog box
– Linux allows direct editing of the /etc/resolv.conf
file with a text editor
– All operating systems provide a means of entering
DNS server information
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.13 Accessing a Web site via IP address
rather than name
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.14 Routers don’t forward broadcasts!
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.16 DNS information in Windows
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.17 Entering DNS information in Ubuntu
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.18 the ipconfig /all command
showing DNS information in Windows
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Name Resolution: An Example
• The DNS server receives the request for the IP
address of www.microsoft.com
– The DNS server checks a cache of previously
resolved FQDNs
– The DNS server contacts the DNS root servers
– The DNS root server contacts the DNS server in
charge of .com addresses
– The root server sends the IP address of
Microsoft.com DNS server to your DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.15 A host contacts its local DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.19 Checking the DNS cache
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.20 Talking to a root server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.21 Talking to the .com server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.22 Talking to microsoft.com DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Resolved FQDNs
• Your computer keeps a cache of recently
resolved FQDNs
• At Windows command prompt, type
ipconfig /displaydns to see the list
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Servers
• Many operating systems have built-in DNS
server software
– Example: Windows Server 2012 R2
– Most versions of UNIX/Linux
• Third-party DNS servers are available
• Access Windows DNS server by selecting
Start | Administrative tools | DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.23 DNS server main screen
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNA Servers (cont’d.)
• List of cached lookups
– Stores previously resolved IP addresses
• Cache-only DNS servers
– Talk only to other DNS servers
– Never the authoritative server for a domain
• Forward lookup zones
– Special storage areas
– Most important part of any DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.24 Inspecting the DNS cache
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.24 Authoritative vs. cache-only DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.26 Forward lookup zone totalhome
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
DNS Record Types – An Example
• Start of Authority (SOA) record
– Defines the single server in charge of the forward
lookup zone; SOA record is in the folder totalhome
• NS records
– Identify two DNS servers for totalhome domain
• A records
– Provide IPv4 addresses/names of all systems in
totalhome domain
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.27 Less common DNS record types
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Less Common DNS Record Types
• Canonical name (CNAME)
– An alias used to reference a computer
• MX records
– Used exclusively by SMTP servers to determine
where to send mail
• AAAA records
– Used for IPv6 (more information in Chapter 13)
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Common Types of Forward
Lookup Zones
• Primary zone: created on the DNS server that
will act as the authoritative name server for
that zone
• Secondary zone: created on other DNS servers
– Acts as backups to the primary zone
• Reverse lookup zone: creates pointer records
(PTR)
– Determine FQDN from the IP address
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.28 Two DNS servers with updating taking place
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.29 Reverse lookup zone
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Windows 2000 Server
• Can do cached lookups, primary and
secondary forward lookup zones, and reverse
lookup zones
• Active Directory—integrated zone
– Windows-only type of forward lookup zone
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Enter Windows
• DNS works well for any TCP/IP application that
needs an IP address for another computer, but
has a weakness
– A records are added to the DNS server manually
• Microsoft’s solved several issues by making:
– The NetBIOS name the DNS name
– The SMB protocol run directly on TCP/IP without
using NetBTC
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Samba
• UNIX/Linux systems tool for supporting SMB
• Makes non-Windows systems act like
Windows computers
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.30 Samba on Ubuntu (it’s so common that the OS
doesn’t even use the term in the dialog)
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Living With SMB
• Networks using SMB use two name resolution
systems
– SMB broadcasts to get the name when accessing
another computer’s folders or files
– The DNS server is used when accessing the
Internet
• SMB and DNS work together
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Organization into Groups
• Windows continues to support an old
organization of your computers into groups
• Three types of groups: workgroup, Windows
domain, and Active directory
• Workgroup
– A name that organizes a group of computers
– See workgroups in Network/My Network Place
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.31 Joining a workgroup
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.32 Two workgroups in Network folder
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Windows Domain
• Group of computers controlled by a computer
running Windows server
• Computers authenticate to the domain
controller
• Windows domain is not the same as a DNS
domain
• Windows domains now use DNS for their
names
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.33 Logging in to the domain
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Active Directory
• An organization of related computers that
shares one or more Windows domains
• All Active Directory Windows domain
controllers are also DNS servers
• All domain controllers are equal partners
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.34 If one domain controller goes down, another
automatically takes over
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Active Directory-Integrated Zones
• All of the domain controllers (which are all
also DNS servers) are equal
• The whole DNS system is not reliant on a
single DNS server
• The Active Directory contains the DNS servers’
DNS information
• Active Directory-enabled DNS servers send
DNS updates to each other
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Dynamic DNS
• DNS previously required manual updates
– Problematic as the numbers of Internet and
organization’s computers grew
• Dynamic DNS (DDNS)
– Enables a DNS server to talk to a DHCP server and
get IP addressing information on its clients
– Supported by all modern DNS servers
– Windows networks rely on DDNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Dynamic DNS (cont’d.)
• DNS Security Extensions (DNSSEC)
– Authentication and authorization protocol
– Implemented through extension mechanisms for
DNS (EDNS)
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Troubleshooting DNS
• The client is the source of most DNS problems
• DNS servers rarely go down
• If a DNS server is down, clients use a
secondary DNS server
• Symptom: “server not found” error
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.35 DNS error
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Troubleshooting DNS (cont’d.)
• Eliminating any local DNS caches
– On Windows, run ipconfig /flushdns
• ping the name of a well-known Web site
– Does it return an IP address?
– If not, ping an IP address of a known server
• If ping works with an IP address but not with
the Web site name, it is a DNS problem
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.36 Using ping to check DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Troubleshooting DNS (cont’d.)
• If the previous steps indicate a problem with
the DNS server, run the nslookup command
– Required proper permission level
– Enables DNS server queries
– Can make changes to how your system uses DNS
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Troubleshooting DNS (cont’d.)
• Running nslookup without parameters
gives:
– IP address and name of the default DNS server
• Error indicates primary DNS server is down or
client has the wrong IP for the DNS server
• Attach to any DNS server using the server
command followed by the IP address or the
domain name of the DNS server
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Troubleshooting DNS (cont’d.)
• Domain information groper (DIG)
– UNIX/Linux tool
– Similar to nslookup
– Runs noninteractively
– Ask it a question; it answers the question
– Tends to give a large amount of information
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Diagnosing TCP/IP Networks
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Diagnosing TCP/IP Networks
• Improper configuration causes most problems
• Ping anyone to whom you want to connect
• Regardless of what the user cannot connect
to, perform the same steps
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Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Diagnosing TCP/IP Networks (cont’d.)
• If one system behaves differently than others,
the problem is with the client
• Before starting steps on next slides: check the
network connections and protocols
Copyright © 2015 by McGraw-Hill Education. All rights reserved.
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Steps for Troubleshooting TCP/IP
1.
2.
3.
4.
5.
6.
Diagnose the NIC
Check the NIC’s driver; replace if necessary
Diagnose locally
Check IP address and subnet mask
Run netstat
Run netstat –s
Copyright © 2015 by McGraw-Hill Education. All rights reserved.
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Steps for Troubleshooting TCP/IP
(cont’d.)
7. Diagnose to the gateway
8. Diagnose to the Internet
Copyright © 2015 by McGraw-Hill Education. All rights reserved.
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.37 The net view command in action
Copyright © 2015 by McGraw-Hill Education. All rights reserved.
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.38 The netstat program in action
Copyright © 2015 by McGraw-Hill Education. All rights reserved.
Mike Meyers’ CompTIA Network+® Guide to Managing and
Troubleshooting Networks, Fourth Edition (Exam N10-006)
Figure 10.39 Using tracert
Copyright © 2015 by McGraw-Hill Education. All rights reserved.