Monday, August 27, 2012

Where Has Darril Gibson Been?

You may have noticed that Darril Gibson hasn't been posting much or been active on many forums lately. I thought I'd give you an idea of what's up.

I attended Jack Canfield's seven day Breakthrough to Success program from Aug 19th through 25th in Scottsdale, Arizona. Combined with full days, a day of travelA there and a day of travel back it was a packed week.

However, it was fabulous. I had a great time and left with some clear cut goals on actions I'll be taking in the future. Among other things, I'll be finishing my book You Can Do Anything - Three Simple Steps to Success for High School Students.

With about 400 other people attending, I was also able to connect with a wide array of very successful people. As one of dozens of examples, I met Kathy Anderson, author of the award winning book Change Your Shoes, Live Your Greatest Life and during a lunch with her, I learned how to create my own publishing company.

As a follow up, I am in the process of creating a publishing company. It's called YCDA, LLC (short for You Can Do Anything). I'll use this company to self-publish books such as the CompTIA Security+: Get Certified Get Ahead: SY0-301 Study Guide so that I can reach a wider audience than I've been able to do with just Amazon. I can also use this company to publish my new book You Can Do Anything - Three Simple Steps to Success for High School Students, if a publisher doesn't step up to take it on.

Jack Canfield is a dynamic speaker and presenter and did an awesome job. While most people know him as one of the co-author's of the Chicken Soup for the Soul series, he's also a very successful coach, corporate trainer, keynote speaker, and author of The Success Principles: How to Get from Where You Are to Where You Want to Be.

I was first exposed to these principles about five years ago and know that implementing these principles helped me move from an unpublished author to a full-time writer that has authored or co-authored more than 25 books.

Another participant mentioned that he picked up the book while staying at a homeless shelter. The ideas resonated with him and he is now the owner of his own business.

Despite Jack Canfield's huge successes, he's really a friendly down-to-earth person. I was able to talk to him one-on-one when the two of us shared an elevator and walk to the conference room one day. I also attended a luncheon with him and some other participants that are part of the Bestseller Blueprint program.

I spent last week trying to catch up on "must do" items and am finally starting to get back into the swing of things.

Currently, I'm finishing up the CompTIA A+ Training Kit (Exam 220-801 and Exam 220-802) which is in the last stages of editing. I've put a lot of time and effort into this book and hope that will help many people take and pass the new A+ exams the first time they take it. I'm also finishing up the writing of the CISSP Rapid Review book. This is intended to be a late stage review book that people can use to review key material to see if they're ready for the CISSP exam.

Next on the horizon is a book on Windows 8 for the 70-687 exam, Configuring Windows 8. I'm looking forward to writing this.

At any rate, despite being off the grid for the past couple of weeks, Darril Gibson is back on the grid and will be posting more.

Tuesday, August 7, 2012

Network+ Command Line Tools Pt 2

If you're planning on taking the Network+ exam soon, you may want to review the command line tools such as tracert, nslookup, dig, and route used to troubleshoot connectivity. You don't have to know every switch related to these command line tools but you should have a good idea of their overall purpose. This blog doesn't provide all the details about these command line tools, but combined with part 1 it should give you enough for the Network+ exam.

Many people are using the Microsoft Windows Networking Essentials book to help prepare for the Network+ exam. The book was actually written for the MTA 98-366 Networking Fundamentals exam and is helping a lot of people take and pass it. Combined with the CompTIA Network+ N10-005 Practice Test Questions (Get Certified Get Ahead) book, people have told me they have also passed the Network+ exam the first time they took it.
Realistic Practice Test Questions for the Network+ exam.
CompTIA Network+ N10-005 Practice Test Questions (Get Certified Get Ahead)

Practice Test Questions

Q. You want to determine how long it takes a packet to get to and from a router. What can you use?

A. Ipconfig
B. Traceroute
C. Nslookup
D. Netstat

Answer at end

You are running a Linux system and need to verify whether you can reach a DNS server. Which of the following commands can you
use?

A. Dnslookup
B. Dig
C. Route
D. Netstat

Answer at end
Realistic practice test questions for the Network+ N10-005 exam
Available through LearnZapp on your mobile phone

Tracert/Traceroute Command Line Tools

The tracert (or traceroute) command identifies the IP address of each of the hops between two systems. Each hop is a router and the round trip time (RTT) shows how long it takes to get to and from the two systems. Try it with this command:

tracert GetCertifiedGetAhead.com

Results

Tracing route to GetCertifiedGetAhead.com [174.122.52.195] over a maximum of 30 hops:
1 <1 em="em" ms="ms">
2 7 ms 7 ms 7 ms 10.114.228.1
3 8 ms 7 ms 11 ms 68.110.110.13
4 8 ms 7 ms 7 ms 172.212.418.165
5 8 ms 9 ms 7 ms 172.212.160.132
6 19 ms 7 ms 7 ms 68.110.18.157
7 13 ms 13 ms 13 ms 68.111.4.133
8 25 ms 39 ms 25 ms xe-1-0-2.bbr02.eq01.wdc02.networklayer.com [50.197.16.21]
9 16 ms 14 ms 13 ms ae7.bbr01.eq01.wdc02.networklayer.com [173.192.118.194]
10 24 ms 24 ms 25 ms ae0.bbr01.tl01.atl01.networklayer.com [173.192.118.153]
11 45 ms 45 ms 45 ms ae13.bbr02.eq01.dal03.networklayer.com [173.192.118.134]
12 44 ms 45 ms 48 ms po32.dsr01.dllstx3.networklayer.com [173.192.118.229]
13 44 ms 46 ms 45 ms te2-1.dsr01.dllstx2.networklayer.com [70.187.255.66]
14 45 ms 44 ms 45 ms te3-1.car11.dllstx6.networklayer.com [70.187.254.218]
15 44 ms 45 ms 46 ms stats.carnation.arvixe.com [174.122.152.195]

Trace complete.
Realistic practice test questions for the Network+ N10-005 exam
Available through LearnZapp on your mobile phone

Nslookup Command Line Tool

The name server lookup (nslookup) command is used to verify that a Domain Name System (DNS) server can resolve host names to IP addresses. It can also verify that a DNS server can resolve fully qualified domain names (FQDNs) to an IP address. A fully qualified domain name includes the host name and the domain name and is commonly used to locate web sites.

The basic syntax is:

nslookp GetCertifiedGetAhead.com

Results

Server: cdns1.cox.net
Address: 68.105.28.11
Non-authoritative answer:
Name: GetCertifiedGetAhead.com
Address: 174.122.52.195

Dig Command Line Tool

The domain information groper (dig) command is a command line tool used to query DNS servers. It provides similar functionality as nslookup but is only available on Linux/Unix-based systems. It is not available on Windows systems. You can use dig to query DNS servers to very that the DNS server is reachable, and to verify that a DNS server can resolve names to IP addresses.

Arp Command Line Tool

Each time a computer needs to communicate with a system on the same network it uses the Address Resolution Protocol (ARP) to resolve the IP address to the media access control (MAC) address. Information gathered from ARP is stored in the ARP cache and can be viewed with the arp command. The basic syntax is:
arp -a

Partial results:

Interface: 192.168.1.129 --- 0xa
Internet Address Physical Address Type
192.168.1.1 68-7f-74-ae-8b-de dynamic
192.168.1.114 10-1f-74-03-99-7d dynamic
192.168.1.122 00-90-a9-b3-b2-1d dynamic

Route Command Line Tool

You can use the route command to show or manipulate the routing table on a computer. The following command will show the routing table:

route print

Partial results

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.129 10
127.0.0.0 255.0.0.0 On-link 127.0.0.1 306
127.0.0.1 255.255.255.255 On-link 127.0.0.1 306
127.255.255.255 255.255.255.255 On-link 127.0.0.1 306
192.168.1.0 255.255.255.0 On-link 192.168.1.129 266
192.168.1.129 255.255.255.255 On-link 192.168.1.129 266
192.168.1.255 255.255.255.255 On-link 192.168.1.129 266

What's next after the Network+ exam?
Pass the Security+ exam the first time you take it with the
CompTIA Security+: Get Certified Get Ahead: SY0-301 Study Guide

Practice Test Questions with Answers

These practice test questions came from CompTIA Network+ N10-005: Practice Test Questions (Get Certified Get Ahead). This resource includes 275 realistic practice test questions and over 175 flash cards to help test your readiness so that you can take and pass the exam the first time you take it. It's available for only $9.99 in the Kindle version and you can download free Kindle apps from Amazon for just about any platform.

Q. You want to determine how long it takes a packet to get to and from a router. What can you use?

A. Ipconfig
B. Traceroute
C. Nslookup
D. Netstat

Answer: B is correct. The traceroute command shows the round trip time (RTT) for each router (or hop) in the path it traces.

A is incorrect. Ipconfig shows TCP/IP configuration information but not the RTTs.

C is incorrect. Nslookup can query DNS servers for name resolution, but doesn’t list the RTTs for routers.

D is incorrect. The netstat command shows network statistics and open connections.

--

You are running a Linux system and need to verify whether you can reach a DNS server. Which of the following commands can you
use?

A. Dnslookup
B. Dig
C. Route
D. Netstat

Answer: B is correct. The dig command (sometimes called domain information groper) is a utility available on Linux/Unix-based systems that can query domain name system (DNS) servers for specific records.

A is incorrect. Nslookup (not dnslookup) is the precursor to dig on Unix/Linux based systems and is available on Windows systems to query DNS servers.

C is incorrect. The route command allows you to view and manipulate the routing table on a system, including the default gateway.

D is incorrect. Netstat can identify open ports a system is listening on, and list other protocol statistics.

Summary

You should have a basic understanding of command line tools when preparing for the Network+ exam. This blog covered the tracert, traceroute, nslookup, dig, arp, and route and part 1 covers ping, ipconfig, and ifconfig commands and . You may also like to check out these Network+ blogs and other links:
Good Luck!

Network+ Command Line Tools Pt 1

If you're planning on taking the Network+ exam soon, you may want to review the command line tools such as ping and ipconfig used to troubleshoot connectivity. You don't have to know every switch related to these command line tools but you should have a good idea of their overall purpose. This blog doesn't provide all the details about these command line tools, but combined with part 2, it should give you enough for the Network+ exam.

Many people are using the Microsoft Windows Networking Essentials book to help prepare for the Network+ exam. This book was actually written for the MTA 98-366 Networking Fundamentals exam and is helping a lot of people take and pass it. Combined with the CompTIA Network+ N10-005 Practice Test Questions (Get Certified Get Ahead) book, many people have told me they have also passed the Network+ exam the first time they took it.
Realistic Practice Test Questions for the Network+ exam.
CompTIA Network+ N10-005 Practice Test Questions (Get Certified Get Ahead)

Practice Test Questions

Q. Which of the following commands can you use to test connectivity with a remote system?

A. Ping
B. Ipconfig
C. Arp
D. Route

Answer at end

Q. Using ipconfig, you see a computer has an IP address of 169.254.4.23 with a subnet mask of 255.255.0.0. What does this indicate?

A. DNS could not be reached
B. DHCP could not be reached
C. The default gateway could not be reached
D. The computer’s firewall is enabled

Answer at end

Q. A system has an incorrect DNS entry in cache. What can you use to remove this entry?

A. Ipconfig /displaydns
B. Ipconfig /flushdns
C. Nslookup /removedns
D. Nslookup/flushdns

Answer at end
Realistic practice test questions for the Network+ N10-005 exam
Available through LearnZapp on your mobile phone

Ping Command Line Tool

Ping is a basic command used to test connectivity for remote systems. You can also use it to verify the TCP/IP stack is installed and  working correctly on a system, test the network interface card (NIC), and verify valid host names can be resolved to IP addresses. Ping works at the network layer of the OSI model.

Use Ping to Check Connectivity with Remote System

If you know the IP address of a remote system, you can use ping to verify connectivity. For example, you can use ipconfig to identify the  default gateway and then use ping to verify that you can reach the default gateway. The basic syntax is:

ping 192.168.1.1

Results:

Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms ttl="64</em">
Reply from 192.168.1.1: bytes=32 time<1ms ttl="64</em">
Reply from 192.168.1.1: bytes=32 time<1ms ttl="64</em">

Ping statistics for 192.168.1.1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 1ms, Average = 0ms

On Windows systems, ping sends out four ping requests and if the other system is operational, it receives four replies. On Linux/Unix based systems, the ping will continue until you press the CTRL + C keys. If you want ping to work like the Linux systems, you can use the -t switch like this:

ping -t 192.168.1.1

Check Name Resolution with Ping

You can ping either the hostname of a system, or an IP address. For example, the following two commands will achieve the same result:
  • ping blogs.getcertifiedgetahead.com
  • ping 174.122.52.195
The first command will first resolve the name blogs.getcertifiedgetahead.com to the IP address of 174.122.52.195 and it will then ping the IP address. The primary method used to resolve hostnames is with Domain Name System (DNS) so ping will often query the DNS server.

ping blogs.getcertifiedgetahead.com

Result

Pinging blogs.getcertifiedgetahead.com [174.122.52.195] with 32 bytes of data:
Reply from 174.122.52.195: bytes=32 time=90ms TTL=118
Reply from 174.122.52.195: bytes=32 time=44ms TTL=118
Reply from 174.122.52.195: bytes=32 time=44ms TTL=118
Reply from 174.122.52.195: bytes=32 time=47ms TTL=118
Ping statistics for 174.122.52.195:
Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximate round trip times in milli-seconds:
Minimum = 44ms, Maximum = 90ms, Average = 53ms

Check TCP/IP Stack

You can ping the loopback address to verify that the TCP/IP stack is functioning. The command is:

ping 127.0.0.1

Result

Pinging 127.0.0.1 with 32 bytes of data:
Reply from 127.0.0.1: bytes=32 time<1ms ttl="128</em">
Reply from 127.0.0.1: bytes=32 time<1ms ttl="128</em">
Reply from 127.0.0.1: bytes=32 time<1ms ttl="128</em">
Reply from 127.0.0.1: bytes=32 time<1ms ttl="128</em">

Ping statistics for 127.0.0.1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms

If the TCP/IP stack is corrupt, you may be able to rebuild it with this command on Windows systems:

netsh winsock reset

Similarly, you can ping the local host with this command:

ping localhost

Pinging Power-PC [::1] with 32 bytes of data:
Reply from ::1: time<1ms em="em">
Reply from ::1: time<1ms em="em">
Reply from ::1: time<1ms em="em">
Reply from ::1: time<1ms em="em">

Ping statistics for ::1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms

It will resolve localhost to either the IPv4 loopback address of 127.0.0.1 or the IPv6 loopback address of ::1.

Verify the NIC

You can ping the IP address of the NIC installed in the computer to verify it is functioning. Use ipconfig to identify the IP address and then use ping followed by the IP address.

ping 192.168.1.129

Pinging 192.168.1.129 with 32 bytes of data:
Reply from 192.168.1.129: bytes=32 time<1ms ttl="128</em">
Reply from 192.168.1.129: bytes=32 time<1ms ttl="128</em">
Reply from 192.168.1.129: bytes=32 time<1ms ttl="128</em">
Reply from 192.168.1.129: bytes=32 time<1ms ttl="128</em">

Ping statistics for 192.168.1.129:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms

Ipconfig/Ifconfig Command Line Tools

The ipconfig command is a valuable basic command used to view the TCP/IP configuration. You can enter it without a switch and view the IP address, the subnet mask, and the default gateway. This allows you to easily verify the system has valid TCP/IP configuration information assigned. If it does, you can follow it up with the ping command to check connectivity.

ipconfig

Partial results

Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : getcertifiedgetahead.com
Link-local IPv6 Address . . . . . : fe80::20d4:3ff7:3f:de62%10
IPv4 Address. . . . . . . . . . . : 192.168.1.129
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1

One indication that a computer has a problem is an address starting with 169.254.y.z. This indicates the computer is a Dynamic Host Configuration Protocol (DHCP) client but is not able to reach a DHCP server. Instead, the computer has assigned itself an Automatic Private Internet Protocol Addressing (APIPA) address. APIPA addresses are in the range of 169.254.0.1 to 169.254.255.254.

The ifconfig command is similar to ipconfig except that it is used on is Linux/Unix-based systems. Ifconfig has more capabilities than ipconfig and can be used to configure the NIC in addition to listing the properties of the NIC.

Look At Everything with /All

The /all switch is valuable to identify all the details of the TCP/IP configuration. You can use this to identify the physical address or media access control (MAC) address of the computer, the address(es) of Domain Name System (DNS) servers, and the address if the DHCP server if the system is a DHCP client.

ipconfig /all

Partial results

Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : getcertifiedgetahead.com
Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
Physical Address. . . . . . . . . : 6C-62-6D-BA-73-6C
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv4 Address. . . . . . . . . . . : 192.168.1.129(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Sunday, July 29, 2012 5:13:43 PM
Lease Expires . . . . . . . . . . : Wednesday, August 08, 2012 5:13:42 AM
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 68.105.28.11
68.105.29.11
68.105.28.12
NetBIOS over Tcpip. . . . . . . . : Enabled

Remove DNS Cache Entries with /FlushDNS

The /flushdns is useful if the DNS cache has invalid entries. You can use the following command to view the DNS cache:

ipconfig /displaydns

Partial results

blogs.getcertifiedgetahead.com
----------------------------------------
Record Name . . . . . : blogs.getcertifiedgetahead.com
Record Type . . . . . : 1
Time To Live . . . . : 82644
Data Length . . . . . : 4
Section . . . . . . . : Answer
A (Host) Record . . . : 174.122.52.195

If there are invalid entries, use this command to remove them:

ipconfig /flushdns

Results

Windows IP Configuration
Successfully flushed the DNS Resolver Cache.
Pass the Security+ exam the first time you take it:
CompTIA Security+: Get Certified Get Ahead: SY0-301 Study Guide

Practice Test Questions with Answers

These practice test questions came from CompTIA Network+ N10-005: Practice Test Questions (Get Certified Get Ahead). This resource includes 275 realistic practice test questions and over 175 flash cards to help test your readiness so that you can take and pass the exam the first time you take it. It's available for only $9.99 in the Kindle version and you can download free Kindle apps from Amazon for just about any platform.

Q. Which of the following commands can you use to test connectivity with a remote system?

A. Ping
B. Ipconfig
C. Arp
D. Route

Answer: A is correct. The ping command will check connectivity with remote systems using either the name of the remote system or its IP address. It sends out an Internet Control Message Protocol (ICMP) Echo Request to another system. If the other system is operational and not blocking ICMP, it will respond with an ICMP Echo Reply. If you receive a response, it provides verification that the other system is operational. Many firewalls block ICMP traffic so if you do not receive a response, it doesn’t necessarily mean that the remote system is  not operational. It could be that ICMP was blocked. Try it by pinging a computer in your network.

B is incorrect. Ipconfig will show the TCP/IP configuration information for a system.

C is incorrect. Arp will show the MAC address to IP address mapping for systems in the Address Resolution Protocol (ARP) cache.

D is incorrect. Route allows you to view or manipulate the routing table within a system.

--

Q. Using ipconfig, you see a computer has an IP address of 169.254.4.23 with a subnet mask of 255.255.0.0. What does this indicate?

A. DNS could not be reached
B. DHCP could not be reached
C. The default gateway could not be reached
D. The computer’s firewall is enabled

Answer: B is correct. An address starting with 169.254 is an Automatic Private Internet Protocol Addressing (APIPA) address and is assigned to a Dynamic Host Configuration Protocol (DHCP) client when a DHCP server cannot be reached. Any time you see an APIPA address, you know the computer is a DHCP client and it didn’t receive a DHCP lease.

A is incorrect. Domain Name System (DNS) is used for name resolution and would not cause a system to have an APIPA address.

C is incorrect. The default gateway is assigned by DHCP to a DHCP client and an APIPA address indicates that the client was unable to reach a DHCP server. Also, APIPA addresses do not assign a default gateway.

D is incorrect. Enabling the computer’s firewall would not block DHCP traffic and would not prevent the client from receiving a DHCP address.

--

Q. A system has an incorrect DNS entry in cache. What can you use to remove this entry?

A. Ipconfig /displaydns
B. Ipconfig /flushdns
C. Nslookup /removedns
D. Nslookup/flushdns

Answer: B is correct. The ipconfig /flushdns command will remove any entries in the DNS cache that were resolved from a DNS server. Try it with the following three commands: ipconfig /displaydns, ipconfig /flushdns, ipconfig /displaydns

A is incorrect. The ipconfig /displaydns command shows the entries in the DNS cache.

C and D are incorrect. Nslookup can be used to verify that a DNS server can resolve a host name to an IP address but it does not support /removedns or /flushdns switches.

Summary

You should have a basic understanding of command line tools when preparing for the Network+ exam. This blog covered the ping, ipconfig, and ifconfig commands and part 2 covers tracert, traceroute, nslookup, dig, arp, and route. You may also like to check out these Network+ blogs and other links:
Good Luck!