1.7 Summarize DNS concepts and its
The most common type of DNS record is a Host record (also
called an A record). In the Internet, a Host record is used
to associate a domain name (FQDN – Fully Qualified Domain
Name) with an IP address.
An MX record stores the IP
address of your SMTP server, so e-mail clients can determine
where a message should be sent. They perform a DNS query
against a domain's MX record to get the IP address of the
organization's SMTP server.
An Alias record's job is to associate an alternate name
with a computer for which there is already a Host record.
For example, suppose that the host record for relevant looked
Relevant Host (A) 220.127.116.11
Alias record is like a redirect. For example, you have
a site mydomain.com. However, someone enters www.mysite.com,
You want him or her to be directed to the web.mysite.com.
Since there is no server on the network named "www," set
up an Alias record that associates www with mysite.com.
The Alias record looks something like this:
www Alias (CNAME) mysite.com
MAC address record is not associated with DNS server
1.8 Given a scenario, implement the
following network troubleshooting methodology
Given below is the sequence of steps recommended to be
following is solving a network problem:
1. Information gathering - Identify symptoms and
2. Identify the affected areas of the network
3. Determine if anything has changed
4. Establish the most probable cause
5. Determine if escalation is necessary
6. Create an action plan and solution identifying
7. Implement and test the solution
8. Identify the results and affects of the solution
9. Document the solution and the entire process
Indirect enquires are usually not a recommended practice.
1.9 Identify virtual network components
Virtual Switch is a software program that allows
one virtual machine to communicate with another. It
can intelligently direct communication on the network
by inspecting packets before passing them on.
Virtual Server is a server which is shared by multiple
website owners. Each owner can use use and administrate
With virtual desktops, a user's data is stored in
a data center rather than on an office computer's hard
drive. By providing authentication credentials, a secure
connection can be established between the centralized
repository of user data and that user's device , thus
allowing the user to remotely access her document.
PBX A Private Branch Exchange (PBX) is a privately
owned telephone switch traditionally used in corporate
telephony systems. Although a PBX is not typically considered
a VoIP device, it can connect into a VoIP network through
In Naas (Network as a Service), the service provider
offers services like e-mail and DNS for use by the clients.
In SaaS (Software as Service), typically access is provided
to a software application.