Welcome to this months MCSE Help! feature. Over the
last few months I have been offering advice on each of the core examinations that must be
taken in order to gain your MCSE award. This month I am pleased to be able to start on the
electives, beginning with exam number 70-059 Internetworking TCP/IP with Microsoft Windows
As we all know, four out of the six examinations needed for obtaining MCSE are
non-optional, core subjects: Networking Essentials, Windows NT Server, Windows NT Server
in the Enterprise and either Windows 95 or Windows NT Workstation. Having passed these
four examinations, you must then decide upon which two elective examinations to take.
Almost everyone opts to take TCP/IP as one of their two electives, simply because almost
every network runs on TCP/IP and an understanding of TCP/IP is essential in order to
successfully install and administer other applications such as Internet Information
Server, SQL Server or Exchange Server. The TCP/IP exam is quite theoretical, so you must
be able to perform binary to decimal conversion and be able to understand very basic logic
operations. You cannot take any equipment into the room with you, but you will be provided
with a computer-based calculator with a binary and decimal conversion function.
The TCP/IP exam has 5 sections: Planning, Installation and Configuration, Connectivity,
Monitoring and Optimisation and Troubleshooting. As before, we will take a section at a
time, list the different subjects that you could get asked about in that section and then
give hints and tips on the types of pitfalls and traps you might come across in any one
particular question. This months article examines the first two of these sections.
The Planning Section
What to Revise
Name Resolution Methods, Multihomed Computers, Choosing a Subnet Mask, DNS & WINS, DNS
Aliases, Configuring DNS with WINS, WINS replication, LMHOSTS Options, Domain Functions
over Multiple Subnets, DHCP scopes and Reservations, SNMP, Determining Number of Host IDs,
Fault tolerance with DHCP, WINS records for Multihomed Computers, DNS Server Types.
1. Name Resolution Methods
Familiarise yourself with the following name resolution methods and in which circumstances
to use each one: HOSTS, LMHOSTS, DNS, WINS.
2. Multihomed Computers
To configure a multihomed computer, simply assign a valid IP address to each NIC (Network
Interface Card). To make the multihomed computer, enable IP forwarding from TCP/IP
properties. To enable dynamic configuration of the routing table, install the RIP for IP
3. Choosing a Subnet Mask
The factors to consider when choosing an appropriate subnet mask for your network are the
number of subnets, the class of IP address, the number of hosts on each subnet and future
4. DNS & WINS
You will be asked scenario-based questions about when and how to install and configure
these two services. Remember that you only need to install your own DNS server if you have
an intranet with either Unix or Macintosh computers on it. If your network is completely
Microsoft (and even if you are connecting to the Internet) you do not need to install your
own DNS server.
5. DNS Aliases
Sometimes you may have a host which requires multiple hostnames (for example if a host is
both the Web server and the mail server then it may be called www and mail). The standard
A record in DNS should only be used for one name per host. Subsequent names should be
configured using a CNAME record.
6. Configuring DNS with WINS
If you are using DHCP to assign IP addresses to hosts, or if you are using either Unix or
Macintosh computers alongside Microsoft computers using NetBIOS names, you may need to
configure the DNS server to query the WINS server. Because DNS is static, it cannot
resolve dynamically changing IP addresses that may occur when using DHCP. Similarly, being
for Host names only, it cannot resolve NetBIOS names. To allow WINS resolution, configure
the properties of the zone on the primary DNS server.
7. WINS replication
It is recommended that you have more than one WINS server on your internetwork to provide
fault tolerance for name resolution. If you do this, you must replicate their databases to
each other in order for them to have a full list of name-to-ip-address data. If you
configure a WINS server as a pull partner it is configured to collect data from the other
WINS server on a schedule. If you configure a WINS server as a push partner it is
configured to give data to the other WINS server once a set number of updates have
occurred to its database. You may get a scenario-based question regarding this.
8. LMHOSTS Options
There are several entries that you can make in an LMHOSTS file:
||Preloads the specified entry into the cache for
||Informs the system of the name of a domain
||The path to and name of another LMHOSTS file to
be parsed as if it were part of the local one
||Allows multiple #INCLUDEs to be grouped
||Used in conjunction with #BEGIN_ALTERNATE
9. Domain Functions over Multiple Subnets
If your domain spans multiple IP subnets, it is strongly recommended that you deploy WINS
to allow domain functions to operate successfully. If you elect to use LMHOSTS instead,
you will need to configure each LMHOSTS file with certain entries in order to be able to
support domain browsing, log on and synchronisation.
||Each Backup Browser must have a #PRE #DOM: entry
for the Master Browser. The Master Browser must have a #PRE #DOM: entry for each of the
||Each workstation on a subnet that has no domain
controllers must have a #PRE #DOM: entry for at least one domain controller
||Each Backup Domain Controller must have a #PRE
#DOM: entry for the Primary Domain Controller. The Primary Domain Controller must have a
#PRE #DOM: entry for each of the Backup Domain Controllers
For fault tolerance it is recommended that each BDC and/or Backup browser also have
entries for the other BDCs and Backup browsers in case the PDC or Master Browser goes
offline and another one is promoted to that role.
10. DHCP scopes and Reservations
Certain hosts (such as routers used as default gateways) are referenced from other hosts
by their IP address. If you are using DHCP to assign IP addresses, you must make sure that
the address assigned to such hosts is always the same. To reserve an IP address for a host
you must specify both the IP address and the hardware (or MAC) address of the host.
To provide SNMP support over TCP/IP you need to install the SNMP service.
12. Determining Number of Host Ids
The factors to consider when determining the total number of hosts IDs required on a
network are one per host and one per router interface.
13. Fault tolerance with DHCP
It is recommended that you have at least two DHCP servers for fault tolerance. Assign 75%
of the total number of IP addresses for the local subnet to a scope on the local DHCP
server and assign the other 25% to a scope on a remote DHCP server. Repeat this for each
subnet and configure a DHCP relay agent for each subnet. In this way, if the local DHCP
server fails, there will be at least some IP addresses available for assignment.
14. WINS records for Multihomed Computers
Only one IP address can be automatically registered by a WINS client. If you have any
multihomed computers, you will need to add manual records for all but the first IP
address. The record type to use is called MULTIHOMED.
15. DNS Server Types
A Primary DNS server maintains the read/write master copy of a zone file.
A Secondary DNS server maintains a read-only backup copy of a zone file
A Cacheing-Only DNS server does not maintain a copy of a zone file and is used to cache
previous requests for fast resolution. Cacheing-Only DNS servers are often configured as
DNS Forwarders, which means that they can query other DNS servers for out-of-zone
The Installation and Configuration Section
What to Revise:
SNMP Trap Configuration
DNS Record Types
1. TCP/IP Printing
To allow Unix workstations to print to a printer using Windows NT, install the TCP/IP
Printing service then share the printer as usual. The three components installed with the
TCP/IP Printing service are:
LPD The print server service (or daemon)
LPR The client service that allows print jobs to be submitted to a print daemon.
LPQ - The client service that allows the print queue to be remotely queried.
2. DNS Resolution
The file used to resolve host names via the Internet root servers is called DNS.CACHE
The most essential part of this section (and perhaps of the entire exam) is a thorough
familiarity with subnet masks. You will be given several questions (some scenario-based)
on custom subnet masks. The tables for classes A, B and C of address are shown below. You
can work it out from scratch in the exam, but I recommend memorising the tables and
replacing them onto paper as soon as you get into the exam room that way you
cant go wrong. Memorising the tables is not hard, as the first column is doubled +2
from the top down and last column is the reverse (doubled and add 2 from the bottom up).
|No of Subnets
||No of Bits
||Hosts per Subnet
|No of Subnets
||No of Bits
||Hosts per Subnet
|No of Subnets
||No of Bits
||Hosts per Subnet
4. Router Configuration
To configure routers manually use the ROUTE ADD command. The syntax for this command is:
ROUTE ADD [destination net ID] MASK [netmask] [gateway address]
5. DHCP Options
Global Options are options configured for all scopes on the DHCP server. This would
commonly include WINS Server, Node Type and DNS Server settings
Scope Options are options configured for a specific scope only. This would commonly be the
6. SNMP Trap Configuration
You need to know the community name and the IP address of the SNMP management station in
order to configure NT to send traps.
7. DHCP Configuration
Each scope can be configured with its own lease duration. A longer lease duration is less
efficient with IP addresses but requires less network traffic.
A DHCP relay agent must be present on any subnet containing DHCP clients that does not
have a local DHCP server present.
If you are configuring DHCP to assign the IP address of a WINS server to its client, you
must also configure it to assign a node type. The recommended node type is H, which
corresponds to a hexadecimal value of 0x8. The node types are described below.
||Broadcasts to resolve NetBIOS names
||Contacts a WINS server to resolve NetBIOS names
||Mixed uses a broadcast followed by a WINS
Server if the broadcast was unsuccessful
||Hybrid uses a WINS Server followed by a
broadcast if the WINS Server was unsuccessful
8. DNS Record Types
Although there are many types of DNS records that can be added to a zone file, the only
ones that you are likely to be tested on are the following:
||Standard host name
||IPv6 host name
||Alias (for hosts with multiple names)
||SMTP mail server
||Inverse resolution record
Richard Adams is an executive technical director for
Additional Resources, an IT training company