Contents:
This section explains the processes involoved
with Setting Up the Server on a Network, and features the following
topics:
Click Here to
go to Network Configuration
Part Two, for instructions on Creating
Startup Configuration Files.
The information in this section is intended for
system administrators with access to privileged commands and assumes
a knowledge of the TCP/IP protocol and UNIX system administration.
This section describes how to specify server
characteristics for setup on a TCP/IP network.
Topics discussed
are:
Defining
the Internet Address and Subnet Mask
Use the DEFINE INTERNET ADDRESS command to define
the server's Internet address. Then reinitialise the Communications
Server for the new Internet address to take effect. The following example
shows how to define the Communications Server's Internet address as
123.4.5.6, define the subnet mask as 255.255.0.0, and reinitialise the
Communications Server.
Local 1>> DEFINE INTERNET ADDRESS 123.4.5.6 SUBNET
MASK 255.255.0.0.
Local 1>> INITIALIZE SERVER DELAY 0
You don't need to specify a subnet mask if subnet
masks are not being used on the network. However, if you don't specify
a subnet mask, one is automatically assigned to the Server based on
the server's defined Internet address. For example, if you entered a
Class C Internet address, the subnet mask 255.255.255.0 is automatically
assigned to the Server.
Use the SHOW INTERNET command to display the
current Internet address and subnet mask.
Determining
the Internet Address from the Network
If you do not define the Internet address locally,
the Communications Server attempts to determine it over the network,
first by using BOOTP and, failing that, by using RARP and DHCP. BOOTP
and RARP are TCP/IP network protocols in which the Communications Server
broadcasts its Ethernet address, and the network host returns its Internet
address.
Note that with BOOTP the network
host can return the name of a default startup configuration file to
be downloaded to the Communications Server using TFTP. See 'Startup
Configuration Files' later in this section. Refer to your TCP/IP network
host documentation for details about DHCP, BOOTP and RARP.
Go to TCP/IP Topics
Manipulating
the ARP Table
The Address Resolution Protocol (ARP) matches
an Internet address with an Ethernet address. For example, if the Communications
Server wants to send an Ethernet packet to a remote host, and the remote
host's Ethernet address is not in the server's ARP table, the Communications
Server sends an ARP broadcast to all hosts on the network. A remote
host sends an ARP response with its Ethernet address to the Communications
Server. The server enters the remote host's Ethernet address into its
ARP table, and sends the Ethernet packet and subsequent packets directly
to the remote host.
You can change, display, and clear entries in
the Communications Server's ARP table. Refer to the following commands
in the EasyServer II Command Reference
Manual:
SET/DEFINE/CHANGE INTERNET ARP ENTRY
LIST/SHOW INTERNET ARP ENTRY
PURGE/CLEAR INTERNET ARP ENTRY
Setting
Up an Internet Gateway
The purpose of an Internet gateway is to provide
a way to interconnect networks or subnetworks. Information can be forwarded
to other networks that would otherwise be inaccessible. Gateways route
packets to the appropriate host or to other gateways until the packets
can be delivered to the final destination.
The Communications Server learns about gateways
on the network through the Internet Control Message Protocol (ICMP),
redirect messages, and route protocols such as the Routing Information
Protocol (RIP). The information is stored in the operational database
only and is lost when the Communications Server is powered off.
The Communications Server also provides a local
gateway table. This table is useful for defining a default gateway or
for accessing particular gateways that do not support ICMP or are using
a routing protocol other than RIP.
To define a default gateway, use the CHANGE INTERNET
GATEWAY command. The following example shows how to set up the Internet
gateway 123.4.5.7 as the default gateway, and also allow access to any
other network accessible to that gateway. (Refer to the SET/DEFINE/CHANGE
INTERNET GATEWAY command in the EasyServer
II Command Reference Manual.)
Local 1>> CHANGE INTERNET GATEWAY 123.4.5.7 NETWORK
ANY
To determine the current status of your gateway
table, use the SHOW INTERNET GATEWAY command.
Go to TCP/IP Topics
Creating
an Internet Host Table
An Internet host table maps host names to Internet
addresses, allowing you to access remote hosts using a host name or
alias instead of an Internet address. You can create a host table on
the Communications Server.
Refer to the SET/DEFINE/CHANGE INTERNET HOST command
in the EasyServer II Command Reference
Manual. Refer also to the next section, 'Using the Domain
Name System' for an alternate method of mapping host names to Internet
addresses.
Using
the Domain Name System (DNS)
The Domain Name System (DNS) is an online distributed
database system used to map host names to Internet addresses. DNS servers
in a TCP/IP network implement a hierarchical namespace that allows sites
freedom to assign host names and Internet addresses. Setting up a DNS
server replaces the need to create local host tables in the Communications
Server.
Using Web Configuration.
Invoke the Server's setup utility by entering
its IP address in a network-connected web-browser, (i.e. http://123.456.789.001).
When the Setup front page is displayed:
Step 1.
Press the 'Setup' button. Specify a valid
user name and password, if prompted.
Step 2.
Select the 'Server' (general server setup)
hyperlink from the main Setup screen.
Step 3.
Select the 'Domain Name Services' hyperlink
from the Setup Server screen.
Step 4.
Specify the configuration server name(s)
and server address(es) to be mapped.
Step 5.
Press the Configure button when ready.
The input parameters are implemented immediately. The setup program
now confirms that the input has been accepted by displaying the Configuration
Results screen.
Using Command Line Configuration.
To set up a DNS server, enter the Internet address
of the DNS server in the Communications Server's DNS table and specify
the Communications Server's domain name. Use the CHANGE INTERNET NAMESERVER
command to add the DNS server's name and Internet address to the Communications
Server's DNS table, for example:
Local 1>> CHANGE INTERNET NAMESERVER enghost
ADDRESS 123.4.5.8
The following example shows how to use the CHANGE
INTERNET NAME RESOLUTION DOMAIN command to specify the domain name.
Local 1>> CHANGE INTERNET NAME RESOLUTION DOMAIN
eng.company.com
To display the Communications Server's current
DNS information, use the SHOW INTERNET NAME RESOLUTION command.
Specifying
Dedicated or Preferred Services
A dedicated service is most useful for inexperienced
users who are unfamiliar with Communications Server commands, and users
who will always use one particular service exclusively. Specifying a
dedicated service has some security benefits too; it keeps users from
accessing the Communications Server command set. And users are restricted
to one session; they cannot use the Break key to return to local mode
on the Communications Server.
The following example shows how to specify Telnet
as the default protocol of port 3 and server1 as the dedicated host.
Local 1>> CHANGE PORT 3 DEFAULT PROTOCOL TELNET
Local 1>> CHANGE PORT 3 DEDICATED SERVER1
When specifying a dedicated service for a port,
the dedicated service you choose must be compatible with the default
protocol of the port.
To establish a session with a dedicated service,
press <Enter>; you don't have to log in to the Communications Server
or type any Communications Server commands.
A preferred service is most useful for more experienced
users who are familiar with Communications Server commands, and users
who will use one particular service frequently, but might occasionally
use other services.
The following example shows how to specify Telnet
as the default protocol of port 3 and docdock as the preferred host.
Local 1>> CHANGE PORT 3 DEFAULT PROTOCOL TELNET
Local 1>> CHANGE PORT 3 PREFERRED DOCDOCK
To establish a session with a preferred service,
log in to the Communications Server and use the CONNECT/OPEN command.
However, if AUTOCONNECT is enabled, you are connected automatically
to the preferred service when you log in to the Communications Server.
You can use the Break key to return to local mode on the server.
Refer to the following commands in the EasyServer
Command Reference Manual for more information:
CONNECT/OPEN
SET/DEFINE/CHANGE PORT DEDICATED
SET/DEFINE/CHANGE PORT DEFAULT PROTOCOL
SET/DEFINE/CHANGE PORT PREFERRED
