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FTP
Services for IntranetWare
A supplement to Novell's CNE Study Set -- IntranetWare/NetWare 4.11
by David James Clarke, IV
Featuring:
The final component in IntranetWare's global electronic village is a bridge
to the sometimes understandable, always bizarre, world of Unix. FTP Services
for IntranetWare is a subset of the NetWare Unix Print Services 2.11 product
that allows TCP/IP clients to use FTP (File Transfer Protocol) to transfer
files within their corporate intranet or on the global Internet.
The FTP file transfer service consists of two modules:
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INETD.NLM -- is the FTP agent module. INETD monitors the IntranetWare TCP/IP
connection for incoming FTP requests. When a client initiates an FTP session,
it automatically loads FTPSERV.NLM.
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FTPSERV.NLM -- is the FTP server module. It provides the File Transfer
Protocol services to IntranetWare clients. The server allows up to 64 client
sessions to be active at one time. To optimize server memory, FTPSERV is
unloaded when no active FTP sessions exist.
At its most basic level, FTP Services for IntranetWare allows TCP/IP clients
to upload and download files using friendly browsers (such as Netscape
Navigator) or FTP clients. It's a fast and efficient protocol for routing
files through cyberspace.
In this section, we'll explore a number of important activities concerning
FTP Services:
Installing FTP Services
Configuring FTP Services
Using FTP Services
Troubleshooting FTP Services
Installing FTP Services
FTP Services is installed on the foundation of Novell's Internet Access
Server (NIAS). To support FTP Services for IntranetWare, your server must
be running NetWare 4.1 or later, have an additional 12MB of available RAM,
and provide 5MB of disk space on the SYS: volume. Additionally, the server
must be configured with TCP/IP (refer to the "Understanding TCP/IP" section
for more details).
Before installing the FTP server, you must load NFS name space and add
it to the volume where FTP files will be stored. You can accomplish this
entering the following commands at the file server console:
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LOAD NFS.NAM
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ADD NAME SPACE NFS TO SYS:
Replace SYS: with the name of the volume being configured for FTP Services
for IntranetWare. Also, make sure you add the LOAD NFS.NAM command to STARTUP.NCF.
Don't worry about the second command, because it is only executed once.
REAL WORLD
You can set up and access a Novell FTP Server without NFS name space,
but anonymous users won't be able to access FTP files. In this case, users
must authenticate with their NDS username and password. Then, the FTP Server
will dump them in their home directory, by default.
Now that the IntranetWare server is ready, it's time to install FTP
Services. (See Novell's CNE Study Guide for IntranetWare/NetWare 4.11,
pages 1170-1171.)
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During FTP installation, you'll have to make two important naming decisions:
DNS and NIS. The Domain Name System (DNS) is a distributed database that
provides host information. Using DNS, FTP Services can locate other computers
on the network. Network Information Services (NIS) is a distributed database
that provides common information such as user and group data. Using NIS,
FTP Services obtains information about users and groups from a central
location. During installation of FTP Services for IntranetWare, you'll
be asked where to store the DNS and NIS databases. Refer to the previously
mentioned book for more information.
Regardless of the option you choose, UNICON.NLM will be available for
database customization. Let's take a closer look.
Configuring FTP Services
Once the Novell FTP server has been installed, it's time to customize
file transfer options. This is accomplished this using the UNICON.NLM server
utility. UNICON allows you to:
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Manage the FTP Server
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Create FTP users
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Set File Permissions
The fun begins at the FTP server. To access the FTP Server Configuration
screen, load UNICON.NLM at the console. Then, select Manage Services, FTP
Server, and finally, Set Parameters. The various configuration options
for the Novell FTP server are described in Table 540SG-7. Once you're comfortable
with the FTP server settings, you can begin creating user accounts. Let's
start with Anonymous.
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Table 540SG.7: Novell FTP Server Configuration
Parameters
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| Server Parameter |
Description |
| Maximum Number
of Sessions |
The number of
FTP client sessions that can be active concurrently. Range: 1 to 64. |
| Maximum Session Length |
The length of time a client can
remain connected to the FTP server. Range: 0 to 99,999 minutes. |
| Idle Time Before
FTP Server Unloads |
The interval
between total client inactivity and FTPSERV.NLM unloading. Range: -1 to
60 minutes. |
| Anonymous User Access |
Allows or prevents anonymous logins
to the FTP server. |
| Default User's
Home Directory |
The directory
users will be placed upon logging into the FTP server. |
| Anonymous User's Home Directory |
The directory anonymous users
will be placed upon logging into the FTP server. |
| Default Name
Space |
Determines which
name space will be active when a client initiates a session. Range: DOS
or NFS. |
| Intruder Detection |
Enables or disables Intruder Detection.
Additionally, two related parameters allow you to specify the number of
unsuccessful login attempts allowed within a specified time period. |
| Log Level |
Determines what,
if any, information is written to a log file maintained on the FTP server.
Options include None, Statistics, Logins, and File. |
Once you've configured the FTP server, you'll need to enable an Anonymous
User account so clients can access FTP files. (See Novell's CNE Study Guide
for IntranetWare/NetWare 4.11, pages 1171-1173.)
TIP
In addition to Anonymous, you can create as many FTP users as you want.
Simply select the Username field under NetWare User Information within
UNICON.NLM.
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Once you've created FTP users, you need to make sure they have appropriate
permissions to FTP files. You can do this by using the View/Set File Permissions
menu within UNICON.NLM. You can customize any of the following three NFS
permissions for Users (U), Groups (G), and/or Other (O):
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read (r) allows the User, Group, or Other to see the contents of
the file and make copies of it.
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write (w) allows the User, Group, or Others to modify the contents
of the file or delete it.
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execute (x) allows the User, Group, or Others to execute the file.
Using FTP Services
The nice thing about FTP Services for IntranetWare is that it supports
any standard Web browser (such as Netscape Navigator). With Navigator,
you can browse, download from, and/or upload to the Novell FTP server.
All you need is the IP address.
As you can see in Figure 540SG-15, FTP directories appear as folder
icons, and files appear as documents. In this example, we've located the
Learning-Ware.com FTP server by typing the following URL into Navigator's
Location field:
ftp://206.127.205.130
Figure 540SG-15: Accessing FTP Services with Netscape Navigator
Netscape Navigator automatically logs you into the FTP server as the
special user named Anonymous. This dumps you into the default root directory
as specified by UNICON. If you'd like to access the FTP server using a
specific username, try the following syntax:
ftp://david@206.127.205.130
In this case, David is an NDS User object associated with a specific FTP
username and different default directory structure. In addition, if "David"
has a password, you'll be prompted to enter it. This way, you can restrict
certain areas of the FTP server to specific authorized users.
Once you've accessed an FTP server, you'll notice that all directories
and files appear as underlined hyperlinks. Furthermore, your browser cursor
will become a "hand" when you approach the link. This means you can do
two things to FTP Server objects:
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Download the files -- Click the document hyperlink, and Navigator offers
you two choices. Choose Save as and identify a local directory. You can
also click on Folder Lengths to access a different subdirectory structure.
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Launch an application -- You can also launch applications directly from
the FTP server by clicking the link and identifying a local associated
application.
Finally, you can upload files to an FTP server using Netscape Navigator.
Simply navigate to the destination FTP directory and choose Upload from
the File menu, browse to the file you want to upload, and double-click
it.
As you can see, FTP Services for IntranetWare integrates seamlessly
into your native Windows-based browser. It's a fast and efficient way to
publish documents and/or make them available as binary files. Now, let's
finish our journey through IntranetWare's virtual directory structure,
with a quick look at troubleshooting.
Troubleshooting FTP Services
Like Novell's Web Server, the IntranetWare FTP server is robust and
reliable; however, it's not fool-proof. Most FTP-related problems deal
with communication and configuration errors. Oh, yeah, there are user errors,
too, of course. Let's take a quick look at the five most common FTP problems:
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Network failure
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FTP Server not running
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Overloaded FTP Servers
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FTP configuration errors
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User error
Network Failure
If you're having problems accessing a specific FTP Server, consider
using WINPING.EXE to verify the continuity of network communications. This
utility is explained earlier in the "IPX/IP Gateway" section.
If the PING test fails, the FTP problem is probably network-related.
FTP Server Not Running
If you determine that the network is running fine, your FTP server may
be down. Verify its cyber-existence by performing the following steps at
the FTP server:
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Load UNICON.NLM at the server console.
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From the main menu, select Start/Stop Services.
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Verify that the FTP server is present in the Running Services List. If
it is missing, press Ins then select FTP Server from the Available Services
list.
Overloaded FTP Server
Most FTP servers have a CNE-imposed limit on the maximum number of concurrent
client connections. This is all part of the delicate balance between FTP
server availability and performance.
If you attempt to connect to an FTP server that has no client sessions
available, you'll receive one of a variety of error messages:
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Netscape Navigator - "FTP Server has no available connections. Try
again later."
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LAN Workplace for DOS - "I/O Error - connection lost."
In addition to unavailable client connections, high network traffic can
also overload FTP servers. If file transfer performance is extremely slow,
you may consider increasing the speed of Internet/intranet links or available
RAM on the server.
FTP Configuration Errors
FTP configuration errors can occur either on the client or on the server.
An improperly configured FTP client can prevent the user from connecting
to FTP servers. First, ask yourself, "Is the client TCP/IP protocol stack
loaded?" If so, make sure it's configured properly with the correct IP
address, subnet mask, and default router information. Finally, make sure
the client NIC is configured for the appropriate TCP/IP frame type. You
can verify that the client is communicating properly by performing a PING
test with WINPING.EXE or Windows 95's built-in WINIPCFG.
If a user is unable to connect to a particular FTP server, however there
might be a problem with the server configuration. First, make sure the
user isn't restricted by checking the SYS:ETC\RESTRICT.FTP file. If a user
is able to access the FTP server but unable to download a particular file,
you may have an attribute problem. Make sure the file is not flagged with
the Read Only file attribute. Also, shared FTP documents may often require
the Sharable attribute as well.
User Error
If the problem isn't with the network, FTP server, or client, there's
only one candidate left -- the user. As you can imagine, many problems
result from inexperienced or improperly trained FTP users. Here's a quick
list of questions to ask complaining FTP users:
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Was the FTP server name specified correctly?
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Did the user attempt to use a DNS name when an IP address was required?
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Was the proper account name specified when the user attempted to log into
the FTP server? (In some cases, especially with FTP Services for IntranetWare,
users must provide their full distinguished NDS name.)
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Was the proper password specified when the user attempted to log into the
FTP server?
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If a file transfer failed, did the user have the appropriate rights to
create a file in the destination directory?
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If all else fails, scrap cyberspace and buy the user a typewriter!
This completes our discussion of file transfer in IntranetWare's global
electronic village. Remember, FTP Services for IntranetWare fits very well
into our three-component cyberspace model. With this component, files appear
as hyperlink documents using the same Novell Web Server browser. In fact,
all three components work in synergy to provide transparent access to the
information superhighway.
Here's how it works:
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TCP/IP Protocol -- provides the "concrete" of the information superhighway.
This is the protocol that routes messages between clients and services.
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IPX/IP Gateway -- is the "bridge" between the information superhighway
and distributed Web sites. Through this bridge, IPX-based clients can cruise
the IP-based highway and access Novell Web or FTP servers.
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The Novell Web Server -- publishes multimedia, HTML documents from an IntranetWare
server. These are the "buildings" that give our global electronic village
form and function.
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FTP Services for IntranetWare -- is a second kind of cyberspace "building"
that provides distributed TCP/IP clients with a virtual directory structure.
Using FTP, IntranetWare clients can download files, upload documents, or
launch applications from anywhere on the Net.
In the introduction, we described IntranetWare as the foundation of Novell's
global electronic village. Hopefully, now you have an appreciation for
how it works. This is by far the most synergized intranet/Internet solution
ever conceived.
Surf's up!
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