|
Advertisement: Support LinuxWorld, click here! |
|
Advertisement: Support LinuxWorld, click here! |
Advertisement
|
|||||||||
| Linux and NetWare |
Linux on the LANIntegrating Linux and NetWare with Caldera's NetWare for LinuxSummaryBy William Wong |
 |
hough it's been getting a run for its money from the folks in
Redmond, when it comes to local area networking Novell NetWare remains king of the hill.
These days, adding a Linux client or server to a NetWare network has moved from the realm of the "technically possible" into the more headache-free world of the practical.
You can create own Linux-NetWare configuration or simply get the entire package ready to go in the form of Caldera's NetWare for Linux.
In this article, we'll take a look at four aspects of Linux NetWare support: protocols, directory services, and Linux as a client and a server, but first let's be clear about what you don't get with NetWare for Linux.
What's missing
Probably the most significant parts of NetWare not
supported by NetWare for Linux are Novell's NetWare loadable modules (NLMs)
and NetWare connections over IP (Internet Protocol).
Though Caldera's product doesn't yet support NetWare 5.0, it will probably be close to a year until most NetWare installations have upgraded to this newer version. By then, Caldera and Novell will have added the necessary features. In fact, NetWare 5.0 compatibility is pretty much inconsequential when you're talking about Caldera Linux clients though it does matter on the server side.
The major implication of these server-side inadequacies is that Linux as a server can only provide NetWare routing, file, and print services. Of course, Linux can still provide these and other services through alternate routes such as TCP/IP with the Apache Web Server and NetBIOS with the Samba server. In fact, Linux can add a lot of value to a NetWare network because of these additional services.
Free support for NetWare and IPX is available at a number of Internet FTP sites, including sunsite.unc.edu (see Resources). You can get a free download of Caldera's NetWare for Linux, but this version supports only three users when Linux is used as a server. If you need more client licenses, you must purchase the CD versions from Caldera or its distributors.
Protocols
While IPX was the first (and is still the foremost) NetWare protocol, IP is quickly taking over -- even on NetWare sites. In fact, NetWare 5.0 brings native IP
support to NetWare. At this point though, NetWare support on Linux is
limited to IPX.
However, Linux's support of only IPX isn't a major limitation because most NetWare networks still use -- and will continue to use -- IPX. Also, Linux is ideal for mixed-protocol environments, which is what most NetWare sites are moving to initially. Of course, the other protocol at these sites will be IP, which Linux supports in spades. In a typical configuration, Linux provides IPX access to file services, while the Apache Web Server uses IP. Users can edit Web pages directly on the server via the file services and access Web services using a standard browser.
Both NetWare's Router Information Protocol (RIP) and Service Advertisement Protocol (SAP) are supported by Linux IPX support. SAP is supported as part of Caldera's NetWare for Linux. Not only are these protocols necessary for client and server support, they're also important for Linux to act as a router or bridge. In these cases, Linux doesn't have to provide file and print services.
A Linux NetWare server can support multiple network adapters. The IPX routing daemon works with two or more network adapters allowing a Linux server to tie multiple subnetworks together so workstations on one subnetwork can access servers on another.
Linux IPX support works with 802.2, 802.3, and Ethernet II protocols. Client and server operation also make use of the NetWare Core Protocol (NCP), which is how file and print services are managed. Linux IPX and NCP support works over remote Point-to-Point Protocol (PPP) connections in addition to network connections.
Directory services
Linux supports both NetWare 3.x and NetWare 4.x/5.x networks. The former
utilizes the NetWare bindery and the latter uses NDS. The bindery protocol
supports servers as individual entities, while NDS collects all servers, and
other network objects, into a common directory tree. NDS is preferable
because it easily manages multiple servers. NDS can also coexist with
bindery support. In fact, adding the line
set Bindery Context = ORG1.DOM;ORG2.DOM
at a NetWare 4.x/5.x system console allows a specific NDS context to be specified for bindery emulation.
Standard Linux NetWare support addresses the NetWare bindery, which allows operation within any NetWare network. There are some limitations, however, even when this support is used within a network that supports NDS.
First, a client must log into each NetWare server individually prior to accessing file or print services. Under NDS, a single login provides access to any server in the network where the user has the proper access rights. Second, individual user accounts with matching passwords are found on each bindery-based server. This is of little consequence for single-server environments, but user and password synchronization has become an issue in multiple-server environments. NDS also overcomes this problem.
Caldera NetWare for Linux (click for full size image 38K) |
Caldera's OpenLinux comes with client NDS support. OpenLinux works equally well in a bindery environment. Client support allows a Linux PC to access NetWare file and print services, but doesn't allow the PC to provide these services.
Caldera's NetWare for Linux brings NDS server support to Linux. It can be applied to Caldera's OpenLinux or most any other Intel-based Linux implementation, such as Red Hat Linux.
NDS is important for a number of reasons. Not only does it include all network objects, such as users, file servers, and directories, into a hierarchical tree, it also manages an object's ACL (access control list). For example, an administrator can provide access to a particular directory by including a user or group in the directory object's ACL. This means the administrator doesn't have to worry about where a user logs in or the location of the directory.
Linux as a NetWare client
Operating Linux as a NetWare client isn't difficult, especially if you
use Caldera's OpenLinux. You can get a NetWare for Linux client complete
with NetWare NCP bindery support from the Caldera Web site (see Resources. It provides access to the file and print services located on any NetWare file server, although NetWare 4.x/5.x must have bindery support enabled.
Most Linux users will be comfortable with the NetWare client operation. NetWare configuration consists of two steps, which are similar to those required when setting up Windows Samba support or NFS support under Linux. The first step is to set up the IPX protocol. The ipx_configure program handles most of the protocol configuration. This step includes selecting the underlying protocol, such as Ethernet's 802.2. The second step is to mount the appropriate NetWare volumes. The ncpmount program handles these details.
As with most directory-mounting support, NetWare volumes can be mounted when Linux starts, when a user logs in, or when initiated by a user. The same is true of printer support.
OpenLinux brings NDS support to the table. NetWare client installation is included as part of the LISA (Linux Installation and System Administration) tool's setup as a check-box item during network installation. Some of the configuration and administration program names differ from the free version of the NetWare support. NDS support is included by default, although an OpenLinux client works equally well on a network that only has NetWare 3.x file and print servers.
Linux as a NetWare server
Using Linux as a NetWare server requires a little more effort. However, there are
major differences between capabilities and management of a NetWare server
and a Linux server.
The Linux NetWare server comes in three flavors:
Network administrators have a significant incentive to use Caldera's product. The NDS support allows a Linux server to be incorporated into larger (i.e., dozens of servers) NetWare environments than bindery installations. And this advantage holds even if a Linux server is added to a network with a single NetWare 4.x/5.x server, since both servers can be managed from a single workstation.
Both bindery and NDS versions provide file and print services. However, neither version supports NetWare loadable modules, which are used for operating system extensions and third-party support. The NetWare Web server is a NLM, and file backup is provided by a number of NLMs. Linux has comparable services for some NLM-based services such as the Apache Web Server, but most of these services won't be available across the IPX link used by the server. Instead, most of these services are made available over IP. Clients can make use of these services if the client supports multiple protocols.
Some useful NLMs are replicated as Linux applications. For example, nwmonitor provides some of the basic functionality of the Monitor NLM. Unfortunately for NetWare administrators, there is no direct correspondence to management of NLM names and Linux application names. Likewise, configuration files are unique to Linux and have no real counterpart on a NetWare server. On the other hand, a Linux user will have no trouble using the tools provided by Caldera.
Where does a Linux NetWare server fit?
While using Linux as a NetWare client has obvious advantages, the usefulness
of Linux as a NetWare server isn't always clear. NetWare 4.x/5.x are much
better platforms than Linux for plain file and print services. NetWare's
strong third-party market makes it suitable as a database server or backup
server. Still, there are a number of circumstances under which Linux as a NetWare
server is ideal:
Linux can also be a low-cost NetWare server alternative if NetWare 3.x compatibility is sufficient. While Novell is continually trying to move NetWare sites to NetWare 4.x and now NetWare 5.0, there are still a significant number of sites that remain on NetWare 3.x. Linux can provide additional file and print services in these established environments, without the added per user costs incurred using Caldera's NetWare for Linux with NetWare 4.x compatibility and NDS support.
The primary issues in adding Linux to an existing NetWare site are support
and management. Managing NetWare is significantly different from managing
Linux. While Linux has many advantages, there are still NetWare
administrators who will avoid adding Linux at any price. On the other
hand, those that embrace new technology will find more than just NetWare
emulation.
Discuss this article in the LinuxWorld forums
(0
postings)
(Read our forums FAQ to learn more.)
About the author
William Wong is a consultant and freelance writer.
|
Advertisement: Support LinuxWorld, click here! |
