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ARTICLE SOURCE: http://www.zdnet.com/pcmag/pctech/content/18/11/tf1811.001.html Linux 2.2 Gives NT a Run for Its Money--for FreeLinux 2.2 rivals Windows NT 4, boasting a comprehensive complement of features, capabilities, and compatibilities--even running on x86-based machines. What's more, it's free. Linux and Apache remain an attractive choice for web servers compared with Windows NT.By Neil Randall Microsoft is worried. The last time the company was in this predicament, Netscape had just started up and Bill Gates suddenly discovered the Internet. But it's one thing to fight off a single company and quite another to stop a worldwide revolution. That revolution is Linux, the POSIX-compliant Unix operating system, now out in Version 2.2--a significant new update. For the cost of a download, you get a feature-rich version of Unix that runs on platforms ranging from 386s to SPARCstations, gives you superb Internet tools, including the extremely popular Apache Web server, and runs an increasing collection of applications and utilities, many available free from such download sites as Linuxberg (www.linuxburg.net) and Freshmeat (www.freshmeat.net). Several computer makers, including big names Dell and IBM, are even offering desktop systems with Linux preinstalled, either alone or as a dual boot with Windows 98 or NT. And Linux keeps getting better with each release. With Linux 2.x, not only is this open-source operating system gaining support from third-party developers (including heavies such as Corel and IBM), it also now approaches and in some cases even surpasses Microsoft's high-end OS, Windows NT 4.0, in areas such as scalability and support for 64-bit processing and multiprocessing. You also need far less hardware to run Linux than Win NT; a good old Pentium/166 is just fine, and you can even press that 386 doorstop into service. Furthermore, Linux is much less likely than Win NT to need rebooting after running for weeks and even months. Windows NT is widely acknowledged as having a more user-friendly interface, but Linux users like the control they have over their OS. Unix remains the dominant operating system for Internet servers. Linux makes Unix even more central to the Net, because it runs on PCs and thus could vastly increase Unix's presence. Moreover, Apache--the most widely used Web server software--runs best on Unix. (The latest version of Apache runs on Win32, but not as fast as on Unix.) Combining a Linux-based PC with Apache server software results in a powerful, low-cost Web server, which you'll see used increasingly on both low- and high-traffic sites. (For a PC Magazine Labs-tested comparison of Web server platforms, see the "Serve It" section of this issue's feature "Create a Great Site.") You can expect to see more Linux Web servers and Web clients as well. So let's dig in. We'll start with a look at the major enhancements to the new kernel (that is, the core OS components). Then we'll examine the Internet and networking features in 2.2, along with a related discussion of file system changes and additions. A brief comparison with Windows NT runs throughout the sections, to show you how the two systems stack up. ----- The 2.2 kernel offers a number of improvements over earlier versions. First and foremost, its cross-platform support is far more extensive. The new kernel will run on x86 machines with 386 or higher processors, the Apple PowerPC line, SGI Virtual Workstations, Alpha and SPARC systems, and even Amigas and older (68K) Macs. Windows NT, by comparison, runs on 486 or higher systems, Alpha stations, and SGI Virtual Workstations. In the case of Alpha and SPARC, the Linux 2.2 kernel supports 64 bits, so if Intel ever releases the 64-bit Merced, Linux will be ready with a native 64-bit kernel. It's unlikely that Windows NT will offer 64-bit support until significantly after Merced's introduction. If Intel does a good job selling IT departments on the benefits of 64-bit processing, those departments might well consider 64-bit Linux as a possible enterprise server OS and adopt it before 64-bit Win NT is ready. If that does happen, Win NT will have a hard time displacing these high-powered Linux systems. Many of these platforms--Intel (PII and higher), Alpha, SPARC, and SGI--support multiple CPUs, and 2.2 offers improved support for symmetric multiprocessor architectures. Though the same 16-processor limit supported in the 2.0 kernel still holds, 2.2 enhances the feature dramatically. The earlier version prevented two or more processors from accessing the kernel's services simultaneously, by locking the kernel as soon as one processor requested a service (global lock). By contrast, 2.2 supports multiple locks (they're called spin locks), and this feature allows multiprocessor access to the kernel as long as no two CPUs request precisely the same service. The result is a faster multiprocessing system with less idle time, and this speed pays off with, for example, large-scale Web servers handling simultaneous requests from many users. Win NT allows up to 32-way symmetric multiprocessing but works best with a maximum of four processors. Another benefit for large-scale servers is the new kernel's improved support for RAID (Redundant Array of Inexpensive Disks), which lets hard disks mirror one another on the fly so that disk failures won't result in the loss of either data or system functionality. (RAID can also be used to store one set of data across several hard disks in one write operation.) This support isn't perfect, though: Linux 2.2 won't automatically recognize all the disk arrays at boot time (administrators must set them, but this can be scripted), and you can't replace defective drives when the system is running (hot swapping isn't supported). You can, however, expect an upgraded RAID driver in a near-future kernel upgrade to offer these enhancements as well. Version 2.2's RAID support brings Linux closer to parity with Win NT 4.0, which already offers a rich RAID environment, including support for the boot-time and hot-swapping features that Linux lacks. Kernel 2.2 has good news for all Linux users, not just network administrators, in its support for additional hardware. The kernel now supports infrared (IrDA) ports, ISDN modems, and more SCSI controllers than it did previously. TV tuner cards and video capture cards are enhanced through a new driver (BTTV), which, among other things, lets the card write directly to memory, bypassing the CPU, to produce a higher-quality image. Sound cards are also more widely supported, as are more of those essential business tools, joysticks and game controllers. Plug-and-play support remains limited to parallel ports (although you can find some PnP drivers on the Net at such download sites as www.linuxberg.com), but Linux now supports a wide range of IDE devices beyond hard disks. Ultra-DMA data transfers are also built in, along with bus-master DMA. Linux 2.2 also helps solve one of Linux's most frustrating installation problems--an unrecognized video card--by introducing direct graphics support. Here, a frame-buffer console driver lets your system's X Window server treat the video buffer as a separate device and remain independent of the card. Recompile No More The 2.2 kernel also helps reduce the need to perform a task that frightened many users trying to switch from Windows or Mac machines to Linux: recompiling the kernel. Until Version 2.2, configuring the kernel meant that you had to rebuild and recompile the existing one. Linux 2.2 still lets you rebuild and recompile the kernel to your heart's content (otherwise Linux devotees would launch a global revolution), but you can now change the kernel's configuration through Linux's virtual file system instead of rebuilding and recompiling. It's still not point-and-click, but 2.2 includes full documentation for kernel configuration, and as this feature gains popularity, you can expect the interface to get friendlier. ----- The whole point of Unix has always been networking, including the incorporation of non-Unix systems into Unix-based networks. Linux is no different from other Unix platforms in this respect, and in fact, it was never really designed as a standalone workstation OS, as was DOS or early Windows. These networking capabilities are essential to establishing Internet servers. Linux has long been recognized for its ability to let you establish inexpensive servers, and the 2.2 kernel will only increase that recognition. Network operating systems often have to contend with multiple file systems, and Linux has been as good or better than any in file system compatibility. For example, Windows NT can read and write only FAT, FAT32 (Windows 2000 only), SMB, and Win NT's native NTFS (which will change in Win 2000). Linux supports far more. In addition to its two native file systems, EXT and EXT2, and its virtual PROC file system, Linux shares Windows NT's ability to read and write FAT and FAT32, though it can only read from (not write to) NTFS. Beyond Win NT's file systems, Linux supports UMSDOS, which lets Linux run from a DOS partition instead of a Linux native partition; SMB, for Windows for Workgroups and LAN Manager compatibility; and NCPFS, for compatibility with NetWare clients and servers. Furthermore, Linux is compatible with Unix's NFS, UFS (BSD and Solaris), SYSV (Xenix and SCO), and the Amiga Fast File System (AFFS), along with Carnegie Mellon's advanced distributed file system, CODA. Such wide file system support, combined with Linux's platform support, allows it to be installed and used on a wide variety of systems. Windows NT, by comparison, can be installed as a dual boot on fewer systems and with much less file access. ----- Important for intranets, Linux now supports IP tunneling, which lets you configure a machine to belong to a network different from the one to which it is physically attached. Tunneling uses the Internet Protocol (IP) to transport data that's encapsulated according to the needs of other network protocols. Windows NT's tunneling comes in the form of Virtual Private Networking (VPN), which lets you use an IP connection to transport network data from non-IP network protocols such as IPX and NetBEUI. Linux's new IP Tunneling feature handles only IP within IP, and is therefore less flexible than Win NT's, but the important point is that the feature exists at all. The Linux community will no doubt add other tunneling drivers to let IP transport data from other protocols, such as the ones Linux already supports (IPX, AppleTalk, SMB, and LLC). The Linux 2.2 kernel supports TCP/IP Version 6 (IPv6), the forthcoming upgrade to existing IPv4. IPv6 expands IPv4 by supporting such features as expanded addressing, new and future authentication and privacy implementations, simplified header formats, increased support for mobile users, and ease of configuration (see www.ipv6.org for more details). Neither Win NT 4 nor Win 2000 offers built-in IPv6 support, although Microsoft provides information about its upcoming IPv6 implementation for both systems on the Web (www.research.microsoft.com/msripv6). That Linux's support is in place lets developers start implementing IPv6 versions of their products and programs for Linux early, which will be a draw for administrators of advanced networks. Support for two other IP protocols has also been added to the 2.x kernel. First, IP multicast routing is now included with the kernel. This feature enables a system to send the same packets at the same time to more than one computer on the network--the standard Internet way is to send copies to every addressee--and thus to engage in Mbone videoconferencing and other live over-the-Net events, not just as a client but as a server as well. Neither Win NT 4 nor Win 2000 supports IP multicast routing; thus they can't act as servers, although they do let programs such as Microsoft NetMeeting act as multicast clients. Since IPv6 actually enhances Mbone capabilities, Linux's support gives it another potential advantage. Another feature, IP Masquerading, lets your entire network appear to the Internet as a single IP address, as though the network were operating through a firewall; Win 2000's Network Address Translator performs a similar function. For dial-in connections, 2.2 offers serial-line load balancing, letting you connect to an ISP through two phone lines and two modems to double the connection speed. As with Windows' multilink feature, the ISP must be set up to allow such connections. Configuring the network interface in Linux 2.2 now automatically establishes routes for existing local networks: You no longer need to add them manually. In fact, the 2.2 kernel offers far greater flexibility for customizing routing decisions, letting administrators, for example, schedule packets for specific behaviors according to specific traffic-congestion problems. And data can be routed according to a range of criteria, such as the originating IP address. These capabilities, along with a new rules-configuration manager for firewalls, enhance both the power and the ease of implementing networks in Linux. ----- No, Linux is not perfect. With the 2.x series of kernels, Linux continues to evolve, and because of the specific features in its evolution, combined with the installation enhancements offered by the major distributors of the OS, it will continue to cut into Microsoft's still vastly superior share of desktop and (especially) server installations. But apart from the fact that organizations and individual users alike still feel nervous about working with an operating system that comes from--and is supported by--no central source, the fact remains that Linux 2.2 still lacks features that have become crucial to many users. Crucial, at least, if massive adoption of the OS is the goal. First, support for plug-and-play is still poor. Of course, you could say the same about Microsoft's PnP, but try installing even a commercial distribution of Linux (from Caldera or Red Hat, for instance) and Windows 98 on the same machine and Win 98 will automatically detect and configure far more devices. If you're coming to Linux from the Mac, which has always had superb plug-and-play support (so good, in fact, it didn't even have to be called PnP), you'll find this even more frustrating. Getting the video system to work with X Window is better than before but still too difficult for many--indeed possibly most users--as are the disk-partitioning requirements at installation. Another problem that remains in the new kernel is the dearth of drivers for PCMCIA cards. If you're connecting your notebook to your LAN via a PCMCIA network card, and to the Internet from the LAN, you'll have to find drivers from your manufacturer (not all offer Linux drivers) and install and configure them yourself. In addition, kernel 2.2 doesn't support the Universal Serial Bus, although experimental versions are available. This isn't a huge problem yet, but as more USB peripherals appear, the lack of support could render some systems unusable. This is obvious with such fundamental USB devices as keyboards and mice, but it will also be true as USB modems make their appearance, and that will affect Internet functionality. So will the slow arrival of support for cable modems and DSL modems, but that's also the case with cable and DSL services themselves. Still, as such services become widely available, Linux users will want immediate support; Linux seems made, in fact, precisely for such high-speed connectivity. There's no doubt, however, that Linux will continue to grow as an Internet server platform, and--to a lesser degree--as an Internet client. The 2.x family of kernels ensures an increased acceptance. All of this means, of course, that the Linux/Win NT debate will continue to thrive, especially given the fact that new Linux kernel versions will continue to appear, with a growing number of features and compatibilities, as network administrators await the long-delayed Windows 2000. No wonder Microsoft is nervous. ----- Linux 2.x Windows NT 4
----- Caldera OpenLinux With graphical KDE desktop environment Debian/GNU Linux Includes more than 1500 packages - all free Linux Mandrake Includes Apache Web server and more RedHat Linux Everything you need in one package Stampede GNU/Linux One of the fastest distributions ever S.u.S.E. Linux More than 800 software titles included ----- Recommmended Resources • Slashdot.org Linux community • Freshmeat Linux downloads • LinuxHQ Kernel news • Themes Linux software • Google Linux search Check out ZDNet's Linux Channel for a complete resource guide. Also on PC Magazine • Create a Better Web Site: Serve Your Site -- PC Labs Reviews Which OS is best for your Web server? Elsewhere on ZDNet • Linux Channel -- ZDNet • Linux Discussion -- Community Center • Linux News -- ZDNN • HOWTOs and FAQs -- Help Channel • Linux Knowledgebase -- Help Channel |