Linux and Samba in 75 Minutes Everything you need to know (almost)

1. Linux and Samba in 75 MinutesEverything you need to know (almost) Presented by Mark Minasi author, Linux for Windows Administrators www.minasi.com / help@minasi.com

2. What this talk is all about As an Windows networking professional, I’ve spent the past ten years doing most of my networking work with Microsoft OSes. But I heard more and more about the Linux phenomenon and by 1999 I was intrigued to learn more about it. But I didn’t want to have to wade through the large books on the shelf that assumed that I knew nothing about networking. I wanted a short overview of what Linux was and what it was good for, how it compared to NT and how it could work with NT – and that didn’t stop to re-explain to me what a file share was. Well, that book didn’t exist, so I set out to find out more about Linux and write that book. Here’s what I learned.

3. Overview • Why would (or should) a Windows support professional care about Linux? • How the Linux world works • What do people use Linux for as server? • What can Linux do on the desktop? • Linux and Windows together • Linux versus Windows!

4. Why Care About Linux? • Linux can complement or replace some Microsoft OS functions • Linux is the #2 OS and growing • Linux licenses are free, can save money • You’ll probably eventually have to deal with interoperability • Demand for Linux admins is growing • Linux business model is worth understanding

5. How the Linux World Works

6. The Linux Worldwhy it’s “linnix,” not “line-ix” • In the late 80’s a writer built a free micro-Unix for teaching called Minix (“minn-icks”) • Linus Torvalds decided to build a Minix • But realized he wanted to do more • So he re-named it “Linux” • Original Linux very basic, no networking even • Released 5 October 1991

7. The Linux World it’s free, but it’s not public domain • Torvalds released the OS, source code and all, to the general world, using the GNU Public License • GPL says: • Use Linux and its source in your own products • You can even charge for your product • But you must, in turn, offer your source code • And you cannot restrict others in the use of your source • It’s called “open source”

8. The Linux WorldBenefits of a GNU approach • To paraphrase Linus, “no bug is hard to find when many eyeballs are looking for it” • Customers can fix the bugs themselves • Customers could even prove/disprove the validity of a vendor’s claims (“UTSL”) • “White box” support • This isn’t a new idea (MVS, VMS, Unix…)

9. The Linux Worldare they the only guys? • No, just the ones with a critical mass and no AT&T interference • A similar project, the “FreeBSD” folks, turned out another excellent Unix clone • But an AT&T lawsuit scared many away and lost them time • But it’s still around in Mac OS

10. The Linux Worldwhy would a vendor do this? • Open source recruits the customers to help find and fix bugs • Then the firm sells support, consulting, certification, training, and other items • You need not be open source to write Linux applications

11. The Linux Worldthe main point about open source Open source is the single most compelling thing about Linux. Period. If Linux were to accomplish nothing more than forcing others to open their source, then it would be perhaps the most significant event in this industry in decades.

12. The Linux Worldso how do you make money doing this? • Good question • In fact many Linux companies are asking that question • One approach: support for pay (RH, SuSE) • Another one: use Linux to sell hardware • Novell thinks they’ll make money putting NetWare atop Linux

13. Linux as a Server

14. Mail Server, with Exchange or perhaps Notes Web Server, with IIS Directory service (AD or NT 4 domains) File Server Print Server Database, with Oracle or SQL Server Name server (WINS or DNS) IP infrastructure (DHCP) What Do We Use NT For? There are other uses (routers, firewall, dial-in, mainframe gateway, etc) but they’re not major uses

15. Web server Mail server DNS server File server Print server Firewall Router Database server (relatively new but amazingly fast-growing) Appliance platform What People Use Linux For (server-wise)

16. What People Don’t Use Linux For • Nowadays… • Almost nothing • There is even work on Linux tools using proprietary Microsoft protocols like MAPI

17. Linux as a Web Server: Apache • Created as a joint effort by many; result was “a patchy server” • Good for hosting multiple sites • Robust • Good CGI, programming platform • Cannot host Active Server Pages off-the-shelf but Halcyon and Chilisoft as well as PHP are replacements albeit without VB support • Most popular Web server program on the Net

18. Linux as a Mail Serversendmail, postfix, qmail • Basic, well-understood Unix mail program • Supports SMTP • Does not support MAPI • Nightmarish to configure • Fast and robust • Used by countless Unix mail servers • Simpler options: postfix and qmail – but still no picnic

19. Linux as a mail servergetting the mail to the user • POP3 and IMAP4 tools ship standard • Web-based mail available through SquirrelMail (also free) • There are a couple of Outlookalikes; most significant is probably Ximian Evolution

20. Linux as a DNS Server: BIND • Again, the standard program in its category • Bind is very light on the CPU usage, so you can put up an enterprise-strength DNS server on a Pentium 100 with 32 MB of RAM • Edit a set of ASCII files called “zone files” to modify the DNS database, or Linuxconf helps • Works flawlessly as a dynamic DNS server for AD

21. Linux as a Firewallipchains and iptables • ipchains/iptables commands (Kernel 2.2/2.4) • Can do NAT (“IP masquerading”) so it could share a DSL connection throughout the house • Like Internet Connection Sharing • A bit obtuse setup-wise but just three lines will set it up • Can implement basic security • Can support dial-in

22. Linux as a File/Print ServerIn Windows networks • Free tool called “Samba” • But more on that in a minute…

23. Linux as a File/Print ServerIn Unix networks • Most Unix boxes share volumes using the Network File System, NFS • Linux can be either a client or server for NFS • Windows boxes would need an NFS client • Printing: • lpr (client) and lpd (server) included (“tcp/ip printing”) • NT family has client software to talk to lpd servers

24. Linux on the Desktop Can it offer Windows with less pane?

25. Linux and GUIs • GUI exists but is (mostly) optional • Several GUIs available; simplified: • KDE more common • GNOME competes, newer, from the GNU folks • You shouldn’t have to put a GUI on but some Linuxes misguidedly mandate it • In general a Linux GUI app that works on KDE works on GNOME and vice versa

26. Do I have to use a GUI?windows icons mice & pull-down menus = WIMP interface • No, Linux has a long tradition of command line tools, very powerful ones • Called a “shell” program • Linux uses “bash,” the Bourne Again SHell • Great power lies in its script-ability • Once more powerful than Windows scripting but MSH and WSH change that

27. Are there apps for Linux?now that I’ve got the GUI up… • The good news: several application suites • Star Office • OpenOffice • Some great free ones, including a Pilot organizer • The bad news: they’re just not as good as the Windows offerings, lack the “fit and finish,” and the integration • Worse, most are spottily improved – no “corporate presence” to keep things going for years

28. Making It Work What will I need to run it?

29. Making it WorkWhere do I get Linux? • Many, many Linux “distros” • Two big players: • RedHat: $180-2500/year/system • SuSE: $110/desktop, $800/server, $1250 for “open exchange” server w/10 CALs • Many more at www.linux.org/dist/list.html

30. Making it WorkWill Linux Work On My Hardware? • Maybe; drivers are written by volunteers • Really new stuff and expensive stuff may lack drivers • Video configuration can be a nightmare although it’s gotten better • PCMCIA NIC configuration fails on many systems • Laptops offer more challenges than desktops • Printer drivers can be hard to find

31. Making it WorkHmmm, then what about support? • Who’s going to support a free operating system? • The idea is that you give away the software and charge for support • Again, all support people have source code access in the Linux world, not just a few • Linux firms offer answer-all-questions annual fees that can be reasonable • But it’s not like they’re going to write drivers for you • And if you want a chuckle, pull down the HCL

32. What about free support? • There are a lot of “howto” documents at ldp.org, the Linux Documentation Project • Google Groups has often answered questions for me • What about asking questions on Linux newsgroups? • My advice: assume a female screen name and claim to be 22 years old

33. Interoperating with Microsoft

34. InteropCan Linux Co-exist With MS OSes? • It can read and write FAT and FAT32 • Can read NTFS, writing’s dicey • Most need a special “EXT3” partition and a “Linux swap” partition • Strongly recommend Partition Magic! • Can dual-boot using LILO or GRUB • Flexible and powerful but not always implemented well

35. Interopcan I run Microsoft apps on it? • An old tool called dosemu will run many DOS apps • For Windows apps, the news isn’t as good • A tool called WINE looked pretty good in 1999 • But in the middle of a revamping it sort of faded away • There are RDP clients for Linux; one answer • Or there’s VMWare

36. Interopwhat about Samba? • Very significant tool that just keeps getting better • Started out as a project to support interop with Digital PathWorks • Basic goal is to implement file server and client tools using the Server Message Block (SMB) protocols and now CIF

37. Sambaclient-side • Linux boxes can do the equivalent of a NET USE to a Windows server • Tools: smbmount and smbclient • SMB signing may be an issue but honestly even Microsoft is having trouble with it and Samba 3.0 seems to have it licked

38. Sambawhat the server can do • Make a Linux box act as a • Workgroup server • NT 4 or AD domain member server • WINS server • NT 4 PDC • Support LM, NTLM, NTLMv2, Kerberos • Usually significantly faster than Windows at file sharing

39. Sambaconfiguring it • Controlled with a text configuration file /etc/samba/smb.conf • Or use a Web-based configuration tool called swat (“Samba Web administration tool”)

40. Sambathe hard part… integrating accounts • Once a Samba box is part of a domain then we can do the usual permissions and authentications • Relatively new tool Winbind makes this much simpler • Once installed, any domain member can sit down at a Linux box and log in using domain credentials, with no corresponding local account on the Linux box

41. Bottom Line:Windows vs Linux let’s see, I put that asbestos suit somewhere…

42. Linux Pros • Faster SMB file server than NT • Basic Internet infrastructure (Web, mail, DNS, firewall, router) tools excellent • Inexpensive, the perfect second DNS server • Open source model may offer better quality overall • Uptime: you can often change a driver without rebooting

43. More Linux Pros • Most tools that come out for various Unixes will run on Linux • Although there are many versions, they’re all compatible • It’s possible to refine a copy of Linux to do just one thing, and do it amazingly quickly – rip out the stuff you don’t need, crank the buffer sizes, and get knock-your-socks-off performance • Per-system license costs may be very low

44. Linux Cons • A real challenge to set up • Drivers and apps are scarcer • Often can’t support MS standards like MAPI or Active Server Pages • Not as good at multiprocessor as NT • Retraining – ever recompiled a kernel? • Less flexible permissions structure

45. More Linux Cons • GUI is less polished than Windows • I believe that the Linux developer community is, in general, not committed to the kind of hand-holding that Windows does as a matter of course

46. Recommendationsfirst steps • Get it and start playing with it! • Get several distributions, although I recommend SuSE at the moment • Consider setting up a Samba server as a domain member, or perhaps a DNS, Web or mail server

47. Thanks! • I hope you enjoyed this talk • Questions? • I’m at help@minasi.com • I invite you to sign up for my free e-newsletter at www.minasi.com • Please consider buying The NT Expert’s Guide to Linux when it’s finished • www.minasi.com/linux for PPT

48. Linux and Security

49. Linux and Security • One point where Linux and Unix differ • Uses permissions & user accounts, as in NT • But you don’t make users admins; rather, they all just share the “root” password • You can only set permissions for one user account and one group • Then you set “world” permissions for anyone who’s not that user or in that group

50. Interop Areas • Coexistence • Bind, Apache, Sendmail, ftp • Mimicry • Samba, LPR/LPD, RDP clients for Linux • Directory Sync • Some products, none shipping yet • Emulation • dosemu, wine