UNIX for Dummies Questions & Answers

I am new to UNIX (about a year) and learning as fast as I can. I am an instructor teaching UNIX and have two labs with Ultra 10 333 MHz, Sun Blade 1000 1 GHz, Blade 100, and Two Enterprise 250 Servers. We are currently teaching our classes using the Solaris 2.10 OS, downloaded in May 2006, I am not sure of the exact release. I have heard that version 10 is rarely used in production systems and that most businesses are using 2.8. If this is the case, should we be teaching students on the OS that they are most likely to be using when they are hired? I am familiar enough with Solaris 2.9 to see some of the differences between 2.9 and 2.10, but completely unfamiliar with Solaris 2.8.

We have 180+ UNIX boxes, >140 of them are Linux. We have a few Solaris 2.9 boxes.
What you should teach (aside from admin tools which differ a lot) is POSIX stuff as much as possible - POSIX C, scripting, etc. Wherever your platform deviates significantly from the norm you need to let students know what the norm (POSIX or XSI) is. And, the common shells on production boxes are Bourne, Bourne-again (bash), csh, ksh, then tcsh. (Steven's Advanced Unix Programming 2ed p 3).

However, consider teaching either Bourne or bash, not csh or tenex csh because those are so, um, "tricky", that platforms like FreeBSD and Darwin that have tcsh as their default shell, use Bourne for system scripts. Solaris comes default with all of the shells.

Thanks, we are teaching scripting, but need more; currently we lean towards the ksh, although most of the material that I have read does state that scripts should typically use the Bourne shell.

Hmm, most of the scripts I write use ksh but I admin mainly Solaris boxes. The fun part is trying to create scripts that work equally as well in multi platform environments.

As to which Solaris, the shop I'm in now is a mixture of Solaris 2.6 up to Solaris 10 in a few cases (about 250 or so Solaris boxes). We also run Suse and Red Hat, AIX and a few HP-UX systems. The last shop I was in (I'm a consultant) used exclusively Solaris 8 with various versions of Red Hat (ES and AS) and AIX.

I have three Sun boxes here at home with Solaris 8, 9 and 10. I'd say that if you teach 9, the info will work pretty closely with 8. There are some system level changes in 10 that tend to catch me from time to time and I have to go look things up. They're good changes but different enough from 9 and lower that I have to stop and think for a second. So if you teach 10, a shop with 8 might catch your students by surprise.

Carl

We have > 600 Solaris boxes and > 200 linux boxes on the site I work in.

We are running < 25% Solaris 8, ~ 40% Solaris 9 and the rest on Solaris 10. This is an R&D office but the Solaris 10 system will be released in Q1 of next year.

In stepping from Solaris 9 to 10, the changes are vastly greater than those in going from 8 to 9. Solaris 9 could in many ways be looked at as being a facelift version of Solaris 8 or even 7. So I'd have to agree with Carl, 8 or 9 amounts to the same really, but 10 is quite different in some areas.

The difinitive advantage of ksh is that 'ksh is intended to conform to the Shell Language Standard developed by the IEEE POSIX 1003.2 Shell and Utilities Language Committee', so it may be considered as standard shell for UNIX boxes.

See also http://cbbrowne.com/info/unixshells.html

You will find that ksh is available on almost all boxes, but not on Linux. I haven't seen any Linux based system that had the original ksh. There is a pdksh, but it differs from the original ksh and you may find that your scripts fail in unexpected places.

If you want to write scripts that will work on any system that they are run on (and that in itself is pretty difficult), you should use sh.