random linux thread

Kicking this off as a continuing thread.. I generally don't document my adventures with linux well, so thinking that as I emerge from each successive, uh, system improvement, I might find it entertaining to put my learnings on the net. One of my clown buds calls this "the librarian gene", I think. If not, then he calls something else the librarian gene. uh, and besides, all too often I re-encounter the problem multiple times but can't quite remember how I dealt with it. ugh. :-(

1) vmware 6 on a core 2 duo machine is seriously fast. And useful. (Be sure to clean out old config files though.. they can cause all sorts of bizarre behavior.)

I've kept two machines around just about everywhere I sit: one for linux, the other for windoze, with the file store on linux. Samba on linux serves available directories to Windoze.

I'd be tempted to go to OS X, since Mrs. Clown and the three Little Clowns use OS X, and I am de facto sysadm for Chez Clown, but I've become addicted to 1920x1200 LCDs which are more commonly and cheaply available on laptops designed for Windoze. (In fact, the last time I looked, I didn't see any Apple 1920x1200 laptops, but that was months and months ago.)

However with wxp running so fast in vmware, I'm kinda thinking that the windoze box is functionally surplus. Why have two machines when one will do as well? Especially since the One Great Machine is a laptop that runs faster than my 3yo technology desktops..

I have the impression that xen might be an even better choice, but there's a learning curve, and I ask you: WTF do clowns need virtualization for?

The only downside I see at this point is vmware's recommendation that I suspend the VM before I suspend the laptop. I think I've absent-mindedly suspended the host OS (er, that's Linux) without suspending the VM, but I'm not sure that I want to play bleeding edge games.

uh, why would one need two machines? (whether they're two physical machines or one physical and one virtual machine..)

well, what are the choices?

a) Windoze only? oop ack gag. Sorry, it's a religious thing..

b) Linux only? Much as I hate to admit it, there are some things that linux just doesn't do as well as windoze. (Yeah, I know: heresy!) Playing media files out of firefox is one example, but really: Office is the critical application in corporate America. Unfortunately, OpenOffice isn't sufficiently compatible with M$ Office that I can use OpenOffice for file interchange with my colleagues.

In fact, after the update of Office 2003 to SP3, OpenOffice coredumps when I open files written with Office. Damn!

2) Firefox has some serious issues on x86_64 linux. I'm not sure that Firefox is the culprit, actually; the problem might be the 64b wrapper for the 32b flash plugin. But even if I move the plugin out of the way, or replace the flash plugin with the gnash plugin, I still have problems.. pages take forever to load. But the problem doesn't show up immediately, and so far I haven't been able to pin it down. Typically but not always the tops process monitor shows firefox using 100% of the CPU, and so it goes until I kill firefox.

But wxp in vmware is running so well that I've been playing with safari-in-windoze as my main browser. Why safari? Mostly IE's checkered history.. but also ecological diversity. If all you're running under wxp is M$ software, you have a monoculture perfectly suited for a plague.

This isn't a novel observation, of course.

A pity that there's no safari for linux. I don't like the firefox interface, but I don't much care for konqueror either.

3) Saw an oops from the kernel last night, so I'm keeping a tail -f on the syslog running in a terminal window.. the symptom was that - in Windoze! - safari took forever to load, but wasn't showing up as pulling down CPU cycles in top. Not sure what that's about, haven't spent any time looking yet.

4) As implied, I move the laptop from network to network. (Cool iptables trick that may or may not be widely known, will mention down the road.) As said, I use Samba for internetworking between the linux file server and the Windoze VM.

I was way troubled for a while because my iptables firewall script kept kicking out bizarre references at 15 minute intervals.. to the DNS servers for the previous network!

This suggested that a virus or worm had installed a trojan working through port 53. Not a Good Thing for almost any definition of "Good Thing".

I'm not much of a network guru (what, you expected me to be entertaining and a network guru too??), so I didn't fire up snort, I didn't fire up tcpdump, I didn't fire up wireshark.. I did a bunch of ultimately futile other things.

But more or less by accident I noticed that when samba wasn't running, I didn't see stale DNS references. So I played with this a bit, and while I can't prove it, it seems plausible that smb or nmb is caching the DNS.

Eventually I should verify this with one of the network monitor tools, but unfortunately that aint happening right away.

4) I see a samba error in the kernel logs that people have been seeing just about forever: "Can't connect to" blah blah blah. (Yeah, that's pretty indefinite. I'll update with the specific error message later.) Unfortunately it appears that this can be the consequence of a gazillion different misconfigurations, so I suspect I will have to sit down and work through the samba manual with attention to detail.

On the other hand, it's not clear that it's costing much in performance, so I can and will let it go for a while, having already wasted at least a day poking around the web and finding nothing useful.

All in all, not the greatest advert for linux. It's not that there's anything wrong with the tools, it's that it's getting to be the case that you need so much recent background knowledge that even people whose experience goes back to the Dark Ages find themselves scratching their heads. And it can be hopeless for newbies who need some not-quite-standard configuration.

5) I've been kinda wondering about maybe running OpenBSD rather than Linux.. OpenBSD claims to be "designed for security", and the BSD family has a reputation for a network stack that's way superior to the Linux network stack. But again, it's a question of cycles and learning curve.