The Techno Bushwhacker

Screen Sharing from Ubuntu to OSX

2010-11-17T09:47:00.008-05:00

OXS has a great feature where all the local (and remote macs if you use Back to My Mac) appear in the finder on the left side bar. If the Mac supports screen sharing, you can connect to it there, along with the normal file sharing options.

Well Mac screen sharing is just VNC will Bonjour. Ubuntu supports both VNC natively and Bonjour through Avahi.

So how do we get an Ubuntu system listed in OSX's sidebar and connect with screen sharing? Well its pretty easy, but not obvious.

1. As su edit the /etc/avahi/avahi-daemon.conf:

sudo vi/etc/avahi/avahi-daemon.conf

change the line:

#domain-name=local

to:

domain-name=local

OSX uses the domain local out of the box for mdns/bonjour/zeroconfig. Linux uses what ever domain you use when you set up your host. Changing the avahi-daemon file overides your domain, and puts you on the local domain with your Macs.

2. Enable VNC.

In Ubuntu goto System | Preferences | Remote Desktop

Check the box for "Allow other users to view your Desktop."

Uncheck (if you wish) "You must confirm each access to this machine."

Check "Require the user to enter this password."

Set the password.

Close the Window.

This is what it should look like:

3. Test!

On OSX open up a finder window. You should see under the shared heading on the lefthand side USERS's remote desktop on UBUNTUHOST, where USER is the name of your user account in ubuntu, and UBUNTUHOST is the name of your ubuntu system.

Here is what it looks like on my system:

Now hit the Share Screen button at the top right of Finder. You will get a log in prompt. Enter the password you used when you set up Remote Desktop in ubuntu:

You should then get a screen sharing window showing your ubuntu desktop:

4. Limitations.

Screen sharing on ubuntu is a tad different the OSX. In OSX the screen is shared by the OS before any user logs in, so you can connect to your OSX system and then log in as any user. OSX also uses User authentication for screen sharing. Your OSX username is your screen sharing username. The same is true for your password.

In ubuntu, the screen is shared by VNC after the user logs into the system. This means that a user must be logged into ubuntu before connecting with screen sharing. It also means that after you are connected the screen sharing, and you log out of your user account in ubuntu the screen sharing connection will be dropped. Also, authentication is handled by VNC, not ubuntu. There is no username, just the password you set in the Remote Desktop settings.h

Drobo Speed and the Mac Pro

2009-10-12T19:42:00.008-04:00

I got a Drobo a little while back. Its a pretty cool device. I have however been a bit disappointed with the speed.

Searching through the internet I read that the FW800 interface on the Mac Pro ain't that hot, and that getting a PCI-E interface would prove faster. Well after hooping in newegg.com and $40.00 later, I tested it out.

Here are the results:

As you can see there is a pretty big difference. For example, sequential read with 256K blocks was about 38MB/s with the PCI-E card while the motherboard FW800 interface was about 22MB/s.

This benchmarking was done with XBench on OSX 10.6.1 with the Drobo having 4 Seagate 1.5TB SATA 300 drives.

Now the Drobo is faster, but still not as fast as I'd expect. Given that, Its still a pretty cool device, and speed is my only complaint.

Home Network Load Balancing

2009-06-09T22:03:00.005-04:00

I'm been downloading some stuff with bit torrent via RSS feeds lately. With all the talk of throttling by ISPs, and to achieve domestic tranquility by having the MRS not bitch about slow internet at home, I've implemented load balancing with pfsense and my 2 broadband connections.

With bit torrent opening up an assload of independent connections to hosts all over the internet, you would figure its a prime candidate for load balancing. Well its not. I'm still trying to figure out why, but to achieve any sort of reasonable performance, I need to force it to a single interface with firewall rules.

Anyone with insight into why this is, please fill me in.

Netbook SSD Performance

2009-05-07T10:50:00.026-04:00

I have a Dell Mini9. It has a 4GB STEC SSD drive. As SSD's are extremely different then HDDs in the way they operate, I was interested in its general performance under certain conditions.

My biggest interest is the difference between the stock Ubuntu 8.04 Hardy Heron and the New Ubuntu 9.04 Jaunty Jackalope. One of the primary differences between the two is that Jaunty supports EXT4 while Hardy supports EXT3. The kernel for Hardy is 2.6.24-SS LPIA, the kernel for Jaunty is 2.6.28-11 i386.

Now I know this is not a scientific test, as there are a bunch of variables that I have not controlled for, I.E.; kernel, kernel architecture, fs, and so on. I did use the noatime option on both ext3 and ext4.

All tests were performed with iometer. They were performed on /dev/sda1 as I didn't want to write directly to /dev/sda directly, as this would blow away the underlying OS. I may do that in the future.

The first set of tests is read performance, both random and sequential. I did this with 2 different transaction sizes, 4KB and 2MB. As the SSD block size is 4KB this is the smallest effective transaction possible. The 2MB size I thought was big enough to give an idea of larger transactions.

Both IO/s and MB/s are ascertained. The IO/s tells us how quickly a transaction can be accomplished. If you have multiple processes accessing different data simultaneously, the more IO/s you have the better. The MB/s is obviously how much data through-put that transaction provides.

Here are the results:

As you can see, Jaunty and EXT4 excel at every test.

Below are the write tests. To do the write test, the drive was aged. If you dont know why aging a SSD drive is important check out this article by anandtech.

Again, Jaunty and EXT4 excels. You can also see that the write through-put is very low. .03 MB/s. This is a result of the aging of the SSD. I will look at a fresh SSD's write performance soon.

Nine Inch Nails Live

2008-09-10T14:44:00.002-04:00

So last week I got to see the NIN concert in Philly. This was the tour for both Year Zero and The Slip. There was no show in DC so I drove up. Any one who has seen NIN live knows that the shows are a big deal.. lots of lights and crazy effects and stuff.

This show by far was the best I've been too, and I've been more then I can count. The technology they used for the light presentation was mind blowing. It appeared to be a massive grid or RGB LEDS that was probably 30'x50' that would lower infront of behind the performers. When it was dark, it could be seen through. The grid was able to obviously show video, but was was even more amazing is that it appeared to have light detecting nodes though out. With that they did all sorts of crazy things:

They put the screen infront of the band, and put the band in the dark behind it. Then they would do 2 spots across the stage infront of the band, behind the screen. Video would be shown on the screen, but as band members moved into the light, the video would black out in that area and that band member could be seen through the screen.

The next thing was nuts.. They put up a very minimal grid of squares on the screen. The drummer then walked out with a tiny flashlight and lit up some of the squares... it turns out the screen was a giant drum machine. He programmed it through out the song with flash light.

They also did lots of light feedback and effects by projecting other lights on the screen with the music.

For an engineering geek like me, it was truly an amazing thing to watch. The thought and creative energy that went into that show was just off the chart. If you ever get a chance to see NIN live, or pick up a concert video, I would not balk at the chance.

Pictures via Kelly

Plan!t Now

2008-03-04T12:57:00.010-05:00

I'm volunteering for Plan!t Now. It is an organization dedicated to grass roots disaster response planning.
As made evident by hurricane Katrina, some disasters can overload Federal and State disaster planning. By planning at the personal and community level, the damage can be mitigated and return people to thier normal lives quicker.

Plan!tNow

944 no more

2008-01-09T23:42:00.003-05:00

So my mostly finished 944 was totaled last month by an asshole. Oddly enough, the asshole wasn't me.

Here is why he is an asshole.
1. The accident was on Rt 66 in VA. In the middle of a 4 mile back up, this asshole figures out how to get up to about 40MPH, with out regard for a car that is stopped in front of him.
2. The asshole couldn't manage to find his brakes during his experiment with momentum. Or perhaps he was texting, and didn't even know he about to hit a car in a traffic jam that had been stopped in front of him for over a minute.
3. Emergency break down lane? Thats only for emergencies.. and its only an emergency after an accident right? Isn't there a law about pulling into that lane? I must be better to hit some one instead.
4. Who needs a drivers license really? I know I'm 17, have no experience behind he wheel, its dark, its raining, there is an assload of traffic and I'm by myself with my learners permit, what could go wrong?

Soon to come, why we should burn all the insurance companies to the ground, but not after my claim is settled by the nice, but amazingly incompetent people at nationwide.

Before

2007-10-05T22:27:00.001-04:00

So here it is. My SCCA racer with a blown engine. Note the green; the cars original color. Note the red. It is the worst paint job I have ever seen.

Below is a close up of the inside of the engine, from the nice hole I made. 30 year old engine+Racing=Broken Engine

Back From The Dead

2007-10-01T02:41:00.001-04:00

IMG_3187.JPG
Originally uploaded by prioret

This weekend I started the process to bring my race car back from the dead.

Last year, the first weekend I had the car on the track I blew up the engine. I knew it was coming. The engine was about 29 years old, and not really worth rebuilding for racing. I was hoping to get a whole weekend out of it. I got half that.

Now, thanks to ebay, I have a new(er) engine. I sent it off to the builders to race prep it a few weeks ago. This weekend, I had the car brought to the shop.

This week I will pull the old engine out and get it ready for the new one.

Some info on the car: Its a 1977 Porsche 924. It was my daily driver back in college. I'm its second owner. I have spent the last few years getting it ready to race in the SCCA, ITB class. Its been stripped down, a roll cage has been installed along with a fuel cell (cause dieing a fiery death isn't fun) Racing gauges and controls have been installed, major suspension work, and a custom exhaust system have been installed.

I still have more suspension work to do, along with the engine replacement, and maybe a fire suppression system.

More updates to come.

NBC+United=No Sleep

2007-10-01T00:36:00.001-04:00

I fly alot. Some times I fly red-eyes. I don't mind them that much, usually. This last flight from SAN to IAD really pissed me off. The flight left at 10:10 PST. That means we were in the air at about 11:00 PST after all the fucking about on the ground was done.

Thats not my normal bed time, but no prob, its been a long night, so fuck it. May as well try to sleep.

After about 10 minutes I realized that was not going to happen. The in-flight Hollywood turd-sandwich of a move was on... The Fantastic Four, Rise of the Silver Surfer needed to be shown to a flight full of adults wanting to go to sleep and the brightest LCDs ever invented (even if they had a viewing angle of +/- .05 deg)

First a bit about the movie, then on with the rest of my rant. TFFRSS (even as an abbreviation the title is too long) is the worst movie ever made. The dialog must have been written by Stephen Spielberg's 8 year-old daughter, cause it made the Phantom Menace seem like fucking Shakespeare:

"It is known by many names. My people call it - Gah Lak Tus, The Devourer of Worlds. It must feed on energy to survive, both thermal and organic." Says Gollum who after getting a surfboard that turns him silver. Its also known as the black cloud from the 5th Element.

Anyway, it was so bad, I had to watch it to the end. The silver surfer explodes, and kills the planet eating cloud. There, now you don't have to see it. Spoiler Alert BTW.

So after that turd of a movie ended, The TVs went dark, and finally I could get some sleep.

After about 15 minutes, the airline waitress realized that "Hey, these people look comfortable and relaxed, NBC will be pissed we aren't force feeding them advertisements. So in the tape goes, and we get exposed to NBCs new season line up.

FUCK.

I cant sleep when TVs are on.

So here it is, the show everyone needs to watch on NBC, Quantum Leap! Except it takes place in San Fransisco, Doesn't have a computer named Ziggy, is called Journeyman, and blows donkey balls. It consists of this albino flashing back in time and wondering why his cell phone wont work, over and over again. Seriously there were like 25 shots of his cell phone with no signal. Maybe he can go back in time and kill Jeff Zuckers parents and save us from this garbage

So, I watched crappy ass TV all the way back to IAD

WTF? I'm I the only person to try this?

2007-09-22T03:31:00.000-04:00

It's my second post! It come right on the heels of my first post. This would have been my first, but I though it was more appropriate that the first post be a bit more meta.

So, on to the real point.

I use Linux a lot for work. Its pretty cool. Its cheap, flexible, and cheap. Lots of people write cool things to do with it. Some people claim to write cool things to do with it, but really write shit that doesn't work. Then they convincing people to waste all night trying to get it to work because its the "the next big thing." If the sadist trying to install this next big thing actually gets it to work, they are supposed to tell people how they it. This is the open source model.

Here is more detail of how the model works:

Find cool app.
Look for a RPM for you're flavor of Linux
Find out that there is no RMP for you flavor of Linux (Why they hell would there be an RPM for Redhat? Who the fuck uses that?)
Download the source.
Attempt to compile the source through some kind of new app, cause ./configure; make; make install is too 2004.
Source fails to compile because your missing LIBCUNHEARDOFLIB-DEVEL_2.9.2134241-53
Goto step 2.
Give up. Wait for some one else to do it.

The 2-7 loop can literally go on for days. Step 8 can last from 1 week to infinity.

I'm on day 2 of trying to get iFolder Server to Compile on RHEL 5. So far after downloading and installing piles of RPMs and compiling SRPMs, I have rolled my own RPM for libflaim-4.9.989-1.i386.rpm. That right. If you want libflaim-4.9.989-1.i386.rpm for RHEL, you have to get it from me!

I don't know what it is, what it does, who wrote it, and why I need it for iFolder, but after hours of work, thats what I have, some kind of 'f'lame library.

I have now contributed something to the opensouce community. Don't say I haven't done anything for you. Now pull your heads out of your asses and start making RPMS for RHEL.

WTF? Blogs==Websites for unwashed masses

2007-09-22T03:03:00.000-04:00

Remember the days when you had a "website" and not a "blog." Remember when you had to write your own HTML back in the old web 1.0 days (or the 0.9 days if you go all the way back to '94 where all there was was Mosaic and all there was to look at was blink text and ugly ass back grounds.. kinda like myspace with out the terrible music.)

Anyway those days are over. Anyone can now tell the world what they think, and now, via myspace, force people to listen to simultaneously their shitty ass band while they yammer about there highschool in a blurry video.

Its too bad. Having to know HTML was a nice flood gate.

So, that being said, this is my "automatically generated webpage" or AGW for short. I will never bring myself to say I have a blog. AGW is as close as I will get.

Why have a AGW? Can't I write HTML?

Yes, I can, but I'm lazy.