Ubuntu Linux

[WanderingKnight]

Not to side-track this too far, but is anyone familiar with ZFS (the partition type)? Any comments on it? It sounds pretty exciting, but all of the nuances and problems never come out until it hits the masses. The features that Sun has been trumping up sound pretty neat, though. The big selling point being that data is always recoverable...

Didn't Sun say that they would be making ZFS Open Source in the near future (in order to have it coded into the Linux kernel)? I'm sure I read that in Slashdot some while ago, but I can't find the news...

At any rate, there is a way to make use of ZFS under Linux, called ZFS on FUSE. Looks like, instead of having it into the kernel, it is used as a separate process in userspace. I don't know how much success these guys have had with it, though.

[Ledgem]

I think that's the goal. I'd heard of the ZFS on FUSE but I'd rather wait until it's an integrated solution. I became a bit excited over it when I heard that OSX 10.5 would allow it as an option (although after Sun announced that, Apple said it wouldn't be possible, so... who knows). But then, I've also heard that ZFS is great for servers, but bad for desktops. Or was it the other way around? Something about a performance hit to the system... I don't remember exactly.

I suppose it's too new at this point. I'm looking forward to its widespread availability, though.

[Dhomochevsky]

Yes, I read something along the line on slashdot.
Like always, the discussions in the comments were much more interesting than the actual cause.
There were some people claiming that linux is in need of a new file system. Now I have never payed much attention to the file system. Its were i store my data right?
Very basic thing you would think, 1s and zeros. It seems I was wrong.
I still dont see where the problem is with current systems, but they suggested Suns system could fill the hole, when its finally open source.

[grey_moon]

I remember reading that ZFS had better performance for large file systems, but ext3 was more robust. TBH selecting a file system is a difficult thing as there is a lot of opinion out there on what is better, and a lot of the opinion is about very minor differences that would not affect an average user (for example speed of access).

When selecting a FS I would always go for maturity - bleeding edge and my data? no way.

Support from the distro - I generally don't like hacking stuff into the kernel even if it is modular as it tends to break when the kernel updates and a broken FS royally sucks, but most distro's do let u boot to the previous kernel

Supported by your applications - Only really affects apps that work on a lower level like imaging, backup or data recovery software. How many of u admins have been stung by leaving the backup till last and finding it doesn't support that server u spent all morning building (/me raises hand)

Supported by the developers - Really important here, for example ReiserFS is in some serious trouble, as version 3 doesn't get any real updates and 4 is so bleeding edge its scary. The main dev is in some trouble in regards to his wife and murder (so I have read)

Ease to recover data - I hope it never will happen but always best to be prepared. FS that use evms are a lot harder to recover from then lvm.

After all of that my fs of choice is ext3, and I can't really see the benefits of using something like ZFS in a desktop, maybe for an enterprise solution.

[grey_moon]

One of the main problems with Linux I think is the amount of choice we get. It would be nice I think to share our windows replacements Here are some for me:

Gaim - Replaced Trillian for a consolidated chat
gwget - Replaced Free Download Manager (FDM still has much much more functionality)
Kiax - Replaced my Tesco Internet Phone (Much better quality and stability)
Comix - Replaced CDisplay to let me read manga

And the big one for me was....

Gnomad2 - Replaced the crapware that syncs my Creative Zen, so much faster and more stable now.

Waiting for...
Google Talk native in Linux (for file transfer)
Skype video

[Ledgem]

GAIM is on Windows, but it does feel slightly out of place (although I much prefer it to anything else). I do wish that they'd spruce up the GUI a bit, though. When I started using my Mac system, I went to Adium based off of GAIM's recommendation (there is no GAIM for Mac OS X). Adium just makes GAIM (now Pidgin, sorry for not calling it that) look so unpolished... it'd be nice if Adium/Pidgin had video support, but I know that's a rough one, and none of the IM companies care to make it easier on them to implement it. Although supposedly Google was going to work on getting video into the libgaim library...

[hobbes_fan]

Hey I've just installed Ubuntu on my htpc again, and I'm having serous issues with playback Ok, Whenever I switch subtitles in either xine or totem with ogm/mkv file formats, the system lags and shuts the app down. If i don't switch subtitle tracks it plays happily no probs. (particularly files with xvid and h.264 video streams audio streams are generally MP3,OGG). (I usually re encode subtitles if they are difficult to see as I am red/green colourblind, I can't see red against a green backdrop and green against a red backdrop, occasonaly I have difficulties seeing stuff of another colour against either a red or green backdrop and yes XMAS time is a PITA for me.) There should be more than enough system resources to handle this with a dual core processor 2 gigs of ram and a 7300gt. And yes the I have the Nvidia binary drivers installed and they seem to be working fine.

Now before anyone says use VLC, it works in VLC but the subtitles are rendered horribly sometimes taking up half the screen occasionally.

Also with xine and totem whenever I set it to fullscreen mode green artifacts on the left hand sde of the screen are rampant on h.264 file formats.

I gave up on mplayer as it kept giving me an error about failing to initialise -vo device, whatever that means.

Any suggestions? Any way to diagnose the problem?

I also need to install a DTV tuner card but I'm not looking forward to that if I can't get this sorted out.

edit: got mplayer to work all is good except for dtv

[WanderingKnight]

I gave up on mplayer as it kept giving me an error about failing to initialise -vo device, whatever that means.

Fire up your mplayer, go to Preferences--->Video and in 'Available Drivers', select xv. That should solve the problem.

By default, mplayer doesn't load custom subtitle formats. If you want to do so, go to ~/.mplayer/config and paste the following:

sid=0
ass=1
embeddedfonts=1
correct-pts=1

Good luck I have been using mplayer for a long time and I've found little to complain about.

(Note: you need to have the codec files for mplayer to work properly. Check the mplayer homepage for info).

[hobbes_fan]

Originally Posted by WanderingKnight

Fire up your mplayer, go to Preferences--->Video and in 'Available Drivers', select xv. That should solve the problem.

It was in xv had to play around with other available drivers. gl2 worked for me. (Now what gl2 is I have NFI but it works and I'm not complaining)

I'm happy with the way Mplayer renders subs. white with a thick black outline unlike the craptastic nature of VLC subs which have little to no outline. And they're big but not eating up 3/4 of the screen more like 1/5 which is perfect.

[Phantom-Takaya]

Here's a weird event that I seem to be having. I have onboard sound and a PCI sound card. It seems that sometimes, Ubuntu likes to play musical chair and pick the onboard sound output to use. Due to this, I can't seem to tell the sound settings to stick with the PCI sound card. I would try to watch videos outside of VLC and the sound output would be on the onboard video.

Does anyone have any idea how to fix this? I know it may be a hardware problem, but I just want to be sure before I go out and throw money at the computer hardware stores.

[grey_moon]

Might be to do with which device the PC initialises first, but it should not be an issue unless they both use the same driver... Is it happening intermittently or during boot?

Can u not disable the onboard card in the bios?

[Phantom-Takaya]

It's intermittent when Ubuntu, itself, loads. Since I dual-boot, I'll add in that Windows doesn't have a problem at all. Originally, I believed it was that the sound card was dying, but when I reinstalled the driver for the sound card in Windows, it gave me no problem at all. So, this is what leads me to believe that it's a software issue.

[Jinto]

Try to find out if the soundcard is listed in the list returned by the command lspci. If it is listed then you'll want to know if its drivers were loaded. Use the command dmesg to get information about driver related stuff. Search for the soundcard in the resulting list. If the soundcard got identified you'll see something like this:

ALSA device list:
#0: ESS AudioDrive ES1868 at 0x220, irq 5, dma1 1, dma2 3

(or OSS device or whatever your system uses)

Since you have basically two sound cards, you should have more then one entry there... #0,#1...

In your desktop application Gnome/KDE you should be able to choose the according device as primary driver. However this approach might be easier imo... if you can switch off the onboard sound in the BIOS then Ubuntu has only one choice to take and cannot decide randomly.

[toru310]

Ermmm I'm not familiar with Ubuntu or anything but are there any known viruses for Ubuntu that can kill windows? Just asking because I know there's are lots of Ubuntu users here..

[WanderingKnight]

Ermmm I'm not familiar with Ubuntu or anything but are there any known viruses for Ubuntu that can kill windows? Just asking because I know there's are lots of Ubuntu users here..

Err, if you know of any loose Linux virus, give me a call. The low market share of Linux in comparison to Windows (5% against 85%) and differences in their internal architecture make coding a virus for Linux not a very promising endeavor. Every virus out there is for the Windows operative system. And most probably, there can be no cross-platform viruses (mainly due to those architectural differences I spoke of).

[SeijiSensei]

Originally Posted by Phantom-Takaya

It seems that sometimes, Ubuntu likes to play musical chair and pick the onboard sound output to use.

The file /etc/modprobe.conf is the first place to look for the devices that trigger the loading of kernel modules at boot. My Fedora Core 6 configuration looks like this:

alias eth0 b44
alias snd-card-0 snd-ca0106
options snd-card-0 index=0
options snd-ca0106 index=0
remove snd-ca0106 { /usr/sbin/alsactl store 0 >/dev/null 2>&1 || : ; }; /sbin/modprobe -r --ignore-remove snd-ca0106
alias snd-card-1 snd-intel8x0
options snd-card-1 index=1
options snd-intel8x0 index=1
remove snd-intel8x0 { /usr/sbin/alsactl store 1 >/dev/null 2>&1 || : ; }; /sbin/modprobe -r --ignore-remove snd-intel8x0

The "alias" directives link a symbol like "eth0" with a kernel module, in the first case my Broadcom ethernet card with the kernel module "b44.ko". I have both an add-in SoundBlaster card ("snd-card-0" using module snd-ca0106.ko) and an onboard Intel chip ("snd-card-1" using snd-intel8x0.ko). All the soundcard modules are stored in /lib/modules/`uname -r`/kernel/sound/. (That "uname -r" command is enclosed in back-tick quotes (`); like all backtick shell commands, it returns the output of the enclosed command as a string. In this case it's the complete version number for the running kernel; mine is "2.6.20-1.2962.fc6".)

I've only installed Ubuntu once and that was on a laptop with no add-in card. Fedora detected both sound chips on my desktop machine, offered me the chance to test both, then asked which I preferred to use. It's never changed since then.

One easy solution might be to force your installation to use just one card by deleting the configuration for the other from /etc/modprobe.conf. I'd also turn off the onboard card completely in the BIOS if that option is available to you.

It's also possible that your drivers are stored as separate files in /etc/modprobe.d. My proprietary NVidia driver is loaded by the file /etc/modprobe.d/nvidia. If Ubuntu put the sound configuration files in /etc/modprobe.d instead of /etc/modprobe.conf, just move the one you don't want to load to some safe backup location (just in case you change your mind).

Originally Posted by Migufuchi Fusutsu

Ermmm I'm not familiar with Ubuntu or anything but are there any known viruses for Ubuntu that can kill windows? Just asking because I know there's are lots of Ubuntu users here..

You mean in a dual-boot situation with both Windows and Linux on the same machine?

Do you have some reason to believe that such a virus exists, or is this just a personal concern? If you've read about some such thing, can you post a URL?

There aren't that many viruses for Linux at all, and nothing that I know of like you fear. If you're careful not to run as the "root" (administrative) user, and you can't mount the Windows partition read/write into the Linux filesystem, then it think it would be very difficult for a piece of software with ordinary user privileges to touch the Windows data. Of course, if you gave a script control as the root user, then yes, it could fill the Windows partition with zeroes a dozen times over then delete the partition using something like GNU parted. I could write a script to do this in well under an hour. If I could get you to trust me with the root password, then I could blow away the Windows partition, or any other partition, or do any of a very large number of bad things.

The issue is trust. I routinely install Fedora Core packages automatically onto my Linux machines without any worries about corruption. They're all digitally signed and stored on well-maintained archives at places like universities. But I wouldn't automatically run a program I downloaded from the Internet, and luckily for me Firefox thinks that's an excellent policy and won't run programs either. And if I do run it, it runs with my user privileges, not the administrative user's privileges as is so often the case in Windows. The whole notion of "drive-by" infections, where something like Internet Explorer can download files that silently modify the system areas of the computer, horrifies me. There's no plausible security model that would allow this behavior, but Windows did (still does?). Once you can load a program onto someone's machine that can phone home, all bets are off about who's really in control of that machine.

That would be true for Linux as well, by the way. There's nothing stopping me from running a program with my user privileges that sends out thousands of emails or pounds a server with web requests. In the email case I'd have some problems as an ordinary user with forging the sender's identity; certainly wouldn't want to use my own! However, running a script that hits a website as fast as possible just requires looping with the command-line "wget" web client.

I leave to others here how MF's hypothetical Windows-eating virus might work on a machine running both OS's as virtual machines under VMware or Xen. Could the Linux VM delete the Windows VM and delete all traces of it from storage? I would assume any well-designed virtual machine manager (VMM) would prohibit all such activities, but how about infecting the VMM itself? I doubt that's very easy to accomplish either.

[WanderingKnight]

I leave to others here how MF's hypothetical Windows-eating virus might work on a machine running both OS's as virtual machines under VMware or Xen. Could the Linux VM delete the Windows VM and delete all traces of it from storage? I would assume any well-designed virtual machine manager (VMM) would prohibit all such activities, but how about infecting the VMM itself? I doubt that's very easy to accomplish either.

Funnily enough, there was a Slashdot article about attacking 'sandboxes' today.

[Jinto]

Originally Posted by SeijiSensei

The file /etc/modprobe.conf is the first place to look for the devices that trigger the loading of kernel modules at boot. ...

Doesn't that only work with Hotplug/Coldplug? (I am not sure, so I ask)
When Hotplug/Coldplug became deprecated in Gentoo I couldn't really use my modprobe.conf (or parts of it anymore) since there would be a warning: Coldplug not found or the like.
Since Udev is doing all the stuff (I supposed any newer Linux distribution should be using Udev now imo):

Originally Posted by Gentoo Wiki

- Udev loads the modules simultaneously, which is much faster,
but can cause some troubles with multiple network/sound/etc devices

/etc/udev/rules.d/ is the important folder for udev (where the rules reside)

Originally Posted by Gentoo Wiki

---------------------------------------------
* Devices get mixed up eg. Network/Soundcards
---------------------------------------------
- Because udev loads all the modules at once, sometimes devices are initialized
in different orders (eg. network cards switch eth0 and eth1, sound cards
the same)

Solution:
- Load them in MODULES=() array in the order you need them
- eg: MODULES=(moduleA moduleB)

Second solution for network:
- The "proper" way to configure net interfaces to hold static names within
udev rules. Add lines like these to a custom rules file such as
/etc/udev/rules.d/01-network.rules:
SUBSYSTEM=="net", SYSFS{address}=="aa:bb:cc:dd:ee:ff", NAME="lan0"
SUBSYSTEM=="net", SYSFS{address}=="ff:ee:dd:cc:bb:aa", NAME="wlan0"

- To get the right mac address use this command:
udevinfo -a -p /sys/class/net/<yourdevice>
- Make sure you use lower-case hex values in your udev rules.
- NAME= determines the name of your network card. Use these names in your
network configuration in rc.conf as well.

in /etc/modules.d/alsa there is the listing of the device names in conjunction with their drivers:

alias snd-card-0 snd-hda-intel

.
.
.

in /etc/modules.autoload/kernel-2.6 are the autoloaded modules (uh did I forget something... hm I think not)

But I assume there exists a wizzard in Gnome or KDE to do this in Ubuntu (I mean it is not so techy like Gentoo).

[SeijiSensei]

In Fedora the wizard is an applet called "system-config-soundcard," but that's a RedHat-ism that doesn't exist in Ubuntu. I don't know what it's called there, but there should be some entry in the menu trees, yes. In Fedora it resides in the "Administration" menu and demands the root password.

My system does use udev to identify devices, but I still have that modprobe.conf file. I also don't have an /etc/modules.d directory; as I said, the various module loaders like my nvidia driver are stored in /etc/modprobe.d on my Fedora box. My brief tour of that Ubuntu box I built suggested it, too, had a modprobe.d directory, but I could certainly be wrong.

[Jinto]

Mhm, that is why I was so vague about the actual way to do it in the first place... but now we provided two versions... if Ubuntu uses one of the two or a mix of the two then a solution can hopefully be derived from the two approaches given. One with Hotplug/Coldplug/Udev and one based on only Udev.