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Ubuntu 16.04 (Xenial Xerus)

releases.ubuntu.com

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Re: Ubuntu 16.04 (Xenial Xerus)

#251

Post by avar »

hatsunearu wrote: post #238
avar wrote: post #124

Earlier quoted context omitted.

You're conflating collision attacks like the Flame malware with a preimage attack that would be necessary to produce a malicious Ubuntu release with the same MD5SUM. I.e. what's "broken" about MD5 is if you have a lot of CPU time and I allow you to give me two unrelated blobs, you can craft those blobs to have the same MD5 sum. What's not "broken" (beyond a theoretical 2^123.4 attack) with MD5 and not broken at all f…

What? Pretty sure you're wrong. Yes, MD5 preimage resistance is not broken (to a reasonable degree). If you have the Ubuntu 16.04 ISO (you do), and if you have its hash, the attack to craft a different ISO with the same hash is a collision attack. A preimage attack is if you had some hash y where y=H(x) where x is some file/whatever, and trying to find out possible values of u that give rise to y when you do H(u), wi…

No. What you're describing is just a subset of preimage attacks.

Not having knowledge of x is just one type of preimage attack, a "preimage resistance". You can also know x, then it's a "second-preimage resistance".[1]

Which is not the same as a collision attack. Where you're trying to find x and y such that h(x) = h(y) without anyone specifying x or y in advance.

By definition a collision attack is an attack where you specifically craft both x and y such that they exploit weaknesses in the algorithm.

It's not enough to know an arbitrary x or y that someone else has made, because that value isn't going to be exploiting the weakness.

1. https://en.wikipedia.org/wiki/Preimage_attack

Re: Ubuntu 16.04 (Xenial Xerus)

#252

Post by dolguldur »

patwolf wrote: post #55
themodelplumber wrote: post #40

Earlier quoted context omitted.

This reminds me, I'd really like to know what to expect with a 4K monitor in 16.04.

I've been running 16.04 beta for the past month on a Thinkpad P70 with a 4k display, and scaling has been great. The OS UI elements (like menu bars) can be scaled to any size. Most applications seem to work out of the box. The ones that have given me the most problems are a handful of desktop apps implemented in an embedded browser (like Spotify) where I have to set an extra command flag to properly scale.

I'd be curious to know what happens in a mixed-DPI setup, e.g. internal 4K screen and external 1080p screen.

Re: Ubuntu 16.04 (Xenial Xerus)

#253

Post by fpgaminer »

I gotta say, Canonical/Ubuntu has a lot of respect in my book for how dependable the distro has been over the years. I've been through my fair share of distros, and one of my employees goes through a new Linux install at least once a week. Ubuntu is one of the few distros that almost always works. Other distros will have one problem or another with this machine or that, but put Ubuntu on there and everything is fine (well, as fine as Linux gets).

A few weeks ago I had to dig up an old 12.04 machine and bring it back to the modern age. Much to my surprise, I was able to upgrade it all the way to 15.10 with minimal hassle. While the normal apt repos were dead for 12.04, Canonical keeps around an archived mirror. So you just edit the sources file to point at the archive, and then you can upgrade from there. Impressive.

Not that Canonical/Ubuntu don't have their warts. The Amazon fiasco, Unity, their cloud services, etc. And at the end of the day it's still Linux, with all the problems that brings. But, all things considered, I rate Ubuntu as the best of the bunch and feel grateful for the gift they give to the community.

Re: Ubuntu 16.04 (Xenial Xerus)

#254

Post by bsg75 »

bsg75 wrote: post #188
davidmichael wrote: post #146

Earlier quoted context omitted.

I haven't tried it but I think if you do a manual install and format disks as zfs you could have a zfs root filesystem with 16.04.

There was an issue in the beta where the installer would not recognize ZFS volumes for the boot installer. Will be verifying if still an issue as soon as I can.

https://github.com/zfsonlinux/pkg-zfs/wiki/HOWTO-install-Ubu...

https://github.com/zfsonlinux/pkg-zfs/issues/188

Re: Ubuntu 16.04 (Xenial Xerus)

#255

Post by paulddraper »

fpgaminer wrote: post #253

I gotta say, Canonical/Ubuntu has a lot of respect in my book for how dependable the distro has been over the years. I've been through my fair share of distros, and one of my employees goes through a new Linux install at least once a week. Ubuntu is one of the few distros that almost always works. Other distros will have one problem or another with this machine or that, but put Ubuntu on there and everything is fine…

Yeah, take Ubuntu and their repos, throw out Unity, find a way to get a Java release from the last few years, do the graphics drivers dance, and you have a very solid, reasonably compatible development environment.

Re: Ubuntu 16.04 (Xenial Xerus)

#256

Post by raarts »

oblio wrote: post #178
stegosaurus wrote: post #85

Earlier quoted context omitted.

My experience of Windows 10 is limited to having a look at it in local computer shops (I've been trying to find a decent cheap laptop to stick Linux on for a friend). I clicked the Start Menu. Fully half of it was made up of flashing animated crap - things moving about, very colourful adverts, the actual things I wanted to do were obscured by it. I tried a few machines. They did the same thing. Maybe it's a manufactu…

The Start menu in Windows 10 can be configured in about 2-10 clicks to stay put.

Poor choice of default settings.

Re: Ubuntu 16.04 (Xenial Xerus)

#257

Post by RaleyField »

stegosaurus wrote: post #85
themodelplumber wrote: post #42

Earlier quoted context omitted.

Curious what you want to remove in Windows 10. Not an evangelist, just set it up on a dual-boot refurb for a friend and thought the initial experience wasn't bad.

My experience of Windows 10 is limited to having a look at it in local computer shops (I've been trying to find a decent cheap laptop to stick Linux on for a friend). I clicked the Start Menu. Fully half of it was made up of flashing animated crap - things moving about, very colourful adverts, the actual things I wanted to do were obscured by it. I tried a few machines. They did the same thing. Maybe it's a manufactu…

Right click, turn live tile off. I don't know why you even bother with Linux if you didn't even try the first logical graphical gesture that one can reasonably expect to lead to fixing this problem. You can even remove most/all default tiles, like any sane poweruser would do. The same as in Windows 8. On live tiles - Apple has dashboard that has seen more success than widgets on Vista+, Microsoft decided to push some of this functionality on live tiles, so that you can have an app launcher that doubles as a widget when you want to display information on it, but that functionality is optional. If it was off on all default tiles then nobody would know about it, so it'd be a bad default.

What I'd want to know about Windows 10 though, and Google seems not to deliver anything beyond bullshit articles on how to disable it or useless scaremongering blogspam - clearly enumerated and sourced list of information telemetry subsystem captures and sends back to mothership and what parts can be reliably disabled without resorting to shady third-party apps.

Re: Ubuntu 16.04 (Xenial Xerus)

#258

Post by hatsunearu »

avar wrote: post #251
hatsunearu wrote: post #238

Earlier quoted context omitted.

What? Pretty sure you're wrong. Yes, MD5 preimage resistance is not broken (to a reasonable degree). If you have the Ubuntu 16.04 ISO (you do), and if you have its hash, the attack to craft a different ISO with the same hash is a collision attack. A preimage attack is if you had some hash y where y=H(x) where x is some file/whatever, and trying to find out possible values of u that give rise to y when you do H(u), wi…

No. What you're describing is just a subset of preimage attacks. Not having knowledge of x is just one type of preimage attack, a "preimage resistance". You can also know x, then it's a "second-preimage resistance".[1] Which is not the same as a collision attack. Where you're trying to find x and y such that h(x) = h(y) without anyone specifying x or y in advance. By definition a collision attack is an attack where y…

yeah, you're right. my bad.

Re: Ubuntu 16.04 (Xenial Xerus)

#259

Post by criddell »

takno wrote: post #225
criddell wrote: post #221

Earlier quoted context omitted.

> I'm currently getting 7 hours out a commodity Asus with a couple of dev environments and a VM running Wow, that's very good. I've always found running a VW absolutely destroys battery life. For laptops, I've only ever managed to get 9+ hours on a Macbook and that's pretty much the threshold that I'm comfortable with to leave with a laptop as my work machine for the day. If you're getting 7+ on your Asus running a V…

I'm actually not sure the VM is making that much difference, which is surprising, although it's pretty much only running nginx, and having all the bare-metal virtualization stuff enabled has helped a lot with performance. This is with core-M, so in many ways the things to watch out for are screen brightness and anything which makes the processors ramp over 800mhz - that actually seems more damaging than processes tha…

Are you using the laptop mode tools or tlp? Any packages in particular that you would recommend to reduce power consumption?

BTW, my VM was running Windows and that's probably why it drained my batter so quickly.

Re: Ubuntu 16.04 (Xenial Xerus)

#260

Post by stegosaurus »

RaleyField wrote: post #257
stegosaurus wrote: post #85

Earlier quoted context omitted.

My experience of Windows 10 is limited to having a look at it in local computer shops (I've been trying to find a decent cheap laptop to stick Linux on for a friend). I clicked the Start Menu. Fully half of it was made up of flashing animated crap - things moving about, very colourful adverts, the actual things I wanted to do were obscured by it. I tried a few machines. They did the same thing. Maybe it's a manufactu…

Right click, turn live tile off. I don't know why you even bother with Linux if you didn't even try the first logical graphical gesture that one can reasonably expect to lead to fixing this problem. You can even remove most/all default tiles, like any sane poweruser would do. The same as in Windows 8. On live tiles - Apple has dashboard that has seen more success than widgets on Vista+, Microsoft decided to push some…

I think you missed the part of my comment that mentioned me being in a computer store - I just played with it for ten seconds to check out the keyboard and touchpad of the machines, I have no plans to use Windows 10 thus no need to try to disable it. Useful to hear that it is possible though! :)

WRT disabling telemetry - probably the best way to go about it would be to set up a firewall or similar and try to kill all outgoing to microsoft.com. Turn it back on for updates and hope that they don't just send everything then, I guess. Disabling individual parts sounds like a losing game - you're running an MS kernel, if they want to do it they'll just do it.

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