/dev/chat

2:10 PM

Hi is anyone here

0

I set up a user to ssh to Windows Server 2008 R2. I was able to change de default directory. The only piece I could not figure out is how to restrict user to just that directory. In other word I don't want the user to be able to change directory. Please advise. EDIT: This is where I stand:...

I realize my question is better suited for this site how can I migrate it

casey

2:32 PM

@meda if you want it migrated, flag it for moderator attention on SU and ask.

Faheem Mitha

2:50 PM

@casey Is it really more on topic here?

meda

I dont know really

I asked the question last week

no attention

added bounty still nothing

maybe they cant answer it

@FaheemMitha

Faheem Mitha

@meda SU isn't really a place where you get a lot of heavy hitters, as far as I can tell. Or if there are, they seem thin on the ground.

meda

3:21 PM

@FaheemMitha yes I realize that. I chose superuser because the ubuntu guys told me it would be off topic

Faheem Mitha

@meda Yes, it would be OT on AU.

meda

so what about here

Faheem Mitha

@meda maybe try a more specialised forum?

@meda Dunno. Worth trying, I guess.

meda

okay

Faheem Mitha

Not a lot of people using Cygwin here, I think.

Except in desparation, when stuck with Windows.

meda

3:23 PM

yes this is my case

mikeserv

3:55 PM

@Ramesh - so someone has accepted your answer and not upvoted it?

It's only happened to me a couple of times - but I don't think the asker had the points to do the vote.

Ramesh

4:13 PM

@mikeserv, I have noticed it quiet frequently..

mikeserv

frequently? why do they accept your answer then?

Ramesh

not my answers. I mean in general I have noticed.

I have may be 2 or 3 myself. But it is a general trend I have noticed in our site.

mikeserv

And it's not just because asker doesn't have the points or something? I upvote most things worth giving me pause. It's so easy.

Ramesh

Sometimes it is because the asker doesn't have points. But yeah, the asker can come back any time after getting enough reputation and show his thanks to the answerer by upvoting.

mikeserv

That's a little harder though - remembering. That takes commitment.

I don't do a lot of that. I got an upvote this morning from some stack overflow? answer I did like last year. It was fucking awful.

I should fix it. But instead I just commented about how much it sucked.

Ramesh

4:19 PM

I always do it when I search something and end up getting an answer, I upvote it.

mikeserv

Well, yeah, when I find it I do the same.

Ramesh

►

mikeserv

But I probably won't remember to turn around and do it later if I can't at the time for some reason. Your L popped up conveniently under my mouse cursor.

Ramesh

That is a good music to listen to while reading.

Braiam

@Ramesh heh

mikeserv

4:22 PM

That's creepy.

There was an ad for a 10 hour version?

Ramesh

That was from a japanese manga music.

mikeserv

That's commitment.

Braiam

I hope you watched the original

Ramesh

@Braiam, japanese is not the original?

Braiam

@Ramesh kinda, that's the theme for the anime adaptation

@Ramesh yes, it's, you watched the complete series?

Ramesh

4:24 PM

Yeah. I watched it.

It was actually good.

If you were stuck on a desert island with only 5 command-line utilities, which would you choose?

Braiam

@mikeserv It's actually good, the series that gave birth to that track

mikeserv

@Braiam - I believe you. But it's still a creepy track.

Ramesh

@mikeserv @Briam, If you were stuck on a desert island with only 5 command-line utilities, which would you choose?

mikeserv

this whole thing was like one big downvote party:

2

Q: Why is writing SLOW on raw device, and FAST on filesystem (USB key)?

I have a USB key (PQI U822V-Speedy 32G) that I am trying to benchmark quick'n'dirty on Linux. I'm testing write bandwith. dd on raw partition I created a partition starting at sector 2048, then did a 4 GB sequential write: dd if=/dev/zero of=/dev/sdb1 bs=1M count=4096 I get ~22 MB/s. I al...

filesystems performance usb-drive dd raw

@Ramesh - uhhh... finger?

@Ramesh - help?

Ramesh

6

A: What are your best senior level Linux interview questions

My favorite closing question: If you were stuck on a desert island with only 5 command-line utilities, which would you choose? My personal list: ping tcpdump ps lsof strace It's a simple question to see what commands an admin is most comfortable with, and it also helps to demonstrat...

mikeserv

4:36 PM

@Ramesh - I saw that other answer too - about adding a user without useradd palindrome? That was good.

You're really gearing, huh?

Ramesh

@mikeserv yeah. :)

mikeserv

well, you need sh, sed... that's about it.

Faheem Mitha

"The focus on Robin really aloud her character...". What kind of spelling mistake do this call this in English?

mikeserv

Umm... I think that allowed and aloud are homophones.

That's a neat little Venn.

Faheem Mitha

@mikeserv Homophones! That's it.

Gilles

4:39 PM

@meda The security will heavily depend on Windows. So SU is a better place.

I suspect that the answer is in fact to set up the right ACLs in Windows.

Ramesh

Is it necessary to have twice the swap size of RAM? I mean today's systems comes with 32 GB RAM as minimum. Do I need to set the swap size as 64 GB?

Gilles

@Ramesh it's an old myth, I've answered it before, search the site

mikeserv

No. Mo swap mo problems.

Ramesh

@Gilles Thanks. I will look for it.

mikeserv

just ditch it.

Faheem Mitha

4:42 PM

@Ramesh No.

Ramesh

@mikeserv yeah. I saw another interesting question yesterday.

Faheem Mitha

With 32 GB you don't need swap at all.

Ramesh

Something to set noop algorithm for scheduling.

@FaheemMitha Thanks.

mikeserv

Oh. like echo 1 >/sys/someething...

Ramesh

yeah, exactly.

mikeserv

4:43 PM

Or echo 0?

And with sysctl

Gilles

@FaheemMitha no, there's no figure at which you don't need swap. It depends what the machine is doing.

Ramesh

Oh, that actually is a temporary setting I guess. To make the setting permanant, editing /etc/grub/grub.conf file is the solution.

mikeserv

I haven't had a swap partition in years.

eek

What?

You mean the solution was a kernel parameter?

Ramesh

@mikeserv cyberciti.biz/faq/linux-change-io-scheduler-for-harddisk

mikeserv

You should be able to set same in... fstab?

Some disk conf in etc

Ramesh

4:47 PM

That am not sure.

Anyone interested in getting their hands dirty, should give it a try. It's free and has some interesting challenges as well.

trueability.com

mikeserv

I guess its just sysctl.conf

What is trueability?

Are they trying to sell me something? I'm always leary...

Ramesh

@mikeserv, I guess it is a public funded startup.

They give you some free clusters from AWS or some cloud and give you some challenges like configuring web server, firewall etc.

It is a good initiative.

Faheem Mitha

@Ramesh I think you live in a parallel (and nicer) universe. In this one, 32 GB RAM is by no means the minimum.

Ramesh

@FaheemMitha he he. The more the RAM the more the trouble :)

mikeserv

@FaheemMitha - remember the sudo/tar question? I wrote my own tar and updated it.

shitar

Faheem Mitha

5:02 PM

@mikeserv that's a slightly unfortunate name.

Don't call any of your childen that.

mikeserv

Well, it is descriptive. I don't really like naming them anyway. I usually don't care what they're called - just do it, you.

You should check it out though - I basically write out my own tar stream to a pipe with ... less than 10 or so lines of POSIX shell. Well, AND some pretty heavy reliance on a few GNU utils for file metadata.

It does block devs in a stream.

Just cats them, basically.

Ramesh

@mikeserv, ha, you have mentioned about oom_score in your answer.

mikeserv

...?

Ramesh

11

A: Will Linux start killing my processes without asking me if memory gets short?

The truth is that regardless of which way you look at it - whether your process choked up due to the system's memory manager or due to something else - it is still a bug. What happened to all of that data you were just processing in memory? It should have been saved. While overcommit_memory= is ...

mikeserv

I remeber that one.

You can go from +-17 I think.

Ramesh

5:14 PM

yeah. I just came to know about this.

mikeserv

You're looking at the reason I know.

Faheem Mitha

@mikeserv Well, I asked this on english.sx. Because I clearly have nothing better to do, and have no life.

1

Q: What is this kind of spelling mistake called?

Consider the following sentence from this web page (a review of an episode from the TV show "How I Met Your Mother"). "The focus on Robin really aloud her character to get the kind of attention she has been missing for many a season." Clearly, "aloud" should be "allowed". So, the writer has sub...

eggcorn

I guess I'm just a SE groupie.

Ramesh

@Faheem, Once a SE user, I think you will be a life long SE user.

Faheem Mitha

@Ramesh Not if SE disappears into the ether. Nothing lasts forever.

mikeserv

@Ramesh - agreed. Same goes for Yahoo.

Faheem Mitha

5:20 PM

How have the mighty fallen. Sic transit gloria mundi. And so on.

Ramesh

@mikeserv Yahoo question and answers?

mikeserv

No.

It was sarcasm. My apologies.

Faheem Mitha

/me resists the urge to quote Ozymandias

mikeserv

I almost said Napster.

Well, I just learned what an Ozymandius is.

Apparently it's the Sun God's middle name.

Faheem Mitha

@mikeserv It's the internet. You learn something new every day. Or should I have said Stack Exchange? Actually, I think in this case, the credit should go to Wikipedia.

mikeserv

5:24 PM

It does.

Ramesh

@FaheemMitha I like brain fart for the answer.

Faheem Mitha

@Ramesh It's a bit non-descriptive. Covers all manner of sins.

I doubt the english.sx crowd would go for it.

I get the feeling that question is in the process of being closed. If I don't have enough rep, would I not see close votes?

derobert

@mikeserv tar in shell... that's just an awesome idea...

fully portable, no less :-)

Apparently I have to wait a day to award a bounty, though.

mikeserv

@derobert - not fully. It uses all of those Linux utils.

Gilles

@derobert shar, or a tar format implementation?

derobert

5:34 PM

@Gilles tar format implementation

mikeserv

I don't know how else to do get info on unmounted disks.

The syntax is pretty portable probably.

Faheem Mitha

I just realised that in asking this question I've publicly revealed to the world that I watch "How I met Your Mother". How shall I hide my shame?

Hi @derobert.

Gilles

@derobert that sounds awkward. Dealing with binary formats is a pain when you can't store null bytes.

derobert

@Gilles thankfully, it appears you just have to spew them to stdout

3

A: How to convince tar (etc.) to archive block device contents?

So recently I wanted to do this with tar. Some investigation indicated to me that it was more than a little nonsensical that I couldn't. I did come up with this weird split --filter="cat >file; tar -r ..." thing, but, well, it was terribly slow. And the more I read about tar the more nonsensical ...

mikeserv

You know I spent like 1hr this morning trying to get rid of the 512KB read/write dd thing. I thought I would have to write out the padding. But, of course, block devices are already blocked.

Gilles

5:36 PM

@derobert Oh, tar generation, not extraction.

yes, that's easier.

mikeserv

I don't think I could do that.

Gilles

you don't have to handle all possibilities, just generate a valid archive.

mikeserv

Or - I don't think I'd wanna try. You'd have to grep every block or something.

derobert

Or run all through od...

mikeserv

oh yeah!

just skip through, like...

anyway, I'm glad you liked it. it served its purpose for me. but if you use it - and improve it - would you let me know, @derobert?

derobert

5:40 PM

Hah, I think I'd improve it by writing it in Perl :-/

mikeserv

That was what I was hinting at.

derobert

Maybe I should write an Archive::Tar replacement, that streams output.

Gilles

@derobert I think it's called exec python; import tarfile

derobert

Yeah, and next you'll be suggesting writing that in emacs, and it's all downhill from there :-P

Gilles

There are a few bad design mistakes in the Python language, but I really like its standard library

Gnouc

5:45 PM

@Gilles: Can you clarify what are bad design mistakes?

mikeserv

@derobert - yeah - it was actually your talking about that the last time that made me think about looking into doing it myself.

I figured - if Perl is doing it - what the hell is it doing?

Gilles

@Gnouc lack of variable declarations, and lack of closures

mikeserv

As soon as I got a look at the header it was a done deal. I mean... even I can add.

derobert

hah

although... is that a 12-digit octal number for file size?

Wonder what happens if you want a larger file.

mikeserv

ustar supports up to 8G

gnu tar pax can do 9 EB

per file

Gnouc

5:50 PM

@Gilles: "lack of variable declarations", you mean declare before using it?

derobert

must use a different header format then

mikeserv

the formats are just... more of the same.

derobert

yeah

mikeserv

Yeah. The link at the top? It's all there, man. The POSIX pax page.

Gilles

@Gnouc yes

mikeserv

5:51 PM

It's like... everything you didn't wanna know about CPIO/tar/the works.

And by the way - there apparently is no pax that does the shit that page says it should.

Gnouc

@Gilles: How about closure?

I think python has it.

mikeserv

Though GNU tar might.

derobert

@mikeserv wow, that's great. They "solved" the n standards problem with a new standard, and no one implemented it right. Even better than the "now there are n+1 standards problem"

mikeserv

I know - I went there first, believe me.

There's really cool stuff on that page.

It supposed to support options for setting the header while building the archive.

And the -o listopts stuff? That's crazy cool! But nobody does it.

Gilles

Closure (computer programming)

In programming languages, a closure (also lexical closure or function closure) is a function or reference to a function together with a referencing environment—a table storing a reference to each of the non-local variables (also called free variables or upvalues) of that function. A closure—unlike a plain function pointer—allows a function to access those non-local variables even when invoked outside its immediate lexical scope. The following program fragment defines a (higher-order) function startAt with a local variable x and a nested function incrementBy. This nested function incrementBy has...

derobert

5:55 PM

(Searching CPAN, there are apparently some Perl modules to stream tar output...)

Anyway, lunch time.

Gilles

@Gnouc does it now?

GvR was adamantly against them

Gnouc

@Gilles: python decorator use closure, and you can see here: stackoverflow.com/questions/4020419/closures-in-python/…

Gilles

@Gnouc thank you

Gnouc

Guido wrote about python functional, and mention about closure here: python-history.blogspot.com/2009/04/…

Braiam

11:56 PM

@mikeserv what did you expect? Is a 1-2mins long track looped for a hour... it was fine in the series themself, but as lone track, not so much

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