Root Access

XKCD

5:17 AM

And I was kicked out of my March Madness pool because I wouldn't shut up about the evidence for NBA/ABA endosymbiosis.

djsmiley2k TMW

7:59 AM

hmmm wtf youtube just told me to restart my computer.

/me restarted chrome and that fixed it

bertieb

8:53 AM

I get that sometimes when something happens with the audio renderer

or when I mass upgrade packages

is there a way to live-swap the default card in ALSA?

usually my spakers are default

but rarely it seems to select my headphones

Burgi

morning

2

bertieb

or is the answer to "how to change the default audio device in ALSA?" something along the lines of "use pulseaudio" ?

oh hmm

it appears the mobo audio is't in /proc/asound/cards

odd

djsmiley2k TMW

9:11 AM

@bertieb there should be

bertieb

9:25 AM

@djsmiley2kTMW "Tell me, Mr Anderson... what good is being able to swap cards, if one of them isn't there?"

djsmiley2k TMW

:D

bertieb

I could try and figure out why the onboard audio sometimes fails to show up

or I could reboot in those... ~5% of occasions

the latter is unsatisfying but also much less likely to take up a full day of diagnosing ;-P

djsmiley2k TMW

Does it only show up, when a headphone is connected?

bertieb

My speakers are plugged into the mobo audio; HS is a usb G930

Both are always plugged in

djsmiley2k TMW

but sometimes the usb doesn't show up?

bertieb

9:32 AM

Sometimes there is no audio when I boot; I had assumed that was because of card default switching, but I checked there and there was no onboard audio reported by /proc/asound or aplay -l

@djsmiley2kTMW Other way 'round

onboard audio sometimes doesn't show up

djsmiley2k TMW

ooo, weird

bertieb

yup!

a quick grep of dmesg didn't show anything obvious

but my analysis was hardly forensic

djsmiley2k TMW

nod

deffo weird.

bertieb

Aye

I'm inclined just to ascribe it to a random BOFH excuse calendar reason

djsmiley2k TMW

ytup

solare flares! (french ones no less!)

bertieb

9:42 AM

B-bu-but Brexit!!

DavidPostill

@bertieb I thought you Scots were going to vote again to stay in?

bertieb

'twas a joke

kinda like Brexit, a bad joke

And Scotland probably would vote to rejoin

Dunno though, politics is notoriously fluid

Burgi

@DavidPostill dude! you've changed your face

DavidPostill

@Burgi Yeah, got bored with the old one ;)

Burgi

like it :)

DavidPostill

10:01 AM

Last one was a passport photo so a bit formal and posed. This one is more edgy ;)

DavidPostill

10:31 AM

Watch as plane lands sideways after battling crosswinds

►

bertieb

11:08 AM

I have an ssh pubkey on a jumphost, and the target machine

and ~/.ssh/config set up correctly

so ssh target works using my private key without prompting for a password

djsmiley2k TMW

bertieb

ie: it uses the key to log in to jumphost and target

all that works correctly

why does it prompt for the password on jumphost if I do

ssh -i <id_rsa> -j jumphost target ? (as root)

djsmiley2k TMW

:/

it's asking for the password, for target?

aaah y u ssh as root ;)

bertieb

Because this is a service (borgmatic)

which runs as root

djsmiley2k TMW

I think, because you haven't loaded the .ssh/config when you're connecting

so it doesn't know about the key too maybe

/me hasn't used -j

bertieb

11:12 AM

@djsmiley2kTMW it shouldn't need that as I've specified the jumphost using -J

accidentally had it as -j (lowercase) in example above

djsmiley2k TMW

does it load the key from the jumphost, or locally?

bertieb

locally

the identical command runs correctly if I run it under my own user

okay, so -vvv shows me that it doesn't seem to want to load the privkey when connecting to the jumphost

question is... why not?

djsmiley2k TMW

### Host to jump to via jumphost1.example.org
Host contabo
HostName contabo.example.org
ProxyJump contabo

tecmint.com/access-linux-server-using-a-jump-host

I'm confused as I've got nothing to test on atm :P

bertieb

So if I set User and IdentityFile in root's .ssh/config, and use that instead of -J, it works

which is grand, and will work for my purposes

but I am curious as to how to specify the same options on the command line

or why one cannot

As the resident expert on ssh jumphosts, would you mind weighing in on the above when you see this ping, @CanadianLuke ?

Thanks in advance :)

Burgi

12:12 PM

@DavidPostill i saw that

djsmiley2k TMW

2:57 PM

Starlink Mission

►

Starlink launch in -8min

Not Informat

Community working group updates: February 2020

The Community Team on February 17, 2020

In this post, we’d like to talk about some of the initiatives that are happening internally at Stack Overflow aimed at addressing and repairing our relationship with our community.

Burgi

...

bwDraco

4:54 PM

0

Q: Accuracy of FSIN and other x87 trigonometric instructions on AMD processors

On Intel processors, x87 trigonometric instructions such as FSIN have limited accuracy due to the use of a 66-bit approximation of pi even though the computation itself is otherwise accurate to the full 64-bit mantissa of an 80-bit extended-precision floating-point value. (Full accuracy for all v...

I haven't posted on Stack Overflow in ages...

djsmiley2k TMW

5:23 PM

introducing the youngest to the wonders of colin furze

bertieb

Of the, uhh, Furzels

djsmiley2k TMW

do you not know who...

bertieb

Nope

> Colin Furze is a YouTube personality

welp

I feel okay about not knowing that :D

Burgi

Shocking News! Youtubers Have Personalities!

More on BuzzFeed

djsmiley2k TMW

he's awesome tho

engineer and madman

FIRING 1000 ROCKETS AT 1000 ROCKETS

►

not much engineering in this video, admitidly.

rocket powered tuktuk!

bertieb

5:31 PM

I am the Garth Marenghi of YouTube

In that I have created more videos than I've watched

man, I miss Darkplace

djsmiley2k TMW

do you make anything off them?

bertieb

Does "the warm fuzzy feeling knowing that literally DOZENS of people worldwide have watched some of my videos" count ?

if so, then... no

YT changed monetisation in the last few years, now you need minimum 1000 subscribers before you can start cashing in on that sweet sweet Alphabet dolla

djsmiley2k TMW

oh yah

Canadian Luke

@bertieb I'm back. What's the issue with your jump host? That it's not loading your key automatically?

bertieb

5:46 PM

@CanadianLuke Pretty much

Canadian Luke

Linux client -> Jumphost -> Target server?

bertieb

# ssh -i id_rsa user@jumphost user@target (root; does not use key)

$ ssh -i id_rsa user@jumphost user@target (user; does use key)

Canadian Luke

Is user the same on the jump host, as on the target machine? Same as your user on the Linux client?

bertieb

# ssh target (all config done in /root/.ssh/config; does use key)

@CanadianLuke Yes, although first case it is root that is running ssh client, though connecting as user

Canadian Luke

What all is in your /root/.ssh/config file, in relation to the jump host and your target?

bertieb

5:50 PM

@CanadianLuke Nothing, in the case of wanting to specify all on the command line (via -i and -J)

and <appropriate entries>, in the case where it works

I should make clear that I have this working using .ssh/config

I am just curious why it doesn't work when specifying options on the command line

Not sure if that's intended behaviour / perhaps .ssh/config can specify things that the command line cannot

my impression was that the config file was there for convenience

and that anything one could do there could also be done via command line

Canadian Luke

It can, but you can also use -o SettingNameFromSSHConfiguFile Value on the command line as well

But I use -A to pass my agent from my client through to my target machine

bertieb

Ah, maybe that's what's needed

Canadian Luke

I never heard of -J

bertieb

seems like a convenience switch for jump host

-J destination
         Connect to the target host by first making a ssh connection to the jump host described by
         destination and then establishing a TCP forwarding to the ultimate destination from there.  Multiple
         jump hops may be specified separated by comma characters.  This is a shortcut to specify a ProxyJump
         configuration directive.  Note that configuration directives supplied on the command-line generally
         apply to the destination host and not any specified jump hosts.  Use ~/.ssh/config to specify con‐

> Note that configuration directives supplied on the command-line generally apply to the destination host and not any specified jump hosts.

welp

there's your problem! (dot gif)

Canadian Luke

So try with -A when you have the keys loaded in your ssh agent

djsmiley2k TMW

6:02 PM

2

Q: SSH config option to use ProxyJump gateway's `/etc/hosts` lookup?

I'm attempting a gateway hop through servers A -> B -> C, and would like to have this connection as an entry in my SSH config. SSHing from B into A works. And then from B to C works. As does ssh B -t ssh C. However, when I attempt use the following SSH config file, it fails. Host B Hostnam...

ssh

@bertieb u socking?

Also HarryMC seemingly doing genuine debugging with a user!?

DavidPostill

@djsmiley2kTMW Yeah, so he post an answer and earn the bounty ... :/

djsmiley2k TMW

if it actually helps the user...

its more effort than he normally gives

Journeyman Geek

6:19 PM

That's a positive 😁

bwDraco

6:31 PM

I just ran the utility here on a laptop with a Ryzen 7 2700U and it looks like AMD Zen indeed uses 66-bit pi, because the output of fpuaccuracy examples for the "sin near pi" case is the same as the example output supplied with the program, which was run on an Intel Core i7-2600 (Sandy Bridge). I'm presently away from my Zen 2-based desktop (Ryzen 9 3950X) but will test it when I get a chance. I doubt the result is going to be any different, though. — bwDraco 5 mins ago

...welp.

djsmiley2k TMW

9:29 PM

@CanadianLuke me neither.

and I know about tunnels and such, never ever heard of jumphost option, is it newish? :S

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