Root Access

allquixotic

12:06

> sean@root:~$ uptime
07:06:17 up 206 days, 13:39, 1 user, load average: 0.34, 0.57, 0.63

and i rebooted it manually for linux-vserver kernel install 206 days ago

so, 100% uptime

@OliverSalzburg funny stuff. @Bob tells me I have too many local computing devices (tablets, laptops, etc) -- which I agree with. but he has too many servers. :P

Oliver Salzburg

@allquixotic And he logs on to all of them as root!

allquixotic

I have one dedi server that's up all the time; one much cheaper and lower-end dedi server that I rent for a friend (I don't personally use it hardly ever); and an Amazon EC2 Micro instance that's down all the time unless I need a private proxy to Europe

(so I only pay for the small amount of storage I use on it every month, which is like a couple pennies)

Bob

@allquixotic Well... the total cost of those is like a tenth (excluding the dedi) of one of your local devices :P

@OliverSalzburg Eh. I set up vservers and user accounts on the dedi. The others? I don't care about them.

What's the difference if I log in as root or not? None at all, as far as I'm concerned.

Oliver Salzburg

@Bob Which is basically exactly the problem :D

Bob

@allquixotic Pretty much, mine last went down when I restarted it. 'course, I forgot why...

@OliverSalzburg Hm?

Oliver Salzburg

12:13

You don't disable UAC, you don't run your browser elevated, you don't log on as root

Bob

Password login is disabled, so no brute-forcing.

@OliverSalzburg This isn't my daily-use computer now, is it?

I don't go browsing on a VPS either.

I don't run random programs on a VPS (well, ok, I do, but going in with the knowledge that I can just wipe the whole thing at any time, and there's nothing important on there).

allquixotic

@Bob I still think linux-vserver is the best container solution available right now. OpenVZ is technically better (better isolation and fewer surprising behaviors), but they simply refuse to move off of 2.6.32, which is ancient history by now, so until they move to something more modern, screw them

and LXC simply refuses to make itself secure and isolated

Bob

@allquixotic Unless you don't use root, of course.

Which kinda defeats the purpose of a container.

Oliver Salzburg

@Bob The point is that if you use sudo instead, you're less likely to accidentally run a command with highest possible privileges

Bob

@OliverSalzburg What happens if I accidentally run a destructive command?

I go on over to SolusVM or whatever the control panel is, click reinstall OS, and wait 5 mins.

Oliver Salzburg

12:15

@Bob That depends on the command, I guess

Bob

@allquixotic Yea, I have no intention of changing the current setup :P

Oliver Salzburg

@Bob Oh, in that case it's perfectly alright then I guess :)

Bob

Point is, those things that are potentially risky (running random programs) I'd probably end up elevating anyway.

And, again, this isn't a daily-use machine. Nor a production server.

allquixotic

I have root login disabled on the physical box of my main dedi, and su and sudo are both enabled but require either the user's or the root account's password

I have root login enabled on a few of the guests for convenience, but I can't really muck up the machine too badly in there

Bob

It's a server I do random crap on, where I really don't care.

@allquixotic Yea, I need to do that actually.

allquixotic

12:18

not even a runaway process can bring down modern Linux :D I had mono (opensimulator) running away at like "9000%" CPU usage (basically a really really long queue of stuff waiting for scheduling time) and I didn't even notice for weeks, and Cavil was working fine, etc

Bob

Hm. @allquixotic Would you happen to know how to completely rebuild a vserver, without actually deleting and recreating it?

allquixotic

@Bob rebuild, as in....? wipe it and put a new OS in it?

Bob

Specifically, keep the network interface settings but wipe the OS.

Oliver Salzburg

Yay blackscreen gone \o/

allquixotic

@Bob not sure

Bob

12:19

Hm. I could just back up those settings, I guess.

allquixotic

yeah, copy the file out of /etc/vservers (or wherever you're keeping it)

"the file" = the vserver config file

or am I getting it confused with OpenVZ... argh

anyway, gotta go, be back when I'm at work XD

fixed my damn shift key this weekend, so at least I accomplished something... pulled up the key cap with a bottle opener, blasted it pretty hard with compressed air, obliterated things like hair and dust, put it back together, works fine

Bob

@allquixotic Nah, the entire /etc/vservers/servername/ directory is where the settings are stored

interfaces, fstab, etc

allquixotic

it was so annoying having RShift just not do anything randomly

Bob

the OS is in /var/vservers/servername/

allquixotic

something similar to that implement (the one that's sticking out) -- awesome for removing keycaps

mine is thinner and has almost a hook on the end

Bob

12:24

or you could just get a keycap puller :P

Oliver Salzburg

@allquixotic That's a screwdriver

Bob

I used to pry them out with a nail clipper handle

these things:

Oliver Salzburg

I bought a key puller months ago in the hopes of cleaning my keyboard. There's just never a good time to do it. Whenever you're awake, you need your keyboard :P

Bob

I just realised I have no idea what my root password even is

CBenni

12:39

so, when using django (which uses SQLite), wouldnt it be easier to just use SQLite for my bot instead of PGSQL? Or would it be easier to change the database django uses to PGSQL?

Bob

@CBenni Any reason you need to use postgres?

CBenni

nope

Bob

Is it just a local bot?

Small project?

CBenni

I used it for my first test app, was nice, but I have to rewrite anyways

Bob

No plans for multiple bots or a distributed network?

CBenni

12:40

fairly small, local database

nope

Bob

Then you can use SQLite.

SQLite is fine until you need multiple users, or high concurrency, etc.

CBenni

:D The webpage/django running on SQLite and the bot wont intersect?

Bob

Or a very large DB, I guess.

CBenni

ah, nah, its fairly small

Bob

@CBenni Well, you'd ideally have the bot as a separate program.

CBenni

12:41

database size of like max 10 gigs

Bob

SQLite doesn't run a database server.

It's a plain file :P

CBenni

oh

Bob

@CBenni ...that's not that small

CBenni

yeah, but the database of that size would be generated over several months

or years

Bob

I mean, it's within theoretical limits: sqlite.org/limits.html

CBenni

12:42

I have had the bot running for a few hours (like 100 or so) and the database is ~200 megs in size

Bob

> Every database consists of one or more "pages". Within a single database, every page is the same size, but different database can have page sizes that are powers of two between 512 and 65536, inclusive. The maximum size of a database file is 2147483646 pages. At the maximum page size of 65536 bytes, this translates into a maximum database size of approximately 1.4e+14 bytes (140 terabytes, or 128 tebibytes, or 140,000 gigabytes or 128,000 gibibytes).

This particular upper bound is untested since the developers do not have access to hardware capable of reaching this limit. However, tests…

CBenni

lol

Bob

The problem is performance.

CBenni

mh

Bob

3

A: Maximum number of rows in a sqlite table

I have SQLite database 3.3 GB in size with 25million rows of stored numeric logs and doing calculations on them, it is working fast and well.

CBenni

12:44

yeah should be fine xD

Bob

@CBenni So, 200 days?

CBenni

one table never exceeds 500k lines

Bob

@CBenni Another thing is SQLite restricts future expansion ab it.

You don't need more now, but what about later?

1

A: Maximum number of rows in a sqlite table

I have a 7.5GB SQLite database which stores 10.5 million rows. Querying is fast as long as you have correct indexes. To get the inserts to run quickly, you should use transactions. Also, I found it's better to create the indexes after all rows have been inserted. Otherwise the insert speed is qui...

CBenni

mh. Thing is, isnt SQLite included in python? Therefore, I would have alot less overhead?

Bob

114

A: What are the performance characteristics of sqlite with very large database files?

So I did some tests with sqlite for very large files, and came to some conclusions (at least for my specific application). The tests involve a single sqlite file with either a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices. The idea was to i...

> I tried to insert multiple rows into a sqlite file with just one table. When the file was about 7GB (sorry I can't be specific about row counts) insertions were taking far too long. I had estimated that my test to insert all my data would take 24 hours or so, but it did not complete even after 48 hours.

@CBenni You'd have less overhead on the server, but more work has to be done by your program - there's no external DB server to offload work onto.

pg is pretty light anyway

sqlite just tends to be easier to set up

and more portable

just ship the sqlite file around and you have your DB with you :P

CBenni

12:47

That is pretty cool tho

Bob

64

A: What are the performance characteristics of sqlite with very large database files?

We are using DBS of 50 GB+ on our platform. no complains works great. Make sure you are doing everything right! Are you using predefined statements ? *SQLITE 3.7.3 Transactions Pre made statements Apply these settings (right after you create the DB) PRAGMA main.page_size = 4096; PRAGMA main....

Recently tested with dbs in the 160GB range, works great as well. — Snazzer Jul 13 '11 at 21:43

so, I guess as long as you don't really need high insert speed

CBenni

yeah, I am never gonna reach that size

as I said, a very loose upper end is 10 gigs

the longer it runs, the slower the database grows

because I cap the amount of data stored per user at 150 lines, 256 char max (I think, thats what IRC does)

but yeah, as of now, I have data from ~100k users in the database

There are only roughly 10 mil users on the network in total

should be fine :>

Bob

@CBenni You can always prune older users :P

CBenni

perhaps

I doubt that will be necessary, but indeed, I could purge entries that havent been changed in over a year or so

Does SQL (or more specifically, SQLite/PGSQL) store access times?

if not, I think I will have to change things about my database xD

Bob

@CBenni I don't think so.

0

A: Is there an easy way to add a last modified timestamp while using ORMLite and Android?

You could create a trigger that updates your modificatoinDate each time an insert and update occurs in sqlite. example: db.execSQL("create trigger updateModDate " + "after insert on MY_TABLE for each row begin " + "update MY_TABLE set modificationDate = date('now') where id = NEW.id " +...

also, you probably want last modified over last accessed

otherwise it'd have to write something on every read

Oliver Salzburg

13:09

Have i voted up you cause I am using app lot of previous user were telling me to vote up there answer and I have pressed tick sign have i voted up your answer — user55486 25 mins ago

Wow

allquixotic

@OliverSalzburg wow indeed -- I think "I am using app" means he's on the mobile app, and the "tick sign" must mean the checkbox... I'm pretty good at translating these things

do you speak Internetese? :P

no i do not speak internetese but you should really consider not using any punctuation or capitalization it makes your sentences much easier to read for native internetese speakers

Oliver Salzburg

13:29

@allquixotic The best part is, he didn't upvote

allquixotic

@OliverSalzburg our users shouldn't really be telling newbies to "upvote" their answers though, should they??

Ash

Anybody here uses demonoid ?

Oliver Salzburg

@allquixotic It was migrated here

allquixotic

@Ash you mean illegaloid? no.

Bob

13:56

...

I'm an idiot.

My phone case arrived in the mail today. Except I accidentally ordered cases for the S4 mini

allquixotic

@Bob -________-

RETURN!

Bob

@allquixotic $1

not even worth the postage

allquixotic

-_-

Bob

soooo

apparently when you search for blotting paper, it's all cosmetics-related

Oliver Salzburg

0

Q: Monitor black screen only at starting windows?

I am having a problem with my Asus monitor. The problem is, is that when I start up my computer, the display goes on and I see the 'starting up windows' screen. After that, the screen SOMETIMES goes completely black and I can hear the log in screen sound through my headphones. The only way to fix...

For real?

He's bringing blackscreen back?

Bob

14:09

@OliverSalzburg The mental image is hilarious.

@OliverSalzburg: blackscreen is gone! A good day's work! :D ... I wonder what new questions there are? Hmm... black... screen... why does that sound familiar? Wait... OH FOR FUCK'S SAKE

3

Boris_yo

How come I can't send email through Gmail through secured port 465 if it yesterday worked for me?

...using K9 Mail

allquixotic

@Boris_yo ISP blocking? idk, wireshark it

rodling

14:38

quick question, how do I access a newly attached volume to Linux type instance? I went to /dev but sfd folder is visible with ls but not accessible

allquixotic

@rodling "Linux type instance"? are you running Linux as a virtual machine guest? why are you looking for "sfd"? what distribution and version of Linux are you running?

much more info needed

rodling

@allquixotic I have Amazon Linux, one of those EC2 instance on AWS. Why I am looking for sfd, frankly not to sure. I am trying to recover files from a volume which I detached from a failed instance by attaching it to a fresh one. Had a kernel error

allquixotic

@rodling oh, you mean an EBS volume

this is a googlable problem. I googled "amazon linux mount ebs volume". first two hits: docs.aws.amazon.com/AWSEC2/latest/UserGuide/… and docs.aws.amazon.com/AWSEC2/latest/UserGuide/…

This is a solved problem; Amazon Linux even has built-in tools to help you know which block devices are available. Please work on improving your google-fu.

rodling

clearly googled wrong things initially

thanks!

allquixotic

still no idea where you got "sfd" from :P

rodling

14:50

sorry, sdf

found it somewhere in documentation

your googling is a lot more productive than mine haha

allquixotic

I get that a lot.

"sdf" is just an arbitrary name assigned to the 6th SATA/SAS/SCSI drive to be initialized by the Linux kernel during boot-up. It's sda, sdb, sdc, sdd, sde, sdf, etc. for SATA devices

but since EBS volumes aren't using the SATA subsystem, Amazon uses their own proprietary block device nomenclature.

Journeyman Geek

@allquixotic: pata drives are SD as well

allquixotic

@JourneymanGeek depends on the version of the Linux kernel (or maybe it's udev). old Linux (like RHEL5 and older) would mount PATA under /dev/hd*.

until they made PATA a special case of the generalized ATA subsystem

Journeyman Geek

yup

but that was aaaaages ago

allquixotic

PATA is pretty dead at this point, so there's little point in even discussing it unless you're dealing with ancient hardware or ancient software

of which Amazon Linux is neither :P

I guess Amazon didn't want to virtualize their EBS volumes through the ATA subsystem due to the overhead... whatever custom block device stack they came up with is probably significantly faster, and optimized for the network backend of EBS

Journeyman Geek

15:06

;p

I don't think I have any systems that run ATA still

allquixotic

EBS is basically a local (nearby) high-throughput SAN

or maybe NAS, hard to know the implementation details

Amazon is pretty tight-lipped about the proprietary bits of their EC2 and S3 services

Journeyman Geek

@allquixotic: wouldn't be surprised if it was some virtualised storage device off off the shelf hardware

allquixotic

@JourneymanGeek the virtualization layer isn't COTS, to be sure, but the backend may be

Journeyman Geek

@Bob: I found one more platinum riviere ;p

allquixotic

it's definitely something that can be accessed at the block layer though -- most likely disk images on a filesystem

Journeyman Geek

15:09

I'm wondering if its even that.

allquixotic

one way they could do it is have a bunch of disk image files on a large RAID array on the EBS server, and expose each of those disk images over iSCSI

Journeyman Geek

I wouldn't be surprised if they used block level dedup for example

ewww

allquixotic

I don't think they are physically doing partitions or anything on physical disks when they break off an EBS for you

Journeyman Geek

actually no. I need to set up iscsi when I get my storage box 2.0 set up eventually ;p

allquixotic

that would be too inflexible

most likely it's just dynamically growing/shrinking disk images on a large filesystem

although I guess LVM (or something similar) would be flexible enough for them to use that instead of disk images in a FS

physical -> RAID -> LVM -> each LVM logical volume is an EBS volume? dunno

either way, they need a low overhead, efficient network transport for block-level access

iSCSI does that reasonably well

also I'm pretty sure 100% of Amazon's new instance storage and EBS storage is on SSDs now

their older stuff (if you have a very old instance from a previous generation) may be on HDDs

Journeyman Geek

15:17

@Ash I thought that was quite dead

rodling

15:41

@allquixotic hey, so continuing on that issue of mounting and nomeclature of xvdf and etc. I am trying to mount as per guide and getting an error
`mount: special device xvdf does not exist`
it is listed in `lsblk` and etc

allquixotic

15:51

@rodling if it's listed in lsblk you should be able to mount it; but what exact path are you using in the mount command?

if you just try to mount xvdf (assuming you're not in the /dev directory), you will get an error, because the file ./xvdf (in the current directory, again, assuming the current dir is not /dev) does not exist

check if /dev/xvdf exists using the file command, and make sure to always use absolute paths everywhere, never use relative paths unless you really know what you're doing

rodling

nvmmm i was an idiot haha

allquixotic

PEBKAC

rodling

wrong directory for one of the operation

ya sometimes i just need to think outloud :( haha

allquixotic

I have a coworker exactly like that.

he has a question every 5-10 minutes... 98% of them, if he'd spend just a minute or two thinking about it, he'd be able to resolve by himself

0

Q: Typo in reputation recalc error message

Now that the reputation recalc feature has been removed, the "Trigger Reputation Recalc" button is gone from http://superuser.com/reputation, and attempts to use the original URL to get a recalc (http://superuser.com/reputation?recalc=true) results in the following error message: Reputation r...

support bug reputation rep-recalc

really?

Canadian Luke

16:06

thedailywtf.com/Articles/Pipe-Up.aspx

2

Seth

17:41

0

Q: Hard Drive Detection Problem While dual booting Ubuntu with Windows 8

I have installed Windows 8 on my Laptop and i want to dual boot it with Ubuntu. However since my Hard Disk is Dynamic , Ubuntu cannot identify it. I was wondering how to convert Dynamic back to Basic since all procedures described on windows support are for drives that does not have OS installed...

installation boot dual-boot grub2 windows

He wants to convert his dynamic disk to a basic one with an OS installed on it..

Is that even possible?

allquixotic

@Seth converting a dynamic disk to a basic disk without reinstalling sounds... challenging, at the least.

the dynamic disk format of Windows 8 is basically a Microsoft-specific variant of Software RAID

Seth

That's what I figured.

0

Q: Is is possible to rename PowerPoint color schemes? e.g.: rename ACCENT 1

Is it possible to rename the colors of a color scheme in PowerPoint 2010? I have this client that wants different names on the colors, not Accent 1, Accent 2, etc. Thanks!

microsoft-powerpoint-2010 color-theme

lol.

Anonymous

when was Firefox 28 released?

Seth

a ~~long time ago~~ several weeks ago?

Around Marh 18 is would appear:

in Ask Ubuntu General Room, Mar 18 at 20:55, by Seth

yay, firefox update. One version closer to a new ui.

At least, that's when the update arrived on my machine.

Anonymous

@Seth I'm talking about the main channel anyway not aurora nor nightly

Seth

17:51

@PatoSáinz Yeah I know.

Anonymous

> First offered to Release channel users on March 18, 2014

Seth

I'm running FF 30 on Aurora.

Anonymous

why did it take that much to get to my machine

Seth

Does Firefox install updates automatically? I don't think it does.

Anonymous

it downloads them

Anonymous

17:52

and then applies them until restart

allquixotic

@Seth the Firefox 29 Beta is quite stable (I'd almost venture to say rock-solid, except it has some rendering bugs on AMD Catalyst on Windows 8.1 at home)

@PatoSáinz it may only check the servers periodically, not every time you start FF

Seth

Indeed. I've never really had any problems with Firefox.

allquixotic

I really love the new UI redesign; it's incredibly close to Chrome while also retaining the flexibility and such that I expect from Firefox

saves vertical space, which is super valuable on monitors with 1080 and fewer vertical pixels (which is most monitors these days)

the other thing I notice about Firefox of late is that its performance all around (rendering perf, JS perf, multi-tab perf, etc) is basically on-par with Chrome, yet its memory usage is way less

I was a huge advocate of Chrome in its early days, but the advantages it had are gone, and it's kind of annoying in other ways that FF isn't

I worry that the full multi-process model coming to FF soon is going to bloat its memory usage unnecessarily, without really enhancing security (plugins are already sandboxed; the worst offender is already out-of-process) -- hopefully Firefox 29 will be an ESR, and I'll stick with it for a looong time

Boris_yo

18:47

@allquixotic Wireshark? wat

allquixotic

19:16

!!tell 14580418 bababababat

ChatBot John Cavil

allquixotic

wireshark.org‎

Michael DeMutis