Omnimaga

General Discussion => Technology and Development => Computer Usage and Setup Help => Topic started by: pianoman on May 31, 2011, 10:22:26 pm

Title: Live CD help
Post by: pianoman on May 31, 2011, 10:22:26 pm
Hi, everyone!
I was just thinking about trying out Linux for the first time.
I was just wondering how you boot an OS from a live cd?
Also, how do you make one?
Thanks!
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 10:25:37 pm
To make a live Cd you just take an image burning software and burn an iso to a disk. To load that iso(run the liveCD) you need to choose the boot device through bios. It should be either F10 or F12(more common). try both. Turn off your comp and turn it back on while button mashing one of those. If it boot regularly you need to try the other one. If it worked it should go to a menu with the different bot devices. Choose CD-Rom and let it load. It should load straight into the LiveCD at that point. If you have any problems I'd e glad to help you
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 10:31:52 pm
One more thing: what exactly is a RAM disk? I read about it on Wikipedia, but it wasn't too clear. Is it a permanent thing, or does it go away when you reboot?
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 10:32:25 pm
Let me google it then I'll tell you lol

EDIT:Its a super fast version of an SSD. Lot more expensive also
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 10:32:43 pm
Ok thanks :P
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 10:35:11 pm
Yeah its basically an SSD with lots of steroids. Ti is faster and more expensive. ITs RAM that the computer is using liek it was an SSD with a speed bost
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 10:37:35 pm
So it is only around for the time that you are using the live cd? It doesn't take away from the RAM when using the regular OS?
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 10:41:08 pm
No RAM disks are very different. You won't be using any of those unless your crazy or have lots of money to spend on super fast memory. The OS is stored in RAM and run from there yes. It does use the comps RAM
Title: Re: Live CD help
Post by: alberthrocks on May 31, 2011, 10:49:38 pm
No no no, ramdisks are NOT ram disks :P

In linux Live CDs (or DVDs, for that matter), they usually load the filesystem into the RAM so that it's faster to use, and will need the CD less. You usually can find this filesystem image as initrd on the CD. (Typically, they name it something else to conceal that name :P) Note that although you may have a ramdisk loaded, the CD is still being used, and you won't be able to eject it. Ramdisks are typically tiny little guys that spark the start of the system. They can range from 1 MB to 30 MB in size, but there's no "limit" persay.

Note that ramdisk is NOT related to general OS behavior, which is loading programs into memory and caching them for faster load times. That's why when you open something in LiveCD, it loads it from the CD, and if you close and reopen that same app, it will load pretty fast using little or no CD at all.

Hope this clarifies things! :D
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 10:53:31 pm
Ok, but what I'm confused about is if this bit of the ram that is being allocated for the ramdisk will be accesible by the OS installed on the computer after you reboot.
Do you know about that?
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 10:57:53 pm
It deends on how long you wait before switching back. If you leave your comp off for an hour or two it should all be gone by the time you turn on your OS. if you just restart into your regular Os then yes it might still be there
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 10:59:50 pm
But eventually, it will go away?
Sorry if I sound hyper-anxious, but I really don't want to screw up my computer when my parents are considering actually getting me a new one.
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 11:02:46 pm
There is really no chance of you messing up your comp from a liveCd unless you go crazy with the terminal or gparted
Title: Re: Live CD help
Post by: pianoman on May 31, 2011, 11:03:38 pm
Lol ok.
Thank you very much!
[:)]^9001
Title: Re: Live CD help
Post by: alberthrocks on May 31, 2011, 11:03:49 pm
Oh no worries, LiveCD ramdisks go poof as soon as you power down your computer or reboot it. :)
If you want a guarantee that it is gone, simply boot into your regular OS. That will typically overwrite any memory of... that LiveCD memory. :P
Title: Re: Live CD help
Post by: ruler501 on May 31, 2011, 11:05:46 pm
Don't play with things that warn about potential memory loss and you;ll be fine(like partitioning. If you don't understand get help so you don't break anything). LiveCD themselves are erfectly safe the users on the other hand are not always the safest in what they do. To sum it up be careful and nothing bad will happen
Title: Re: Live CD help
Post by: jnesselr on May 31, 2011, 11:05:52 pm
That is one good thing about a live CD, mind you.  It really has no effect on your regular hard drive.  Just don't mess with anything.  I wouldn't even mount it, if I were you, if you don't know what you are doing.