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Old 15th July 2011
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Default how to remove boot sector viruses?

You right I did not say.

Well I was thinking that I could take out the drive, mount it on a USB cradle and read it with a fresh install of Windows to get the data out. How can I do this with open BSD? Is that possible? Perhaps is something that is reserved OBSD Gurus.

Thank you for your response.
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Old 15th July 2011
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Quote:
How can I do this with open BSD?
The ramdisk kernel (bsd.rd) functions without mounting any physical drives. This is why it's called the "ramdisk kernel". Using it, an admin can reinstall or upgrade, including an upgrade-in-place of the installed system, which replaces boot blocks, kernels, and userland libraries and executables (/bin, /sbin, /usr/bin, /usr/lib, /usr/sbin, /usr/libexec, and I'm sure a few other structures I've forgotten).

An admin can also use the ramdisk kernel to restore a complete system from backup, assuming of course, that the admin has invested the time to learn how to do so. Learning how restore a complete system to a "bare" computer should be at the top of your priority list, if you have one. HINT: If you don't have a spare computer, virtual machines are an easy way to practice and learn. You may find the qemu package helpful, if you want to run a virtual machine with OpenBSD as the host.

Obviously, you could boot the installed bsd.rd kernel, or, boot the ramdisk kernel from standard installation media: diskette, cd, or network.
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Old 15th July 2011
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Thanks again jggimi,

This is very interesting and you are right I should learn to do this. As you can probably surmise, I am at the bottom of the OBSD logarithmic curve. I really appreciate your constructive comments and will take them to heart.

I learn something new every time I log into this great forum and it's members.

Again thank you.
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Old 15th July 2011
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When you find you have questions about backing up and restoring, please start a new thread...if Ocicat hasn't split this off to another thread by then.

Some things for you to think about, as you wind your way to self-sufficiency...

Where would you go first to find out about backing up, and restoring? And then where would you look?

Why would jggimi recommend restoring /etc or /var before any other partition? What's in there that its critical to restoring a system? (Yes, I would make that recommendation.)

The ramdisk kernel has restore(8) included, but it will not run on the ramdisk kernel until you provision something. You will get an error message telling you something is missing. You should try this, get the error message, and see if you can figure out what is needed, and what to do.

How do you install boot blocks on your architecture? Why would you need to know how? Where would you go to find out what to do?
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Old 15th July 2011
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Wow!

I think jggimi recommendation is very sound. From what I know there are very important files in etc, network, pf, etc. As for var I know logs and message files.
I'll continue reading and trying climb the curve.


Thanks jggimi!
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Old 15th July 2011
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Quote:
Originally Posted by jggimi View Post
The ramdisk kernel (bsd.rd) functions without mounting any physical drives. This is why it's called the "ramdisk kernel". Using it, an admin can reinstall or upgrade, including an upgrade-in-place of the installed system, which replaces boot blocks, kernels, and userland libraries and executables (/bin, /sbin, /usr/bin, /usr/lib, /usr/sbin, /usr/libexec, and I'm sure a few other structures I've forgotten).
Also of note is /usr/mdec/mbr which is a copy of the master boot record constructed at installation. If you have concerns about the presence of boot sector infection, you can always diff(1) the boot sector against this file.

CyberJet, you will find useful information in the boot_i386(8) manpage, & Section 14.7 of the FAQ.

Last edited by ocicat; 16th July 2011 at 12:27 AM.
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Old 15th July 2011
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This thread was forked from its parent:

http://www.daemonforums.org/showthread.php?t=6121

...due to digressing into OpenBSD-specific questions.

Please, if threads happen to invoke questions which are not in the same direction as the tone set by the thread's originator, start a new thread.

Most of the activity seen on this site is members searching old threads. Whether they take advantage of vBulletin's search facility or search manually ("I remember something was asked about this in this subforum some time ago, so I'll just read through the thread titles until I find it..."), please keep discussions to:
One thread, one topic
It will help the next guy.
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Old 15th July 2011
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Quote:
Originally Posted by CyberJet View Post
From what I know there are very important files in etc, network, pf, etc. As for var I know logs and message files.
No, think about what you would need to have if you were starting with empty hard drives.
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Thanks ocicat,

Sorry for the extra work. I was reading Sec 14- Disk Setup when I saw your post, thanks for the specifics.

I will comply! One thread, one topic.

Thanks again
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