[vox-tech] Linux file/module security proposal.

[Bill Broadley]

jim wrote:
>    i'm considering rebuilding my machines on a 
> regular basis. in the case of a vital service, 
> it seems a clustered set of servers would permit 
> taking one out and rebuilding it then putting it 
> back in and taking out another, rebuilding, and 
> so on. 
>    rebuilding would be a matter of copying over 
> all executables, probably using the  dd  command. 
>    it would be important to partition the hard 
> drive and load only the kernel, libraries, 
> executables, and config files that were necessary 
> to support the service. 
>    i'd consider removing or renaming or 
> recompiling essential utilities such as ls and 
> grep and ps and vi and so on. 
> 
>    tho'ts? 

What is the advantage?  Seems like a fair bit of work, constantly migrating 
the files you keep vs the ones replace.  It doesn't really add any security, 
if you had a vulnerability before the image you will have one after.  Sure 
backdoor installation would have to happen again.  But you'd have be very 
careful auditing any files you take from the old version of the system.  I'd 
invest the admin time for the reimaging and setting up the infrastructure to 
hardening, backups, or documentation so that if you do get exploited.  It also 
could make patching more complicated.

So I don't see what dd gets you, or did you mean from a partition that's never 
exposed to the internet?  What does the recompiling do for ya?  I guess with a
more detailed explanation I could provide more detailed feedback.