Keith Lofstrom wrote:
> There is a program called "prelink" that works with the program loader
> to rewrite the symbol tables in libraries and executables for faster
> loading.  It is turned on by default in Red Hat derived systems like
> Scientific Linux.
> 
> Yikes!
> 
> I do disk-to-disk backups with dirvish/rsync (I like dirvish so much,
> I host www.dirvish.org  ;-)  )  and have started doing file integrity
> monitoring with osiris.  It appears that "prelink" changes the
> binaries and libaries while leaving ctime/mtime at previous values.
> 
> Just like a virus does, so prelink sets off all sorts of alarms.  
> Sorry, I would rather have slow, stable and safe instead of fast
> and fragile, so bye-bye prelink .
> 
> I plan to remove /etc/cron.daily/prelink,  revert my binaries and
> libraries with "prelink -au", then comment out all the "-l" lines
> in /etc/prelink.conf so that the loader doesn't attempt to do it.
> 
> Then I will rebuild my backups, and reinitialize osiris.  
> 
> Any flaws in my thinking?

I'd not be comfortable doing something of that kind because it violates 
how the designers of the distro expect it to work, and any changes they 
make are based on it working "just so."

That said,
08:09 [root@Numbat ~]# rpm -q --whatrequires prelink
no package requires prelink
08:09 [root@Numbat ~]#
so you could probably get away with just removing it.

It would be interesting to benchmark your system with it and without it.


Howerver, /usr can be mounted ro. / should be okay too, one has to make 
arrangements for places such as /tmp, and /var has to be a separate 
filesystem.

If your testing shows prelink is worth having, then you could run it as 
part of your software update process (when you have to mount everything 
rw for a time).






-- 

Cheers
John

-- spambait
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