[CentOS] rpm --freshen issue (was: Re: Caught between a Red Hat and a CentOS)

ken gebser at mousecar.com
Wed Oct 21 10:12:14 UTC 2009


On 10/20/2009 12:15 PM Benjamin Franz wrote:
> ken wrote:
>> Okay, here's one. Maybe someone here can figure it out.
>> Upgrading from 4.5 to 4.5.  From a 4.6 ISO I copied all the RPMs into a
>> directory... let's call it c:/install :).   Now the oracle dba has
>> strict parameters on what versions can be installed and which can't.
>> The rpms in c:/install meet those requirements.  In addition, since this
>> is a production machine, it can be down at most for one day.  So all I
>> want to do is upgrade what's currently on the system.  Moreover, if
>> something horks, I want two chances to back out (the second being asking
>> the backup guy to put the system back to yesterday).  The command to do
>> this would be
>>
>> rpm --freshen --repackage *
>>
>> run in that crazy c:/install directory (or what the redhat guy called, a
>> "folder").  This command runs fine for one file which has no
>> dependencies (i.e., change '*' to a specific rpm).  It also upgrades
>> three or four co-dependent rpms if they're narrowly specified.  But if
>> the file/rpm spec is '*', rpm complains about two missing dependencies
>> and stops.
>>
>> Yeah, this directory contains 1507 rpms (IIRC)... which is a lot, but it
>> should still work.  This is Linux, after all.  And there's plenty enough
>> memory and cpu to handle it.
>>   
> 
> Running
> 
> rpm --freshen --repackage * 
> 
> for 1500+ rpms  probably exceeds the maximum character length for some 
> part of the system after expansion of the '*'  by the shell.

That was my first suspicion too.  The redhat tech didn't bring that up
though.  (That doesn't mean I'm going to ignore that as a possible
workaround; the original conversation here was about tech support per
se.  Of course I'm still seeking ways to do the job.  And so thanks for
the suggestion.)

I, too, recall reading some years back about a bash line length limit.
Back then, a long time ago, it was 2048 characters.  So I ran "echo *"
in that same install/ directory and the output included all 1507 files.
 So the problem's not with a bash command line length limit, but still
pointing to the "rpm" command.



> 
> Try breaking it up into smaller chunks (say two or three hundred at a 
> time). You can match subsets of the files using shell expansions like
> 
> rpm --freshen --repackage [a-g]*
> 
> and tweak the line for any dependency complaints manually.

This solution occurred to me also.  And right now it's a top contender
(along with another I'll mention shortly).  If the job environment were
different, I'd go with it.  But my boss is making me jump through a lot
of hoops for this project.  This upgrade from v.4.5 to v.4.6 needs to
happen in a single, specified day *and* my boss needs to know how long
it will take me to accomplish, this so the Oracle dba knows when he can
start to on what he's got to do for this upgrade.  And I have at most
fifteen hours (i.e., two working days) to come up with this fool-proof
plan.  Plus, I don't have a test box to try things out on.  But I've had
to do trickier stuff than this in the past with not dissimilar time
constraints, so though I should be taking extra boxers to work, I'm not
(yet).

So what I was thinking of doing is scripting the solution you suggest
above.  But then, if I'm going to script something, I might as well
write a script that will take on the entire task wholistically.  I mean
something like this:

ls -1 install/ > what-to-upgrade.list  # create package list
while read package | {upgrade package}  #just quasi-code here. Loop.
if {there's nothing to upgrade}
  remove pkg from what-to-upgrade.list
  log this
  continue
fi
if {there are dependencies}
then for {each dependency} {upgrade package}  # yep, recursion
fi
else [upgrade package}         # simplest case, just upgrade one pkg

The {upgrade package} function would be fairly simple (I think):
- Find the correct package in the install/ directory (containing the
RPMs for v.4.6).
- Upgrade the 4.5 package with that correct 4.6 package.
- Confirm that the 4.6 is installed.
- Remove that package name from what-to-upgrade.list
- Log that this package has been upgraded.

I already see some bogus stuff here, but I'm writing this on the fly.
Point is, it seems do-able, and probably within the time constraints.
And then, what are the alternatives?

One, suggested by the redhat tech (about whom there's more news...
later), is to use up2date.  I read the manpage on it and it's pretty
vague.  I'm sure I have, but I don't recall using it before, so I can't
fill in the details which the manpage lacks.  Lastly, I don't see a way
to test up2date to see if it will work within my (dba's) specific
parameters.


Benjamin, thanks for your constructive response.  Any further such (from
you or anyone else) will be much appreciated.

Best,
ken

> 
> Alternatively, use 'createrepo' to create a Yum repository of the RPMs 
> and use yum to handle it for you.
> 


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