Difference between rpm -i and rpm -U ?

[Paul Howarth]

Rex Dieter wrote:
> Dan Thurman wrote:
> 
>> What is the difference between rpm -i and rpm -U ?
>>
>> If I have a bunch of rpm files and use -i, will it remove
>> previous versions of packages or will it retain older packages
>> and install the newer package on top?
> 
> The latter.
> 
>> I assume -U looks for older packages, removes it if found,
>> and then installs the newer package?
> 
> Yep.  In 99% of cases, -U is the way to go, unless you specifically want 
> multiple versions installed (like kernels, for instance).

Actually I think the behaviour of -U is:

* install the new package
* remove the old one (i.e. any files in the old package that aren't in 
the new one)

This is why you sometimes end up with multiple versions of packages 
appearing in the rpm database when an rpm transaction fails part way 
through (e.g. due to an error in a post-install script).

Paul.