RHN Update

[Michael Schwendt]

On Tue, 15 Feb 2005 21:41:02 -0600, Brad Carpenter wrote:

> OK, basic question here, we are running RHEL3 AS using it for ISP functions,
> last time I connected to RHN it wanted to download a caching-nameserver,
> which I did, which took over and made our secondary DNS server "fall off the
> map". 
> 
> We recovered fairly easily, albeit very nervously, and wish NOT to run into
> such problem again.  
> 
> Question is "Are there updates that we should ignore on a system like this?"
> And if so, how does one go about picking and choosing what to skip and what
> to keep?
> 
> I see posts that say "update everything" all the time, is this the way it is
> expected to work?

Yes.  Precisely, get the security/bug-fix updates for all packages you
have installed already. Be careful when adding new packages to your
installation which don't replace existing old packages.

The caching-nameserver package you installed was not present on your
system before and hence overwrote existing config files with its new
contents. Probably just /etc/named.conf and local zone files in
/var/named.

Once installed, the config files within RPM packages are protected in two
ways against being overwritten during updates. Depending on how an RPM
package is configured, an update either creates *.rpmsave backup files of
existing config files or stores its new config files in *.rpmnew where you
can review them before copying any new default settings to your existing
config files.

Where you can choose a custom name for config files (e.g. zone files in in
/var/named) choose a good namespace that's unlikely to be used by RPM
packages.