[Freeipa-devel] topology management question

[Simo Sorce]

On Wed, 07 Jan 2015 17:11:53 +0100
Ludwig Krispenz <lkrispen at redhat.com> wrote:

> 
> >>>> Now, with some effort this can be resolved, eg
> >>>> if the server is removed, keep it internally as removed server
> >>>> and for segments connecting this server trigger removal of
> >>>> replication agreements or mark a the last segment, when tried to
> >>>> remove, as pending and once the server is removed also remove the
> >>>> corresponding repl agreements
> >>> Why should we "keep it internally" ?
> >>> If you mark the agreements as managed by setting an attribute on
> >>> them, then you will never have any issue recognizing a "managed"
> >>> agreement in cn=config, and you will also immediately find out it
> >>> is "old" as it is not backed by a segment so you will safely
> >>> remove it.
> >> I didn't want to add new flags/fields to the replication agreements
> >> as long as anything can be handled by the data in the shared tree.
> > We have too. I think it is a must or we will find numerous corner
> > cases. Is there a specific reason why you do not want to add flags
> > to replication agreements in cn=config ?
> Simo and I had a discussion on this and had agreed that the "marking"
> of a replication agreement
> as controlled by the plugin could be done by a naming convention on
> the replication agreements.
> They are originally created as "cn=meTo<remote host>,..." and would
> be renamed to something like
> "cn=<local host>-to-<remote host>,....." avoiding to add a new
> attribute to the repl agreement schema.
> 
> Unfortunately this does not work out of the box. I only discovered
> afetr implementing and testing (was not aware of before :-)
> that DS does not implement modrdn operation for internal backends, It 
> just returns unwilling_to_perform.
> And if it will be implemented the replication plugin will have to be 
> changed as well to catch the mordrdn to update the in memory
> objects with the new name (which is used in logging).
> 
> So, if there is no objection, I will go back to the "flag" solution.

What about simply deleting the agreement and adding it back with the
new name ?

This way you avoid having to deal with modrdn.

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York