[Freeipa-devel] Replication Topology design feedback

[Oleg Fayans]

Hi Ludwig,

I have a question. What is the proper way of removing ipa replica from
the server that is replication-topology-aware? Standard way
`ipa-replica-manage del` does not work anymore, since the topology is
controlled by the plugin, but I was unable to remove it using
topology-aware tools as well. Here is the transcript of my session:
http://pastebin.test.redhat.com/281213

Thanks in advance!


On 05/04/2015 04:46 PM, Martin Kosek wrote:
> Thanks for answers.
>
> BTW, for future, I think Oleg that it would be useful to ask this questions on
> freeipa-devel directly as it may be helpful to other developers and we would
> have it archived for other uses.
>
> On 05/04/2015 04:20 PM, Ludwig Krispenz wrote:
>> On 04/30/2015 03:22 PM, Oleg Fayans wrote:
>>> Hi Ludwig,
>>>
>>> While getting myself familiar with Replication Topology Plugin design
>>> page I've found a number of places that need some clarifications.
>>>
>>> 1.
>>>> Check at startup.
>>>> When the directory server starts, the plugin init and start functions
>>> are executed, they will read the domain level
>>>> attribute and act accordingly
>>> Could you describe how exactly should the plugin work depending on the
>>> domain level revealed.
>> there are only two scenarios:
>> 1] domain_level < plugin_level:
>> the plugin does almost nothing, reading its config and waiting for a dom level
>> increase
>> 2] doamin_level >= plugin_level:
>> the plugin controls topology for managed servers, rejecting direct mods of
>> replication agreements, transforming adding/deleting/modification of segments
>> into corresponding actions on replication agreements
>>> 2.
>>>> Check for modify operation
>>>> If an admin or tool changes the domain level the plugin detects this
>>> change and performs initialization tasks if the
>>>> domain level is greater than the plugin version
>>> The same here: what exactly happens after the domain level has changed.
>> if the domain level raises, so that teh plugin becomes active, this will happen
>> on all servers since domain level is replicated.
>> the plugin will read all the exisußing info inthe shared tree, read all
>> replication configuration and match them creating missing data in both areas:
>> cn=config and shared tree
>>> 3. Regarding the startup delay. How can I make sure the plugin has started?
>>> As far as I understood the Topology plugin needs to be started only
>>> after all other plugins are started to prevent it from making a tree
>>> changes before it is able to be replicated. The question is: how do I
>>> check whether all other plugins are already started?
>> the plugin should be started when the server starts, it will expose this in the
>> root dse and you can search for it, I just updated teh design page with an example
>>> 4. Shared configuration layout
>>> It is written there, that the replication topology information can be
>>> configured to be stored in the custom place of the tree. How do we do that?
>> The configuration is in the plugin conf in cn=config. At the moment it is
>> populated when a DS instance is created.
>>
>>> Most probably I''ll have some more questions once I have the branch
>>> installed.
>>>
>>> Thank you!
>>>

-- 
Oleg Fayans
Quality Engineer
FreeIPA team
RedHat.