[Freeipa-users] changing the default for changelog trimmimg

[Ludwig Krispenz]

On 07/03/2015 02:28 PM, Petr Spacek wrote:
> On 3.7.2015 14:21, thierry bordaz wrote:
>> On 07/03/2015 02:03 PM, Petr Spacek wrote:
>>> On 3.7.2015 11:45, thierry bordaz wrote:
>>>> On 06/30/2015 03:54 PM, Ludwig Krispenz wrote:
>>>>> Hi,
>>>>>
>>>>> 389-ds allows to configure the max size of the replication changelog either
>>>>> by setting a maximum record number or a maximum age of changes.
>>>>> freeIPA does not use this setting. In the context of ticket
>>>>> https://fedorahosted.org/freeipa/ticket/5086 we are discussing to change the
>>>>> default to
>>>>> enable changelog trimming.
>>>>>
>>>>> Does anyone already use changlog trimming or is there a  scenario where you
>>>>> rely on all changes being available ?
>>>>>
>>>>> Thanks for your feedback,
>>>>> Ludwig
>>>>>
>>>> Hello,
>>>>
>>>>      I think it is reasonable to set nsds5ReplicaPurgeDelay and
>>>>      nsslapd-changelogmaxage to similar value.
>>>>
>>>>      When a replica (master or consumer) is down for some time and is
>>>>      restarted, both attribute express the ability to get the replica in
>>>>      sync with the rest of the topology.
>>>>      It can work (and likely will) if
>>>>      nsds5ReplicaPurgeDelay<nsslapd-changelogmaxage but there are always
>>>>      corner cases that can lead to problem (like entries that diverge).
>>>>
>>>>      Currently purgedelay=7days (default) and changelogmaxage is infinite
>>>>      and changing purgedelay=infinite impacts the size of the entries.
>>> I wonder if these values could/should be controlled by topology plugin. Does
>>> it make sense to have different values on different replicas?
>>>
>> Purgedelay can be different on each replica but it makes sense that the value
>> is the same on all replicas. It is used to remove too old csn and so how far
>> in the past the replication can decide which value is more recent than an
>> other one. With different values of purge delay, a replica can decide to keep
>> one value and an other replica can decide the opposite.
>> Currently purgedelay is identical on all replicas (default value).
> I understand that technically it is possible so the question is more like
> 'does it even make sense'?
no, it doesn't make sense. At least I can't imagine a scenario, where it 
does
> Do we want to support it?
what exactly do you mean by this, you always can as a last method edit 
the dse.ldif, even if you can catch all online mods by a plugin like the 
topo plugin.
do we offer an easy way to configure and modify it, I think: no
does one loose support if changing the default, no
>