jackrabbit-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jeroen Reijn <j.re...@onehippo.com>
Subject Re: Add new nodes to a cluster
Date Tue, 19 Apr 2011 11:46:31 GMT
On Mon, Apr 18, 2011 at 3:18 PM, Christian Stocker <
christian.stocker@liip.ch> wrote:

>
>
> On 18.04.11 11:04, Jeroen Reijn wrote:
> > I'm also not 100% sure, but I can second Alex his answer.
> >>From what I've seen the new cluster node will start from the persisted
> data
> > and will continue from there on with using the journal.
>
> The question is then, how does the new cluster node know on which
> position he should start? Or do we "just" have to make sure, that
> nothing writes between the start of the new node and "when it's ready".
> How do we know it's ready then?
>

If you're using a database I know that there is a table in which Jackrabbit
stores the global revision, which is the latest revision. All the nodes in
the cluster will work towards that revision based on the repository journal.
My best bet would be that when a new node in the cluster starts, it starts
from this global revision.

Next to the global_revision table, there is also a local_revision table that
contains the current revision for each node in the cluster.



>
> But thanks for the input so far
>
> christian
>
> >
> > Jeroen
> >
> > On Mon, Apr 18, 2011 at 10:52 AM, Michael Wechner <
> michael.wechner@wyona.com
> >> wrote:
> >
> >> Hi
> >>
> >> I am not sure if you received an answer on this already, but it seems
> >> somebody asked the
> >> same some time ago
> >>
> >> http://web.archiveorange.com/archive/v/L1HBQddB3PYM2Fsde3ZL
> >>
> >> (with one not totally certain answer).
> >>
> >> On the other you might just give it a try and check what it will do.
> >>
> >> I would also be interested in your findings.
> >>
> >> Thanks
> >>
> >> Michael
> >>
> >>
> >> On 4/14/11 11:20 AM, Christian Stocker wrote:
> >>
> >>> Hi
> >>>
> >>> We're currently building a jackrabbit setup with quite some new content
> >>> every day. We also want to use clustering and beeing able to add new
> >>> instances should the need arise. Reading
> >>> http://wiki.apache.org/jackrabbit/Clustering that seems to be not that
> >>> easy (adding a completely new instance) without having to replay the
> >>> whole journal from the beginning (which can take ages, of course).
> >>>
> >>> Is there an easy, recommended way to add new instances without having
> to
> >>> replay the whole journal? In the "Janitor" section, there's the remark
> >>>
> >>> "If the janitor is enabled then you loose the possibility to easily add
> >>> cluster nodes. (It is still possible but takes detailed knowledge of
> >>> Jackrabbit.)"
> >>>
> >>>
> >>> Is this still the case? What "Detailed knowledge" do we need, to just
> >>> "clone" a running instance and add that to the cluster?
> >>>
> >>> (using the janitor would certainly make sense in our use case)
> >>>
> >>> Any hint is very appreciated
> >>>
> >>> christian
> >>>
> >>>
> >>
> >
>
> --
> Liip AG  //  Feldstrasse 133 //  CH-8004 Zurich
> Tel +41 43 500 39 81 // Mobile +41 76 561 88 60
> www.liip.ch // blog.liip.ch // GnuPG 0x0748D5FE
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message