cache and index backup and restore ?

[Ian Boston <ie...@tfd.co.uk>]

Hi,
Having done a cold backup of a MongoMK instance with a FS Datastore, is
there any advantage in also backing up the local disk copy of the lucene
index (normally in repository/index/** ) and persistent cache file
(repository/cache/**) so that it can be restored on more than one Oak
instance in the cluster..... or do both those subtrees get zapped when the
new instance starts ?

Also, if I tar up everything to restore multiple times, is there anything I
need to edit on disk to make the instances distinct. IIRC there was a
sling.id at one point, but that might have been JR2 rather than Oak.

Best Regards
Ian

Re: cache and index backup and restore ?

[Thomas Mueller <mu...@adobe.com>]

Hi,

Sure, there is a performance advantage (for both the persistent cache and
the Lucene index cache). But how much exactly depends on the use case.

You forgot the "persistent cache" by the way.

When restoring, you need to ensure that the local cache is not newer than
the remote (MongoDB), and from the same "branch" (when copying and
branching MongoDB databases).

> Also, if I tar up everything to restore multiple times, is there
>anything I
need to edit on disk to make the instances distinct.

No, not that I know of.

Regards,
Thomas



On 21/01/16 14:56, "ianboston@gmail.com on behalf of Ian Boston"
<ianboston@gmail.com on behalf of ieb@tfd.co.uk> wrote:

>Hi,
>Having done a cold backup of a MongoMK instance with a FS Datastore, is
>there any advantage in also backing up the local disk copy of the lucene
>index (normally in repository/index/** ) and persistent cache file
>(repository/cache/**) so that it can be restored on more than one Oak
>instance in the cluster..... or do both those subtrees get zapped when the
>new instance starts ?
>
>Also, if I tar up everything to restore multiple times, is there anything
>I
>need to edit on disk to make the instances distinct. IIRC there was a
>sling.id at one point, but that might have been JR2 rather than Oak.
>
>Best Regards
>Ian