Do not setup cross DC clusters, it's not recommended and ends up providing
more headaches than it is worth.
You are better off replicating your data using either snapshot+restore or
sending it to each individual cluster through your code.
On 12 February 2015 at 11:56, Parag Shah parags@gmail.com wrote:
Hi all,
I am trying to setup async replication with a multi-dc setup. Here ismy scenario:
- I will have 3 nodes in each DC. For now, assume I have only 2 DCs.
- I would like to use async replication, such that it writes
synchronously to the primary shard, but writes to only one node
asynchronously in the remote DC.- I would like to have 2 replicas. So, 3 copies in all.
I have looked at the cluster awareness settings here
http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/modules-cluster.html.
However, I am not sure how it will work in practice, because if I simply
set "async" replication on each indexing request, it may choose to
replicate all 3 copies locally (including the primary) or even worse, 1
copy locally and 2 copies in the remote DC.If I use the dc as the cluster awareness attribute, it will create only 1
copy in the local dc and another one in the remote DC. That won't satisfy
by 3 copies requirement.If I create an additional attribute which is zone like this:
cluster.routing.allocation.awareness.attributes: dc, zone
and divide my DC into zone 1 (1 node?) and zone 2 (2 nodes?) and
vice-versa in the remote DC, I might be able to distribute the load
between zones in a DC and between DCs for the 3rd copy. However, there is
still the possibility that 2 of it's replica shards might be allocated in
the remote DC, which will prevent me from obtaining local (DC) quorums.Can someone shed light on how shard allocation works when you have more
cluster allocation attributes than 1?Also, if there is some known best practice for doing Async Replication
with MultiDC such that local quorums are always possible for reads/writes,
it will be greatly appreciated. In summary, I am looking for 3 copies
including primary. 2 in the local DC and 1 in the remote DC and want to
write synchronously only to the primary shard.Thanks in advance,
Parag--
You received this message because you are subscribed to the Google Groups
"elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an
email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/elasticsearch/8f2a2c8c-4910-487c-9e5e-bfcfb96a235d%40googlegroups.com
https://groups.google.com/d/msgid/elasticsearch/8f2a2c8c-4910-487c-9e5e-bfcfb96a235d%40googlegroups.com?utm_medium=email&utm_source=footer
.
For more options, visit https://groups.google.com/d/optout.
--
You received this message because you are subscribed to the Google Groups "elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAEYi1X9fun9091RLeXZci29dHFHwXs-L8X%3DzEsZ%2BxOerhg9%3DCA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.