Terracotta Discussion Forums (LEGACY READ-ONLY ARCHIVE)

Hi,

I'd like to know if Terracotta DSO is suited for teh following usage:

I have serveral machines distributed in different datacenters. I need to replicate some content to each of them.

I could use Terracota DSO but I wonder what would happen when the network connection quality degrades (starts loosing some tcp packet) or when a machine is temporarly unreacheable (for a few minutes).

Will the changes be accumulated and replicated when the network connection is back or the cluster will reject any changes made to it if it cannot reach all the host?

Hi James,
Depending on how far away the data centers are geographically located, we have multiple WAN deployment strategies. We would be happy to discuss your particular use case one on one.

If the cross data center latency is not an issue (i.e. if the data centers are close enough) the Terracotta Server in one data center can serve JVMs across multiple data centers.

Another deployment scenario would be to deploy Terracotta across multiple data centers by hosting a separate Terracotta Server in each data center (so each data center is a separate cluster) and load balancing the requests to a particular data center based on locality of reference (sticky to a data center).

To answer your specific question, if a JVM network call to the Terracotta Server fails the changes would be accumulated and replicated whenever the JVM can reach the Terracotta server again. If the socket connection itself breaks, the Terracotta Server would reject that particular JVM only (the rest of the cluster will not be disturbed) till the JVM is recycled. This ensures cluster coherency is not compromised.

Our product roadmap includes more features to fecilitate WAN based cross data center replication so watch this space for our future releases.

Regards,
Kunal Bhasin - kbhasin@terracottatech.com.

You might also look into this forum message: http://forums.terracotta.org/forums/posts/list/91.page where I asked a similar question. There is a link to an open Jira issue for adding async WAN support to Terracotta: https://jira.terracotta.org/jira/browse/CDV-28
I would encourage you to vote for this issue if you are so inclined.

I wanted to point out that you must be logged in to be able to vote on this issue at the JIRA link posted by anodos above.

Regards,
Kunal Bhasin.