Hosts within a cluster should have low-latency communications: gigabit ethernet or better. Ideally they should all be on the same switch and/or VLAN, with no router hops between hosts. If you try to set up a cluster across a WAN link you are likely to see poor performance and poor reliability. You might be trying to handle high availability (HA) and disaster recovery (DR) with a single cluster: that would be a mistake.
For high availability, use a single cluster with low-latency communications. Configure forest replication and host failover to provide the desired degree of protection against host failures. The docs at http://docs.marklogic.com/guide/cluster/failover talk about this as "local-disk failover". For disaster recovery - scenarios where an entire data center goes offline - use database replication to a different cluster. This can use higher-latency communications, such as a WAN link. The docs at http://docs.marklogic.com/guide/database-replication describe this. The DR replica cluster can also implement local-disk failover to provide its own HA. -- Mike On 28 Oct 2013, at 06:41 , Arindam3 B <[email protected]> wrote: > Hi, > > I had a query regarding the E-Node and D-Node setup in Marklogic. > > In a distributed environment, if I plan to keep the Enodes and DNodes > separately in different physical locations over the LAN or WAN (across > geographies), what is the potential risk? > How does failover work in that scenario? > I have read that ENodes and DNodes communicate through XQDP protocol, so in > this case will there be performance issues? > > Does Marklogic recommend having ENode and DNode cluster in the same physical > box? > If so, then across the network if we have a set of E-D-Nodes, how is the > network latency reduced while synching the data during replication? > > If you can provide me with some information about XQDP protocol it would be > great!! > > Thanks & Regards > Arindam Bose > =====-----=====-----===== > Notice: The information contained in this e-mail > message and/or attachments to it may contain > confidential or privileged information. If you are > not the intended recipient, any dissemination, use, > review, distribution, printing or copying of the > information contained in this e-mail message > and/or attachments to it are strictly prohibited. If > you have received this communication in error, > please notify us by reply e-mail or telephone and > immediately and permanently delete the message > and any attachments. Thank you > > > _______________________________________________ > General mailing list > [email protected] > http://developer.marklogic.com/mailman/listinfo/general _______________________________________________ General mailing list [email protected] http://developer.marklogic.com/mailman/listinfo/general
