bryce, did you resolve this? i'm interested in the outcome. when you write does it help to use CL = LOCAL_QUORUM?
On Mon, Oct 29, 2012 at 12:52 AM, aaron morton <aa...@thelastpickle.com> wrote: > Outbound messages for other DC's are grouped and a single instance is sent > to a single node in the remote DC. The remote node then forwards the message > on to the other recipients in it's DC. All remote DC nodes will however > reply directly to the coordinator. > > Normally this isn’t an issue for us, but at times we are writing > approximately 1MB a sec of data, and seeing a corresponding 3MB of traffic > across the WAN to all the Cassandra DR servers. > > Can you break the traffic down by port and direction ? > > Cheers > > > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 28/10/2012, at 12:18 PM, Bryce Godfrey <bryce.godf...@azaleos.com> wrote: > > Network topology with the topology file filled out is already the > configuration we are using. > > From: sankalp kohli [mailto:kohlisank...@gmail.com] > Sent: Thursday, October 25, 2012 11:55 AM > To: user@cassandra.apache.org > Subject: Re: High bandwidth usage between datacenters for cluster > > Use placement_strategy = > 'org.apache.cassandra.locator.NetworkTopologyStrategy' and also fill the > topology.properties file. This will tell cassandra that you have two DCs. > You can verify that by looking at output of the ring command. > > If you DCs are setup properly, only one request will go over WAN. Though the > responses from all nodes in other DC will go over WAN. > > On Thu, Oct 25, 2012 at 10:44 AM, Bryce Godfrey <bryce.godf...@azaleos.com> > wrote: > > We have a 5 node cluster, with a matching 5 nodes for DR in another data > center. With a replication factor of 3, does the node I send a write too > attempt to send it to the 3 servers in the DR also? Or does it send it to 1 > and let it replicate locally in the DR environment to save bandwidth across > the WAN? > Normally this isn’t an issue for us, but at times we are writing > approximately 1MB a sec of data, and seeing a corresponding 3MB of traffic > across the WAN to all the Cassandra DR servers. > > If my assumptions are right, is this configurable somehow for writing to one > node and letting it do local replication? We are on 1.1.5 > > Thanks > >
