This is almost exactly what we do with our riak clusters (as well as actually all our subclusters). It's actually nice for developer because when they need to talk to a network service they just reference 127.0.0.1 and some port, and haproxy gets them to the right place. This also allows an operations team to make network changes without impacting applications (via the use of the haproxy reload).
The only downside is that if your connections are long lived and you restart your riak nodes, all requests will end up on the last node. And if you restart haproxy they will all end up on the first node initially. I sort of wish there was a configuration parameter to haproxy to randomize the start point for the roundrobin so you could keep things a little more balanced across many machines running haproxy. -Anthony On Mon, Jun 25, 2012 at 07:44:05AM -0400, Sean Cribbs wrote: > Another typical setup is to have each client node have its own haproxy, and > when Riak nodes are added or removed (not a common occurrence, mind you), a > configuration management tool like Chef/Puppet/cfengine/etc can adjust the > config and signal the process to reload it (I think it's `kill -HUP`). Then > your client code also only ever needs to connect to localhost, and doesn't > have to have itself reconfigured. > > On Mon, Jun 25, 2012 at 4:40 AM, Samuel Elliott <s...@lenary.co.uk> wrote: > > > On Mon, Jun 25, 2012 at 7:36 AM, Matt Black <matt.bl...@jbadigital.com> > > wrote: > > > Dear list, > > > > > > Does anyone have an opinion on the concept of putting a Riak cluster > > behind > > > a load balancer? > > > > It has been done before. there are various results when searching > > "riak haproxy" in your favourite search engine. > > > > > > > > We wish to be able to automatically add/remove nodes from the cluster, so > > > adding an extra layer at the front is desirable. We should also benefit > > for > > > incoming requests behind shared across all nodes. > > > > > > Can anyone see any drawbacks / problems with doing this? > > > > If your load balancer falls over, what do you do then? Highly > > available may go down the pan. Have more than one would be the obvious > > answer. > > > > What do you do when you want to transparently add more machines to > > your load balancer? > > > > Maybe it might be better to have a list of riak nodes stored in a > > separate registry (I'm thinking something like zookeeper), that your > > application servers can then poll for changes (or even subscribe to > > changes) to the list of servers. > > > > Sam > > > > > > > > Thanks > > > Matt > > > > > > > > > _______________________________________________ > > > riak-users mailing list > > > riak-users@lists.basho.com > > > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com > > > > > > > > > > > -- > > Samuel Elliott > > s...@lenary.co.uk > > http://lenary.co.uk/ > > +44 (0)7891 993 664 > > > > _______________________________________________ > > riak-users mailing list > > riak-users@lists.basho.com > > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com > > > > > > -- > Sean Cribbs <s...@basho.com> > Software Engineer > Basho Technologies, Inc. > http://basho.com/ > _______________________________________________ > riak-users mailing list > riak-users@lists.basho.com > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com -- ------------------------------------------------------------------------ Anthony Molinaro <antho...@alumni.caltech.edu> _______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
