On Sun, Dec 18, 2016 at 3:48 PM, GW <thegeofo...@gmail.com> wrote: > Yeah, > > > I'll look at the proxy you suggested shortly. > > I've discovered that the idea of making a zookeeper aware app is pointless > when scripting REST calls right after I installed libzookeeper. > > Zookeeper is there to provide the zookeeping for Solr: End of story. Me > thinks.... > > I believe what really has to happen is: connect to the admin API to get > status > > /solr/admin/collections?action=CLUSTERSTATUS > > I think it is more sensible to make a cluster aware app. > > <lst name="Merchants"><str name="replicationFactor">1</str><lst > name="shards"><lst name="shard1"><str > name="range">80000000-7fffffff</str><str name="state">active</str><lst > name="replicas"><lst name="core_node1"><str > name="core">FrogMerchants_shard1_replica1</str><str name="base_url"> > http://10.128.0.2:8983/solr</str><str > name="node_name">10.128.0.2:8983_solr</str><str > name="state">active</str><str > name="leader">true</str></lst></lst></lst></lst> > > I can get an array of nodes that have a state of active. So if I have 7 > nodes that are state = active, I will have those in an array. Then I can > use rand() funtion with an array count to select a node/url to post a json > string. It would eliminate the need for a load balancer. I think..... > If you send to random(node), there is high chance(increasing with number of nodes/shards) that node won't have the leader, so that node will also redirect it to the leader. What you can do, is compute the hash of the 'id' field locally. with hash-id you will get shard-id (because each shard has the hash-range), and with shard, you will find the leader, and you will find on which node the leader is (cluster-status) and send the request directly to the leader and be certain that it won't be redirected again (less network hops).
> //pseudo code > > $array_count = $count($active_nodes) > > $url_target = rand(0, $array_count); > > // creat a function to pull the url somthing like > > > $url = get_solr_url($url_target); > > I have test sever on my bench. I'll spin up a 5 node cluster today, get my > app cluster aware and then get into some Solr indexes with Vi and totally > screw with some shards. > > If I am correct I will post again. > > Best, > > GW > > On 15 December 2016 at 12:34, Shawn Heisey <apa...@elyograg.org> wrote: > > > On 12/14/2016 7:36 AM, GW wrote: > > > I understand accessing solr directly. I'm doing REST calls to a single > > > machine. > > > > > > If I have a cluster of five servers and say three Apache servers, I can > > > round robin the REST calls to all five in the cluster? > > > > > > I guess I'm going to find out. :-) If so I might be better off just > > > running Apache on all my solr instances. > > > > If you're running SolrCloud (which uses zookeeper) then sending multiple > > query requests to any node will load balance the requests across all > > replicas for the collection. This is an inherent feature of SolrCloud. > > Indexing requests will be forwarded to the correct place. > > > > The node you're sending to is a potential single point of failure, which > > you can eliminate by putting a load balancer in front of Solr that > > connects to at least two of the nodes. As I just mentioned, SolrCloud > > will do further load balancing to all nodes which are capable of serving > > the requests. > > > > I use haproxy for a load balancer in front of Solr. I'm not running in > > Cloud mode, but a load balancer would also work for Cloud, and is > > required for high availability when your client only connects to one > > server and isn't cloud aware. > > > > http://www.haproxy.org/ > > > > Solr includes a cloud-aware Java client that talks to zookeeper and > > always knows the state of the cloud. This eliminates the requirement > > for a load balancer, but using that client would require that you write > > your website in Java. > > > > The PHP clients are third-party software, and as far as I know, are not > > cloud-aware. > > > > https://wiki.apache.org/solr/IntegratingSolr#PHP > > > > Some advantages of using a Solr client over creating HTTP requests > > yourself: The code is easier to write, and to read. You generally do > > not need to worry about making sure that your requests are properly > > escaped for URLs, XML, JSON, etc. The response to the requests is > > usually translated into data structures appropriate to the language -- > > your program probably doesn't need to know how to parse XML or JSON. > > > > Thanks, > > Shawn > > > > >
