It Depends (tm). > One ZooKeeper is a single point of failure. It goes away and your SolrCloud > cluster is kinda hosed. OTOH, with only 3 servers, the chance that one of > them is going down is low anyway. How lucky do you feel?
> I would be cautious about running your ZK instances embedded, > super-especially if there's only one ZK instance. That couples your ZK > instances with your Solr instances. So if for any reason you want to > stop/start Solr, you will stop/start ZK as well and it's easy to fall below a > quorum. It's perfectly viable to run them embedded, especially on a very > small cluster. You do have to think a bit more about sequencing Solr nodes > going up/down is all. Best, Erick On Sat, Aug 16, 2014 at 7:11 AM, waqas sarwar <waqassarwa...@hotmail.com> wrote: > > >> Date: Thu, 14 Aug 2014 06:51:02 -0600 >> From: s...@elyograg.org >> To: solr-user@lucene.apache.org >> Subject: Re: Replication Issue with Repeater Please help >> >> On 8/14/2014 2:09 AM, waqas sarwar wrote: >> > Thanks Shawn. What i got is Circular replication is totally impossible & >> > Solr fails in distributed environment. Then why solr documentation says >> > that configure "REPEATER" for distributed architecture, because "REPEATER" >> > behave like master-slave at a time. >> > Can i configure SolrCloud on LAN, or i've to configure zookeeper myself. >> > Please provide me any solution for LAN distributed servers. If zookeeper >> > in only solution then provide me any link to configure it that can help me >> > & to avoid wrong direction. >> >> The repeater config is designed to avoid master overload from many >> slaves. So instead of configuring ten slaves to replicate from one >> master, you configure two slaves to replicate directly from your master, >> and then you configure those as repeaters. The other eight slaves are >> configured so that four of them replicate from each of the repeaters >> instead of the true master, reducing the load. >> >> SolrCloud is the easiest way to build a fully distributed and redundant >> solution. It is designed for a LAN. You configure three machines as >> your zookeeper ensemble, using the zookeeper download and instructions >> for a clustered setup: >> >> http://zookeeper.apache.org/doc/r3.4.6/zookeeperAdmin.html#sc_zkMulitServerSetup >> >> The way to start Solr in cloud mode is to give it a zkHost system >> property. That informs Solr about all of your ZK servers. If you have >> another way of setting that property, you can use that instead. I >> strongly recommend using a chroot with the zkHost parameter, but that is >> not required. Search the zookeeper page linked above for "chroot" to >> find a link to additional documentation about chroot. >> >> You can use the same servers for ZK as you do for Solr, but be aware >> that if Solr puts a large I/O load on the disks, you may want the ZK >> database to be on its own disks(s) so that it responds quickly. >> Separate servers is even better, but not strictly required unless the >> servers are under extreme load. >> >> https://cwiki.apache.org/confluence/display/solr/SolrCloud >> >> You will find a "Getting Started" link on the page above. Note that the >> "Getting Started" page talks about a zkRun option, which starts an >> embedded zookeeper as part of Solr. I strongly recommend that you do >> NOT take this route, except for *initial* testing. SolrCloud works much >> better if the Zookeeper ensemble is in its own process, separate from Solr. >> >> Thanks, >> Shawn >> >> Thank you so much. You helped alot. One more question is that can i use only >> one zookeeper server to manage 3 solr servers, or i've to configure 3 >> zookeeper servers for each. >And zookeeper servers should be stand alone or >> better to use same solr server machine ?>>Best Regards,>Waqas
