# Few queries on setting up a high performing and scalable ES setup **URL:** \ **Category:** Elasticsearch\ **Created:** [November 17, 2011, 2:49pm UTC](https://discuss.elastic.co/t/few-queries-on-setting-up-a-high-performing-and-scalable-es-setup/5901 "2011-11-17T14:49:46Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Rahul\_Sharma](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@Rahul\_Sharma](https://discuss.elastic.co/u/Rahul_Sharma)\ **Post date:** [November 17, 2011, 2:49pm UTC](https://discuss.elastic.co/t/few-queries-on-setting-up-a-high-performing-and-scalable-es-setup/5901/1 "2011-11-17T14:49:46Z")
Hi, I have been trying out ES for few weeks now and I am pretty convinced that ES is what I would want to use for my project. As I was exploring more, I have few doubts, it would be great if you can help me here: 1. I understand that shards are defined at index creation time and replicas can be added later. So if I have a cluster where I start with 2 nodes with 3 shards and 1 replica and later add more nodes, it would get evenly distributed in 6 nodes (1 shard per node). So basically 7th node is meaningless unless I increase the replica. Am I correct with my understanding? 2. If I get into a situation where I need to increase shards I can do that for the indices that I would create from then by increasing the shard number programatically, Say from now onwards all new indexes will have 5 shards and 1 replica. Is it a fair assumption that, if I add nodes beyond 6th one the shards of new indices will get distributed and the old indices will stay as is with the initial 6 nodes? 3. How a new cluster can help here? When should I use more than one cluster? 4. I read that the distribution happens through primary node and looks like primary node get selected based on startup sequence. If the primary node fails does any of the existing node takes up the responsibilities of a primary node? 5. Is there any benefit of running more than one node in a multi CPU machine? Is is worth running more than one nodes with 5 shards and 1 replica in a EC2 large instance? 6. If I don't use shared File system for permanent storage, rather backup the files under /data folder from local storage, will I be able to recover in case of a node failure just by using the backed up data? 7. I plan to create new indexes after every 1 million docs, is there a limitation on how many indices I can create? Is there any limitation on how many indices I can do a search on without degrading performance in one request (from api its evident that it takes an array of indices)? Once again, hats off to Shay for creating such an awesome product and supporting all alone!! Thanks a lot Rahul ---
**Author:** ![Karussell1](https://avatars.discourse-cdn.com/v4/letter/k/50afbb/32.png) [@Karussell1](https://discuss.elastic.co/u/Karussell1)\ **Post date:** [November 17, 2011, 8:44pm UTC](https://discuss.elastic.co/t/few-queries-on-setting-up-a-high-performing-and-scalable-es-setup/5901/2 "2011-11-17T20:44:19Z")
Hi Rahul, 1+2 -\> have a look into the video on the homepage (below) > 1. How a new cluster can help here? When should I use more than one cluster? e.g. if you have a lot servers in one network and you don't want that they join each other e.g. for different customers or for development/ production separation > does any of the existing node takes up the responsibilities of a primary node? yes > Is there any benefit of running more than one node in a multi CPU machine? yes, you could use e.g. two 32bit instances which reduces every RAM consumption a bit BUT I don't think that it will reduce overall RAM usage. > Is is worth running more than one nodes with 5 shards and 1 replica in a EC2 large instance? I don't think so > just by using the backed up data? have a look, and do not forget to flush > **[Jetslide uses ElasticSearch as Database](https://karussell.wordpress.com/2011/07/13/jetslide-uses-elasticsearch-as-database/)** > > GraphHopper – A Java routing engine karussell ads This post explains how one could use the search server ElasticSearch as a database. I’m using ElasticSearch as my only data storage sys… > Is there any limitation on how many indices I can do a search on without degrading performance in one request Its successfully used from others with thousand of indices/shards but it is not intended for e.g. one index per user ... Regards, Peter. On Nov 17, 3:49 pm, Rahul Sharma [rahul.sharma.co...@gmail.com](mailto:rahul.sharma.co...@gmail.com) wrote: > Hi, > > I have been trying out ES for few weeks now and I am pretty convinced that > ES is what I would want to use for my project. > As I was exploring more, I have few doubts, it would be great if you can > help me here: > > 1. I understand that shards are defined at index creation time and replicas > can be added later. So if I have a cluster where I start with 2 nodes with > 3 shards and 1 replica and later add more nodes, it would get evenly > distributed in 6 nodes (1 shard per node). So basically 7th node is > meaningless unless I increase the replica. Am I correct with my > understanding? > 2. If I get into a situation where I need to increase shards I can do that > for the indices that I would create from then by increasing the shard > number programatically, Say from now onwards all new indexes will have 5 > shards and 1 replica. Is it a fair assumption that, if I add nodes beyond > 6th one the shards of new indices will get distributed and the old indices > will stay as is with the initial 6 nodes? > 3. How a new cluster can help here? When should I use more than one cluster? > 4. I read that the distribution happens through primary node and looks like > primary node get selected based on startup sequence. If the primary node > fails does any of the existing node takes up the responsibilities of a > primary node? > 5. Is there any benefit of running more than one node in a multi CPU > machine? Is is worth running more than one nodes with 5 shards and 1 > replica in a EC2 large instance? > 6. If I don't use shared File system for permanent storage, rather backup > the files under /data folder from local storage, will I be able to recover > in case of a node failure just by using the backed up data? > 7. I plan to create new indexes after every 1 million docs, is there a > limitation on how many indices I can create? Is there any limitation on how > many indices I can do a search on without degrading performance in one > request (from api its evident that it takes an array of indices)? > > Once again, hats off to Shay for creating such an awesome product and > supporting all alone!! > > Thanks a lot > Rahul ---
**Author:** ![Rahul\_Sharma](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@Rahul\_Sharma](https://discuss.elastic.co/u/Rahul_Sharma)\ **Post date:** [November 21, 2011, 9:42pm UTC](https://discuss.elastic.co/t/few-queries-on-setting-up-a-high-performing-and-scalable-es-setup/5901/3 "2011-11-21T21:42:57Z")
Thanks Peter for the answers!! On Fri, Nov 18, 2011 at 2:14 AM, Karussell [tableyourtime@googlemail.com](mailto:tableyourtime@googlemail.com)wrote: > Hi Rahul, > > 1+2 -\> have a look into the video on the homepage (below) > > > 1. How a new cluster can help here? When should I use more than one > > cluster? > > e.g. if you have a lot servers in one network and you don't want that > they join each other e.g. for different customers or for development/ > production separation > > > does any of the existing node takes up the responsibilities of a primary > > node? > > yes > > > Is there any benefit of running more than one node in a multi CPU > > machine? > > yes, you could use e.g. two 32bit instances which reduces every RAM > consumption a bit BUT I don't think that it will reduce overall RAM > usage. > > > Is is worth running more than one nodes with 5 shards and 1 replica in a > > EC2 large instance? > > I don't think so > > > just by using the backed up data? > > have a look, and do not forget to flush > > [Jetslide uses ElasticSearch as Database | Karussell](http://karussell.wordpress.com/2011/07/13/jetslide-uses-elasticsearch-as-database/) > > > Is there any limitation on how many indices I can do a search on without > > degrading performance in one request > > Its successfully used from others with thousand of indices/shards but > it is not intended for e.g. one index per user ... > > Regards, > Peter. > > On Nov 17, 3:49 pm, Rahul Sharma [rahul.sharma.co...@gmail.com](mailto:rahul.sharma.co...@gmail.com) wrote: > > > Hi, > > > > I have been trying out ES for few weeks now and I am pretty convinced > > that > > ES is what I would want to use for my project. > > As I was exploring more, I have few doubts, it would be great if you can > > help me here: > > > > 1. I understand that shards are defined at index creation time and > > replicas > > can be added later. So if I have a cluster where I start with 2 nodes > > with > > 3 shards and 1 replica and later add more nodes, it would get evenly > > distributed in 6 nodes (1 shard per node). So basically 7th node is > > meaningless unless I increase the replica. Am I correct with my > > understanding? > > 2. If I get into a situation where I need to increase shards I can do > > that > > for the indices that I would create from then by increasing the shard > > number programatically, Say from now onwards all new indexes will have 5 > > shards and 1 replica. Is it a fair assumption that, if I add nodes beyond > > 6th one the shards of new indices will get distributed and the old > > indices > > will stay as is with the initial 6 nodes? > > 3. How a new cluster can help here? When should I use more than one > > cluster? > > 4. I read that the distribution happens through primary node and looks > > like > > primary node get selected based on startup sequence. If the primary node > > fails does any of the existing node takes up the responsibilities of a > > primary node? > > 5. Is there any benefit of running more than one node in a multi CPU > > machine? Is is worth running more than one nodes with 5 shards and 1 > > replica in a EC2 large instance? > > 6. If I don't use shared File system for permanent storage, rather backup > > the files under /data folder from local storage, will I be able to > > recover > > in case of a node failure just by using the backed up data? > > 7. I plan to create new indexes after every 1 million docs, is there a > > limitation on how many indices I can create? Is there any limitation on > > how > > many indices I can do a search on without degrading performance in one > > request (from api its evident that it takes an array of indices)? > > > > Once again, hats off to Shay for creating such an awesome product and > > supporting all alone!! > > > > Thanks a lot > > Rahul ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 3:48am UTC](https://discuss.elastic.co/t/few-queries-on-setting-up-a-high-performing-and-scalable-es-setup/5901/4 "2017-07-06T03:48:00Z")