# Understanding Curator's --master-only flag **URL:** \ **Category:** Elasticsearch\ **Created:** [September 22, 2014, 7:43pm UTC](https://discuss.elastic.co/t/understanding-curators-master-only-flag/19922 "2014-09-22T19:43:10Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![mhughes](https://avatars.discourse-cdn.com/v4/letter/m/85e7bf/32.png) [@mhughes](https://discuss.elastic.co/u/mhughes)\ **Post date:** [September 22, 2014, 7:43pm UTC](https://discuss.elastic.co/t/understanding-curators-master-only-flag/19922/1 "2014-09-22T19:43:10Z")
I'm running curator in every node in an N-node ELK cluster. Is there any reason I _wouldn't_ want to have the --master-only flag turned on? If you delete an index from the master, it's still going to get deleted from the other nodes right? I'm trying to understand why you would ever not want to set this. > **[elastic/curator](https://github.com/elastic/curator/wiki)** > > curator - Curator: Tending your Elasticsearch indices -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/0e4c4006-609b-41cf-b3b5-499d5b7a497e%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/0e4c4006-609b-41cf-b3b5-499d5b7a497e%40googlegroups.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**Author:** ![theuntergeek](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/theuntergeek/32/44961_2.png) [@theuntergeek](https://discuss.elastic.co/u/theuntergeek)\ **Post date:** [September 22, 2014, 9:00pm UTC](https://discuss.elastic.co/t/understanding-curators-master-only-flag/19922/2 "2014-09-22T21:00:40Z")
You are correct in understanding that indices are deleted completely, regardless of where its shards may reside. This flag exists so that curator + the cron jobs can be installed—usually for configuration management reasons—on ALL nodes in the cluster, but only actually execute when run on the _elected_ master node (as opposed to merely an _eligible_ master node). If you try to run curator with this flag and the IP & port it is pointed at is _not_ the elected master, it will not complete the operations you specify, but will exit with a message indicating it was not run on the elected master. --Aaron On Monday, September 22, 2014 2:43:10 PM UTC-5, Matt Hughes wrote: > I'm running curator in every node in an N-node ELK cluster. Is there any > reason I _wouldn't_ want to have the --master-only flag turned on? > > If you delete an index from the master, it's still going to get deleted > from the other nodes right? I'm trying to understand why you would ever > not want to set this. > > [Create new page · elastic/curator Wiki · GitHub](https://github.com/elasticsearch/curator/wiki/Master-Only) -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/20c2b134-be67-41b9-aca3-70cbe295defd%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/20c2b134-be67-41b9-aca3-70cbe295defd%40googlegroups.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**Author:** ![theuntergeek](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/theuntergeek/32/44961_2.png) [@theuntergeek](https://discuss.elastic.co/u/theuntergeek)\ **Post date:** [September 22, 2014, 9:03pm UTC](https://discuss.elastic.co/t/understanding-curators-master-only-flag/19922/3 "2014-09-22T21:03:55Z")
In short, you are correct. You want that flag set on every node since you've pushed curator to every node. --Aaron On Monday, September 22, 2014 4:00:41 PM UTC-5, Aaron Mildenstein wrote: > You are correct in understanding that indices are deleted completely, > regardless of where its shards may reside. > > This flag exists so that curator + the cron jobs can be installed—usually > for configuration management reasons—on ALL nodes in the cluster, but only > actually execute when run on the _elected_ master node (as opposed to > merely an _eligible_ master node). > > If you try to run curator with this flag and the IP & port it is pointed > at is _not_ the elected master, it will not complete the operations you > specify, but will exit with a message indicating it was not run on the > elected master. > > --Aaron > > On Monday, September 22, 2014 2:43:10 PM UTC-5, Matt Hughes wrote: > > > I'm running curator in every node in an N-node ELK cluster. Is there any > > reason I _wouldn't_ want to have the --master-only flag turned on? > > > > If you delete an index from the master, it's still going to get deleted > > from the other nodes right? I'm trying to understand why you would ever > > not want to set this. > > > > [Create new page · elastic/curator Wiki · GitHub](https://github.com/elasticsearch/curator/wiki/Master-Only) -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/2bc11fc3-35be-4912-a43e-f1627b983f15%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/2bc11fc3-35be-4912-a43e-f1627b983f15%40googlegroups.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**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, 1:00am UTC](https://discuss.elastic.co/t/understanding-curators-master-only-flag/19922/4 "2017-07-06T01:00:33Z")