Instaclustr's done some analysis around "optimal" number of vnodes to use - https://www.instaclustr.com/cassandra-vnodes-how-many-should-i-use/ I might be able to provide more details if you're interested.
As, Sean said, you can create the new DC with different number of vnodes. Kind Regards, *Gregory Raevski* On Thu, 14 Mar 2019 at 05:11, Durity, Sean R <sean_r_dur...@homedepot.com> wrote: > Rebuild the DCs with a new number of vnodes… I have done it. > > > > Sean > > > > *From:* Ahmed Eljami <ahmed.elj...@gmail.com> > *Sent:* Wednesday, March 13, 2019 2:09 PM > *To:* user@cassandra.apache.org > *Subject:* Re: [EXTERNAL] Re: Cluster size "limit" > > > > Is not possible with an existing cluster! > > Le mer. 13 mars 2019 à 18:39, Durity, Sean R <sean_r_dur...@homedepot.com> > a écrit : > > If you can change to 8 vnodes, it will be much better for repairs and > other kinds of streaming operations. The old advice of 256 per node is now > not very helpful. > > > > Sean > > > > *From:* Ahmed Eljami <ahmed.elj...@gmail.com> > *Sent:* Wednesday, March 13, 2019 1:27 PM > *To:* user@cassandra.apache.org > *Subject:* [EXTERNAL] Re: Cluster size "limit" > > > > Yes, 256 vnodes > > > > Le mer. 13 mars 2019 à 17:31, Jeff Jirsa <jji...@gmail.com> a écrit : > > Do you use vnodes? How many vnodes per machine? > > -- > > Jeff Jirsa > > > > > On Mar 13, 2019, at 3:58 PM, Ahmed Eljami <ahmed.elj...@gmail.com> wrote: > > Hi, > > > > We are planning to add a third datacenter to our cluster (already has 2 > datacenter, every datcenter has 50 nodes, so 100 nodes in total). > > > > My fear is that an important number of nodes per cluster (> 100) could > cause a lot of problems like gossip duration, maintenance (repair...)... > > > > I know that it depends on use cases, volume of data and many other thing, > but I would like that you share your experiences with that. > > > > Thx > > > > > > > > > ------------------------------ > > > The information in this Internet Email is confidential and may be legally > privileged. It is intended solely for the addressee. Access to this Email > by anyone else is unauthorized. If you are not the intended recipient, any > disclosure, copying, distribution or any action taken or omitted to be > taken in reliance on it, is prohibited and may be unlawful. When addressed > to our clients any opinions or advice contained in this Email are subject > to the terms and conditions expressed in any applicable governing The Home > Depot terms of business or client engagement letter. The Home Depot > disclaims all responsibility and liability for the accuracy and content of > this attachment and for any damages or losses arising from any > inaccuracies, errors, viruses, e.g., worms, trojan horses, etc., or other > items of a destructive nature, which may be contained in this attachment > and shall not be liable for direct, indirect, consequential or special > damages in connection with this e-mail message or its attachment. > > > ------------------------------ > > The information in this Internet Email is confidential and may be legally > privileged. It is intended solely for the addressee. Access to this Email > by anyone else is unauthorized. If you are not the intended recipient, any > disclosure, copying, distribution or any action taken or omitted to be > taken in reliance on it, is prohibited and may be unlawful. When addressed > to our clients any opinions or advice contained in this Email are subject > to the terms and conditions expressed in any applicable governing The Home > Depot terms of business or client engagement letter. The Home Depot > disclaims all responsibility and liability for the accuracy and content of > this attachment and for any damages or losses arising from any > inaccuracies, errors, viruses, e.g., worms, trojan horses, etc., or other > items of a destructive nature, which may be contained in this attachment > and shall not be liable for direct, indirect, consequential or special > damages in connection with this e-mail message or its attachment. >
