Yes they do have same group id. On Wed, Aug 3, 2022, 4:35 PM Tsz Wo Sze <[email protected]> wrote:
> Hi Swapnil, > > We should use the same group configuration (i.e. the same set of servers) > to start up the servers. Otherwise, there is no way to compute "majority" > correctly. > > BTW, they should also have the same group id. Are they? > > Tsz-Wo > > > On Wed, Aug 3, 2022 at 1:54 PM Swapnil Tailor <[email protected]> > wrote: > >> Yes all the servers are having the same RaftGroup but the peer list could >> be different (i.e. Serve A could have peer list: [A, B], and Server B could >> have peer list: [B, C]). >> Reason they won't see all the servers up at the same time. And that's why >> we want to know if we can add the other peers in the raft group later after >> the server start up. And what is the right way of doing that. >> >> On Wed, Aug 3, 2022 at 1:44 PM Tsz Wo Sze <[email protected]> wrote: >> >>> Hi Swapnil, >>> >>> Thanks for trying Ratis! >>> >>> Are they starting with the same RaftGroup? All servers A, B and C >>> should have the same RaftGroup(A, B, C) when they start up. >>> >>> Tsz-Wo >>> >>> On Wed, Aug 3, 2022 at 1:32 PM Swapnil Tailor <[email protected]> >>> wrote: >>> >>>> Hello, >>>> >>>> We are trying to use ratis library to our existing Presto Distributed >>>> query engine. We are facing one issue while working on updating the peers >>>> in the cluster: >>>> >>>> Ratis Server runs on multiple resource managers, and it takes time for >>>> them to get up and join the cluster. So we require the Ratis server to have >>>> atleast 2 server before it starts the server. This works well. But the >>>> issue happens in the leader selection as mentioned below: >>>> 1. There are 3 ratis servers in the cluster, A, B, C >>>> 2. With server A seeing serve B, the minimum server count matches and >>>> it starts the server with peers list as A, B >>>> 3. Now when server C starts, we try to update the peer list using >>>> client api: >>>> RaftClient.admin().setContfiguration(updated peer list), but for >>>> some reason this is not working correctly and there are multiple leaders >>>> getting elected in the cluster. >>>> >>>> Can someone help understand how should we fix that? And also if the >>>> peer updation logic is correct by each server running RaftClient and update >>>> the configuration as and when it sees the peer list has changes (i.e. a new >>>> server joins the cluster/existing one dies/replaced). >>>> >>>> Also side question: Can someone invite me to the slack channel to be >>>> part of the community? >>>> >>>> Thanks in advance, >>>> Swapnil >>>> >>>
