Re: Re : Restoring nodes in a new datacenter, from snapshots in an existing datacenter
thanks Nate. But regarding our situation, of the 3 Datacenters we have DC1 DC2 and DC3, we take backup of snapshots on DC1. If DC3 were to go down, will we not be able to bring up a new DC4 with snapshots and token_ranges from DC1? On Fri, Aug 28, 2015 at 3:19 PM, Nate McCall wrote: > You cannot use the identical token ranges. You have to capture membership > information somewhere for each datacenter, and use that token information > when briging up the replacement DC. > > You can find details on this process here: > > http://docs.datastax.com/en/cassandra/2.0/cassandra/operations/ops_snapshot_restore_new_cluster.html > > That process is straight forward, but it can go south pretty quickly if > you miss a step. It's a really good idea to set asside some time to try > this out in a staging/test system and build a runbook for the process > targeting your specific environment. > > On Fri, Aug 28, 2015 at 1:12 PM, sai krishnam raju potturi < > pskraj...@gmail.com> wrote: > >> >> hi; >> We have cassandra cluster with Vnodes spanning across 3 data >> centers. We take backup of the snapshots from one datacenter. >>In a doomsday scenario, we want to restore a downed datacenter, with >> snapshots from another datacenter. We have same number of nodes in each >> datacenter. >> >> 1 : We know it requires copying the snapshots and their corresponding >> token ranges to the nodes in new datacenter, and running nodetool >> refresh. >> >> 2 : The question is, we will now have 2 datacenters, with the same exact >> token ranges. Will that cause any problem. >> >> DC1 : Node-1 : token1..token10 >> Node-2 : token11 .token20 >> Node-3 : token21 . token30 >> Node-4 : token31 . token40 >> >> DC2 : Node-1 : token1.token10 >>Node-2 : token11token20 >>Node-3 : token21token30 >>Node-4 : token31token40 >> >> >> thanks >> Sai >> >> >> >> > > > -- > - > Nate McCall > Austin, TX > @zznate > > Co-Founder & Sr. Technical Consultant > Apache Cassandra Consulting > http://www.thelastpickle.com >
Re: Re : Restoring nodes in a new datacenter, from snapshots in an existing datacenter
You cannot use the identical token ranges. You have to capture membership information somewhere for each datacenter, and use that token information when briging up the replacement DC. You can find details on this process here: http://docs.datastax.com/en/cassandra/2.0/cassandra/operations/ops_snapshot_restore_new_cluster.html That process is straight forward, but it can go south pretty quickly if you miss a step. It's a really good idea to set asside some time to try this out in a staging/test system and build a runbook for the process targeting your specific environment. On Fri, Aug 28, 2015 at 1:12 PM, sai krishnam raju potturi < pskraj...@gmail.com> wrote: > > hi; > We have cassandra cluster with Vnodes spanning across 3 data centers. > We take backup of the snapshots from one datacenter. >In a doomsday scenario, we want to restore a downed datacenter, with > snapshots from another datacenter. We have same number of nodes in each > datacenter. > > 1 : We know it requires copying the snapshots and their corresponding > token ranges to the nodes in new datacenter, and running nodetool refresh. > > 2 : The question is, we will now have 2 datacenters, with the same exact > token ranges. Will that cause any problem. > > DC1 : Node-1 : token1..token10 > Node-2 : token11 .token20 > Node-3 : token21 . token30 > Node-4 : token31 . token40 > > DC2 : Node-1 : token1.token10 >Node-2 : token11token20 >Node-3 : token21token30 >Node-4 : token31token40 > > > thanks > Sai > > > > -- - Nate McCall Austin, TX @zznate Co-Founder & Sr. Technical Consultant Apache Cassandra Consulting http://www.thelastpickle.com
Fwd: Re : Restoring nodes in a new datacenter, from snapshots in an existing datacenter
hi; We have cassandra cluster with Vnodes spanning across 3 data centers. We take backup of the snapshots from one datacenter. In a doomsday scenario, we want to restore a downed datacenter, with snapshots from another datacenter. We have same number of nodes in each datacenter. 1 : We know it requires copying the snapshots and their corresponding token ranges to the nodes in new datacenter, and running nodetool refresh. 2 : The question is, we will now have 2 datacenters, with the same exact token ranges. Will that cause any problem. DC1 : Node-1 : token1..token10 Node-2 : token11 .token20 Node-3 : token21 . token30 Node-4 : token31 . token40 DC2 : Node-1 : token1.token10 Node-2 : token11token20 Node-3 : token21token30 Node-4 : token31token40 thanks Sai