Hi,
I am doing a PoC of a RAC architecture built with two node servers with local NVME disks, which I want to use as main disks for the database db group.
I was searching for a solution that can provide high io for an db consolidation project.
I don’t have requirements about space. What I found was very expensive storage SAN solutions using all flash storage systems from different vendors EMC, Hitschi, IBM.
After some investigations I found some solutions like flashgrid.io. These solutions use the Oracle RAC stretched cluster concept . The nodes are equipped with local NVME disks and use high speed interconnect ( 40, 100Gbps ethernet or Infiniband) . Then these disks are shared between nodes using iscsi.
According to some spec the average io for one nvme disk is about 500k IOPS read and 350k write which is a really big numbers. With a 10 Gbps ethernet you can achieve around 80 K iops on an iscsi shared disk using the latest RDMA technologies.
I am trying to explore this concept and I made a lab in vbox with two nodes.
each node has one defined nvme disk . I am using a third node for providing shared storage for voting disk, cr and quorum disks.
I shared the local nvme disks using iscsi , then i use udev rules to make the name of local and shared disks consistent.
I managed to install grid infrastructure and I managed to create a disk group using the shared local disks. I am continuing testing.
I am posting this because I found almost zero information about this concept.
The next step is to install a DB using the new db group and to test redundancy and availability.
Still I don‘t know can i use such disk sharing a local disk is shared using iscsi target. The first node uses local block device the second node accesses the same disk through iscsi.
regards
Cvetan