Open Stack

>> I have issue with creating shared storage for Openstack. Main idea is to 
>> create 100% redundant shared storage from two servers (kind of network 
>> RAID from two servers).
>> I have two identical servers with many disks inside. What solution can 
>> any one provide for such schema? I need shared storage for running VMs 
>> (so live migration can work) and also for cinder-volumes.

>> One solution is to install Linux on both servers and use DRBD + OCFS2, 
>> any comments on this?
>> Also I heard about Quadstor software and it can create network RAID and 
>> present it via iSCSI.

My two cents worth from a generic concept point view of a network mirror

Key factors to evaluate
1. Write latency
2. Active-active or use active-passive with automatic ip address failover (using CARP etc)
3. Split brain handling
4. How soon after a node failure are the two node brought in sync.

quadstor shines in many aspects and  DRBD + SCST is a good alternative. You should evaluate both in my opinion.

-Tia