High Availability Solutions

Question

I'm searching around a solution for our enterprise application that is responsible to save(and manipulate) historical data of industrial devices. Now, we have two stations that works like hot redundant of each other. Our challenge is in case of failure. For now, our application is responsible to handling fault by synchronizing the files that changed during the fault, by itself. Our application is running on two totally independent machines (one as redundant) and so each one has its own disk. We are searching around a solution like a "high available transparent file system" that makes the fault transparent to the application, so in case of fault, redundant machine still can access the files even the master machine is down (replica issue or such a thing). there is solutions like distributed fault tolerant file systems, distributed-disk software-RAID like FlexRAID and some more solutions, but they all have some challenges and issues. Also it's notable that our application is a .net application and the hardware of machines are not so powerful and are commodity. If you have any solution, I will appreciate to tell me.

Regards

Answer 1

You've not mentioned anything about budget, so I'll spend what I want ;)

In an ideal world you would want a pair of SANs running in a mirrored configuration with a clustered pair of CIFS head units using a failover IP in active/standby mode. Your workstations will then communicate with the active CIFS head unit which gets its data from the SANs.

• If a disk fails in a SAN it should carry on until the disk is replaced (RAID).
• If a SAN fails the other SAN is still available.
• If a CIFS head unit fails the other head unit takes over.

Pros

• SANs can be remotely located to prevent data loss in the case of eg fire or eathquake.
• Multiple workstations can simultaneously access the same files through the CIFS head unit.

Cons

• This is an enterprise grade storage solution and not to be undertaken lightly
• It's not going to be cheap.