hp-ux data protector

[tanislavm]

hi,

I am new in data protector and i like to check if using hp-ux data protector between 2 SAN far apart how are the things:

- every I/O from a box within one site will goes first to the SAN in that site and then this SAN will send over the wan to the far apart SAN.

- from a box within one site how the disks are seen?As disks who pertain the each SAN or as disks to pertain only to the SAN from the site with the box?

- if there is some equipment between the 2 SANs acting like scsi initiator?

- the traffic between SANs is over special link and not involve any server?

tnx

marius

P.S.This thread has been moved from Storage>General  to Storage Area Networks (SAN) (Enterprise)- HP Forums Moderator

[Matti_Kurkela]

Data Protector is a backup software.

Your questions seem to be more related to HP Continuous Access, the storage replication solution for HP EVA and XP storage arrays.

[tanislavm]

Hi MK or everyone,

I apologize to my mistake.I wish anyway the answer to my questions which are related to Data replication into an geografic or campus framework.

tnx.

marius

[Matti_Kurkela]

I'm not a storage admin, and not really familiar with HP enterprise storage products (I've worked more with EMC storage). But I'll tell you what I know...

> - from a box within one site how the disks are seen?As disks who pertain the each SAN or as disks to pertain only to the SAN from the site with the box?

Usually the server will see just the LUNs from the local storage. But a manufacturer-specific information tool (like evainfo/xpinfo for HP storage) may be able to tell you that the LUNs are replicated to a remote storage system, the same way it might tell you the RAID level used for the LUNs.

The behavior of the LUNs may be a bit different from the regular non-replicated LUNs, though: if the strictest possible replication policy is chosen, the local storage system will not report to the server that the write operation is complete until the data is successfully passed to the remote storage and written to the disks there. Obviously, this can make replicated storage work much slower than non-replicated one, but this is the safest way to run the replication. If you can accept some amount of risk, there may be other options: for example, the operation might be considered "completed" when the data has successfully been copied to the battery-backed cache in the remote storage system, and the remote storage can do the actual writing to the disks asynchronously.

> - the traffic between SANs is over special link and not involve any server?

Yes, I understand this is the way it usually works.