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DataProtector support Multipath Tape?

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In a environment with MSL4048 .... DataProtector support Multipath for tapes?
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When I checked the documentation, HP recommended to keep the second port unconnected -- because you can't do transparent path failovers (I've already explained why it does not work).
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I am afraid, not. Tapes are sequential-access devices where most operations cannot simply be re-tried (like on disks) after a path switch.
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Hi Fernando,

Configuring Multiple Paths to Physical Devices

A device in a SAN environment is usually connected to several clients and can thus be accessed through several paths, that is client names and SCSI addresses (device files on UNIX). Data Protector can use any of
these paths. You can configure all paths to a physical device as a single logical device - multipath device.


For example, a device is connected to client1 and configured as /dev/rs1 and /dev/rs2, on client2 as /dev/r1s1 and on client3 as scsi1:0:1:1. Thus, it can be accessed through four different paths:
client1:/dev/rs1, client1:/dev/rs2, client2:/dev/r1s1 and client3:scsi1:0:1:1. A multipath device therefore contains all four
paths to this tape device.

rgs,
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True, what I meant is that you cannot do a transparent failover, for example if you have dual-port Fibre-Channel attached tape drives in the MSL4048.
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As I take use that feature dual-port of the MSL4048?
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When I checked the documentation, HP recommended to keep the second port unconnected -- because you can't do transparent path failovers (I've already explained why it does not work).
.

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DP does support multiple paths to tape as the one poster reported. When that is configured DP can choose to use a different path to the tape drive in the case that one of them fails so it is a form of fail-over. I don't know if DP handles it transparently but at least the next backup should work.

If you have a backup system administrator who is good with DP and knows how to manage the multi-path features in DP you can use both ports in the tape drives. The comment in the users manual HP recommends just using one port is for most customers who aren't able to manage the complexity of multiple paths.
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Absent Member.
I have a similar question...

Equipment \ Configuration
-HP DP 6.1
-MSL4048 2 LTO-4 Ultrium 1840 Fibre Channel Tape Library
-HP EVA 4400 SAN
-Couple Brocade switches

Various HP servers, some directly attached to the SAN & Tape library and some with local disk and no connection to SAN/Tape Library.

Currently I run two backup jobs, each one utilizes one tape drive in the library and backs up a separate list of servers. I was doing various Multipath settings with a few servers but had a few issues doing it at the same time. Now more servers are connected to the Fibre equipment I'm trying to speed up the backups etc.

Where I would like to get to...

-One backup job
-Destination: Load balanced 2x Ultrium drives in the library
-Servers backing up directly to tape/s at the same time over fibre.

I gather this is possible? To have multiple servers backing up to the same tape library \ drives at the same time over the fibre?

We currently use 4-5 LTO4 tapes nightly.

Thanks
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The last poster may get the best response by posting in the DP forum. What you are asking for is possible but is a fairly advanced configuration and I have not personally configured that with DP. I believe that there is a special license required for a master cell server that controls the library and coordinates with the cells that are writing to tape.

Attempting to have more than one cell writing to the same tape drive and just using scheduling is possible but has to be set up very carefully and is risky as backup window changes or restores can cause conflicts so I wouldn't recommend it.
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