Configuring Multipath Failover

This procedure is optional, but for libraries supporting Multipathing Failover feature, it is important to properly configure the libraries in NODEUM.

Prerequisites

All components in the environment should meet the hardware vendor support standards for this feature. This includes the following:

• Fabric switches

• FC HBAs

• Tape library

OS driver levels and firmware levels of FC HBAs, and library and drives should be of supported revisions.

lin_tape driver

To use the lin_tape device driver software, you need to install the driver. NODEUM has been tested with the latest available lin_tape driver, 3.0.72, which can be downloaded and installed from the IBM fix_central website.

Once you have followed the installation instruction provided by the vendor, you can verify that the driver is well installed:

$ lsmod |grep -i -E 'st|lin_tape'
lin_tape              483328  4
pfo                  1130496  1 lin_tape
st                     65536  0

You can see mediumx and tape drive devices:

$ lsscsi -g | grep -i -E 'medium|tape'
[11:0:0:0]   tape    IBM      ULT3580-HH5      F991  -          /dev/sg3
[11:0:0:1]   mediumx IBM      3573-TL          E.20  -          /dev/sg4
[11:0:1:0]   mediumx ADIC     Scalar i500      100A  -          /dev/sg5
[11:0:2:0]   tape    IBM      ULT3580-HH6      G9P1  -          /dev/sg6

$ cat /proc/scsi/IBMchanger
lin_tape version: 3.0.72
lin_tape major number: 237
Attached Changer Devices:
Number  model       SN                       HBA                       SCSI            FO Path
0       3573-TL     00L2U78AW009_LL0         qla2xxx                   11:0:0:1        NA
1       Scalar i500 VL001AV1506BVV00078      qla2xxx                   11:0:1:0        NA

$ cat /proc/scsi/IBMtape
lin_tape version: 3.0.72
lin_tape major number: 237
Attached Tape Devices:
Number  model       SN                       HBA                       SCSI            FO Path
0       ULT3580-HH5 90WT013124               qla2xxx                   11:0:0:0        NA
1       ULT3580-HH6 90WT054335               qla2xxx                   11:0:2:0        NA

NODEUM Tape Library configuration

In following the standard Tape Library configuration, the tape library has to configured with the lin_tape library and drive emulation.

For doing this, you need to confirm that beside the defined tape library, the Emulation is set with the lin_tape emulation.

This is the same for the Tape Drive(s):