Scan And Verify The Storage Logical Drive - IBM System Storage DS3500 Introduction And Implementation Manual

Linux Config.fm
available types, because this is the part of the configuration dealing with heterogeneous host
support. Each operating system expects slight variations in settings and can handle SCSI
commands separately. Incorrect selections can result in failure to boot, or loss of path failover
function when attached to the storage server.
For RDAC and DMM always use the Linux host type. When you are using clustering services
the correct host type would be LNXCluster.
LNXAVT option is used when third-party multipath drivers are installed. For example to use
Dynamic Multi-pathing (DMP) as the default multipath driver. DMP is part of VERITAS
Volumen Manager.

20.1.4 Scan and verify the storage logical drive

During the server restart, you will see a list of devices listed below the corresponding LSI SAS
adapter, and the list should be similar to Figure 20-13. This shows that the SAS adapter
installed in slot 1 is accessing the same logical drive (LUN 0) from the IBM System Storage
DS3500 by four different paths. One path for each SAS port connected to the Storage as
shown in Figure 20-1 on page 604.
Figure 20-13 SAS adapters device list
At this point, we already should have the necessary modules in the Linux OS to scan the
logical drives. The lsmod command can be used to verify that the RDAC (MPP) modules are
running. The output of the command will list the following modules:
mppUpper
mppVhba
sg
sd_mod
scsi_mod
If all of these modules are running, the RDAC should be able to manage access to the
DS3500 logical drive. It is possible to verify this using the following procedure:
A similar directory structure as shown in Example 20-3 on page 613 is created by the RDAC
multipath driver. We will have a directory for each Storage Controller (A and B), one directory
for each controller port and one file for each LUN showing its status very similar to
Example 20-4 on page 613.
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IBM System Storage DS3500: Introduction and Implementation Guide
Draft Document for Review March 28, 2011 12:24 pm