IBM System storage DS6000 Series, Attachment Manual, Page: 142 / 298

SCSI disk considerations for an Intel host running Linux
This section provides information for dynamically adding and removing SCSI disks.
Manually adding and removing SCSI disks
This section provides the steps you must follow to manually add and remove SCSI
disks.
You can unconfigure and remove an unused SCSI disk with the following command:
echo "scsi remove-single-device H B T L" > /proc/scsi/scsi
where
H B T L
are the host, bus, target, and LUN IDs for the device, respectively.
When you add disks to the fabric, you can use either of the following two ways to
force the Linux host to configure them:
v
If the host adapter driver that controls the LUN is not in use, unload it and load
the module again.
v If the driver cannot be unloaded and loaded again, and you know the host, bus,
target and LUN IDs for the new devices, you can add them through the
/proc/scsi/scsi file using the following command:
echo "scsi add-single-device H B T L" > /proc/scsi/scsi
where H B T L are the host, bus, target, and LUN IDs for the device,
respectively.
Note: The Linux kernel does not assign permanent names for the fabric devices in
the /dev directory. For example, a LUN might be /dev/sda. After a driver
reload, the same LUN might become /dev/sdce. A fabric reconfiguration
might also result in a shift in the host, bus, target and LUN IDs, which makes
it unreliable to add specific devices through the /proc/scsi/scsi file.
LUN identification for the Linux host system
This section describes LUN identification for the Linux host system.
[root@yahoo /data]# mkfs -t ext2 /dev/sdb1
mke2fs 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
122112 inodes, 243964 blocks
12198 blocks (5.00%) reserved for the super user
First data block=0
8 block groups
32768 blocks per group, 32768 fragments per group
15264 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
[root@yahoo /data]#
Figure 59. Example of creating a file with the mkfs command
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DS6000 Host Systems Attachment Guide