Linux modprobe.conf file
The /etc/modprobe.conf file must be set to allow the Fibre Channel HBA driver to scan for LUNs greater than 0. Make sure the following line (or something similar) appears in the modprobe.conf file:
options scsi_mod max_luns=255
If the line is not present, add it to the modprobe.conf and enter the following:
#mv /boot/initrd-linux_kernel_version.img
/boot/initrd-linux_kernel_version.img.bak
#mkinitrd -v /boot/initrd-linux_kernel_version.img
linux_kernel_versionwhere the linux_kernel_version is the value that is returned from uname -r (for example, 2.6.9-34.ELsmp).
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