Max_luns in OEL 5.8, uek

Question

Trying to set max_luns parameter on OEL 5.8, uek. Added "options scsi_mod max_luns=4096" into /etc/modprobe.conf, run mkinitrd, reboot. But systool -v -m scsi_mod shows the same numbers.
# systool -v -m scsi_mod
Module = "scsi_mod"
Parameters:
default_dev_flags = "0"
inq_timeout = "20"
max_luns = "512"
max_report_luns = "511"
scan = "async"
scsi_logging_level = "0"
# uname -a
Linux vld-bl15 2.6.32-300.11.1.el5uek. What I'm doing wrong?

Answer 1

http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Cluster_Administration/s1-max-luns-CA.html
It is not necessary to configure max_luns in Red Hat Enterprise Linux 5.
In Red Hat Enterprise Linux releases prior to Red Hat Enterprise Linux 5, if RAID storage in a cluster presents multiple LUNs, it is necessary to enable access to those LUNs by configuring max_luns (or max_scsi_luns for 2.4 kernels) in the /etc/modprobe.conf file of each node. In Red Hat Enterprise Linux 5, cluster nodes detect multiple LUNs without intervention required; it is not necessary to configure max_luns to detect multiple LUNs.
However, the following still works, if you really need to change it:
Edit /etc/grub.conf and add the following to your kernel boot parameter, for instance:
kernel /vmlinuz-2.6.32...... rhgb quiet scsi_mod.max_luns=4096
Edited by: Dude on Mar 29, 2012 7:31 PM