topic Re: Redhat Max luns in Operating System - Linux

Redhat Max luns

Francesca Watts — Tue, 30 Mar 2010 09:07:59 GMT

I am reading 255 SCSI luns are the limit of RHEL 4 OS ? But also see conflicting reports this limit could be per HBA. Can anyone confirm either or?

Many thanks

Re: Redhat Max luns

skt_skt — Tue, 30 Mar 2010 13:19:08 GMT

They are tunable from HBA too.But practically i dont have a linux system which need more than 100 LUN.

#cat /etc/modprobe.conf
##options scsi_mod max_luns=16384 max_report_luns=16384

Re: Redhat Max luns

Vipulinux — Tue, 30 Mar 2010 13:31:07 GMT

Hi

255 is correct.

Have a look at this:
"http://www.redhat.com/docs/manuals/csgfs/browse/4.6/Cluster_Administration/s1-max-luns-CA.html"

Cheers
Vipul

Re: Redhat Max luns

Steven E. Protter — Tue, 30 Mar 2010 18:15:37 GMT

Shalom,

255 is a pretty large number of LUNS.

You may using HP servers and storage be able to exceed that limit with an PSP customized kernel.

However you might want to assess your plans to see if you can go with larger luns.

SEP