topic Re: How many disks does RedHatLinuxsupport? in Operating System - Linux

How many disks does RedHatLinuxsupport?

Natalia Watanabe — Tue, 11 Oct 2005 00:31:17 GMT

I have an Integrity rx4640 server connected to an EVA4000 and every time that I add a disk in the EVA and I present it to the server it appears as /dev/sdX, where X is a letter. My question is: How many disks I can add in the RedHat Enterprise Linux AS? Does some operating system limit that prevents me to add more disks exist?

Re: How many disks does RedHatLinuxsupport?

GGA — Tue, 11 Oct 2005 01:53:43 GMT

hello

Maximum filesystem size (Ext3)
ver. 2.1 ver.3 ver. 4
1TB 1TB 8TB

on hardisk there is no limit
regards
gga

Re: How many disks does RedHatLinuxsupport?

Natalia Watanabe — Tue, 11 Oct 2005 02:13:11 GMT

Thank you for the answer. I would like to know how many disks can I add. For example if I have disks from "/dev/sda" to "/dev/sdz", in that case, Can I add more disks? How many disks can I add, instead of the filesystems size?
Is there some operating system parameter that limits the number of disks that can be mounted?

Re: How many disks does RedHatLinuxsupport?

Gopi Sekar — Tue, 11 Oct 2005 02:21:44 GMT

I don't see any limit other than the device major and minor number limitation.

if you check the /dev/sdX file, it has major and minor numbers associated with it. You can have at 255 minor numbered devices (like sda1, sda2, to sda255).

Also the file system has limitation which, I believe, is defined in the kernel

Hope this helps,
Gopi

Re: How many disks does RedHatLinuxsupport?

Ivan Ferreira — Tue, 11 Oct 2005 08:22:27 GMT

Once you reach /dev/sdz, you will get /dev/sdaa, /dev/sdab, etc. Then /dev/sdba /dev/sdbb, and so.

Re: How many disks does RedHatLinuxsupport?

Rick Garland — Tue, 11 Oct 2005 09:07:43 GMT

As many disks as the EVA has.

Re: How many disks does RedHatLinuxsupport?

Steven E. Protter — Tue, 11 Oct 2005 11:41:55 GMT

There are limits based on performance that will get you long before any theoretical limits will stop you. Too many disks on the daisy chain will flood your i/o channels.

Its true that the real limitation is the EVA, not the OS. The EVA presents LUN's logical disks to the OS. The number of disks in the LUN effects performance but does not count toward any limits.

SEP