Linux RHEL Partitioning Limits

harmandeep

harmandeep

VirTuaLiZaTioN Freak
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Was testing partitioning Limits as quoted in our rhel books ...

Both Systems are Virtual Guests under VMware Workstation with a Windows Host.

System1: RHEL 5.2 x86 [ vmware tools installed ] http://pastebin.com/raw.php?i=WZ9XJhYq

System2: RHEL 6.0 x86 [ vmware tools not installed ] RAW OUTPUT L5EwNChq

on Sys1 ... we can see from PASTEBIN that disk was limited to 15 partition no.s whereas as per Linux Partition HOWTO IDE disks have 63 no.s limit.

I had tried to search and i found that the 15 Limit is related to LibATA ...

RHEL5/CentOS5 fdisk refuses to display partitions after 15th ?

As per above post, limit is related to SCSI disks and IDE disks ...

Q1) Why we being limited to 15 no.s partitions on a IDE disk on RHEL ?

Q2) Are we being limited to 15 no.s partitions on a SCSI disk on RHEL due to that LibATA mentioned above?

Q3) Can we override this 15 no.s limitation on RHEL 5.x provided both scsi and ide disks ?

Q4) On Sys2 ... we are being able to create more than 15 no.s of partitions on both IDE and SCSI disk ( although IDE disk are being detected as SCSI on this system ) and yet they aren't having any 15 no.s limit . howcome ?

Regards
 
^^This is slightly off topic--The RHEL 6.0 used by you here is the beta version? If its the final version can you kindly paste the link here to download it.
 
h**p://rhel.ieesee.net/uingei/ ||| or go for torrent ( search for file name/ hash to search )

--- Updated Post - Automerged ---

or sign for rhel evaluation and login to rhn to download 6.x binary isos ... just check'd the same
 
Below Explains the LIMITATION reason :--

This is basically because Linux's SATA support is based on its SCSI

support, which means it inherits the SCSI device numbers. And the SCSI

device numbers were designed for large computers, with lots of

relatively small disks.

As a result, the current device numbering (which goes back to the

beginning of Linux) allows for 128 disks, but only sixteen "minor"

numbers per disk -- one for the whole disk, four for the primary

partitions, and eleven (sdx5 to sdx15) for logical partitions.

Source Info

15 partition limit on SCSI/SATA drives

i.e.

[root@rhel-52-01 ~]# ll /dev/sda*

brw-r----- 1 root disk 8, 0 Jul 28 01:05 /dev/sda

brw-r----- 1 root disk 8, 1 Jul 27 19:36 /dev/sda1

brw-r----- 1 root disk 8, 2 Jul 28 01:05 /dev/sda2

brw-r----- 1 root disk 8, 3 Jul 27 19:36 /dev/sda3

sda Minor Numbers have a limit of 15 (which is currently -> 3) (0 for the Device sda | 1-15 for Partitions )
 
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