[sclug] LVM & 2Tb limit

[Alan Pearson]

This is really confusing.
I've been speaking to Veritas (separate project) who also say they  
suffer from the 2Tb limitation, but it will be addressed in their  
release for RHEL 4.0 but ONLY on 64 bit systems.

So, Q2. Is 2.6 able to address > 2Tb on 32 bit (I.E. Intel Xeon)  
systems ??


Alex, thanks for the info below, but it looks like the limitation is  
still in RHEL 3 ?


On 15 Feb 2005, at 16:42, Alex Butcher wrote:

> On Tue, 15 Feb 2005, Alan Pearson wrote:
>
>> I've read that kernel 2.4 suffers from a 2 TB limitation on Block  
>> devices.
>> I need to create a logical volume of around 12TB on a RHEL 3.0  
>> system, which also runs kernel 2.4 (albeit a RH kernel).
>
> First of all, install the kernel src.rpm and check whether RH have
> integrated the various large fs/block device patches. I'm pretty sure  
> that's
> the sort of thing they've done in the RH_E_L kernel, and I'm pretty  
> sure
> I've seen the patches in the RH7.2 kernel and the like.
>
> <http://www.redhat.com/software/rhel/3features/kernel/> seems to  
> suggest
> that this is the case (see third bullet point from the end of the  
> list), but
> it does seem to be a bit contradictory.
>
> <https://www.redhat.com/archives/nahant-beta-list/2004-October/ 
> msg00004.html>
> also looks like a good place to start reading (found using 'RHEL3 TB  
> "file
> system" site:redhat.com' as the search term).
>
>> Has anyone any ideas if this is possible ? Is this limitation  
>> eliminated
>> in kernel 2.6 / LVM 2?
>
> See above.
>
>> Also is there any disadvantage to having such a large filesystem (I'm  
>> going with reiserfs (I don't want to hear about ext3 !))
>
> Off the top of my head:
>
> - fsck times
> - all your eggs in one basket
>
>> The files that are stored there will be GBs in size so I'm not  
>> imaging hundreds of thousands of files.
>
> Consider tweaking the 'blocks-per-inode' setting when creating the
> filesystem.
>
>> Thanks
>> AlanP
>
> HTH,
> Alex.
> -- 
> Alex Butcher      Brainbench MVP for Internet Security:  
> www.brainbench.com
> Bristol, UK                      Need reliable and secure network  
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