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Message-ID: <5306708D.6090001@sliderule.demon.co.uk>
Date: Thu, 20 Feb 2014 21:15:57 +0000
From: Steve Burton <steve@sliderule.demon.co.uk>
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To: Dan Nelson <dnelson@allantgroup.com>
Subject: Re: iSCSI Backing store
References: <530661A6.1030606@sliderule.demon.co.uk>
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On 20/02/2014 20:45, Dan Nelson wrote:
> In the last episode (Feb 20), Steve Burton said:
>> I'm trying to familiarize myself with the iSCSI implementation in FreeBSD
>> 10 REL.  I have made a target containing two LUNs which are backed by two
>> files on my test server (redundant PC).  This all worked well though it
>> took ages to make the files using dd.
>>
>> dd if=/dev/zero of=/targets/target0-0 bs=512 count=31250000
>>
>> My first question is, is there a better and quicker way to make the
>> backing store files?
>
> A 512-byte blocksize is suboptimal; you're spending most of your time just
> processing the read/write syscalls at that size.  There isn't much benefit
> to using a blocksize over 64k, but using 1m does make it easy to calculate
> the count for large volumes :)
>
>> My second question relates to making iSCSI LUNs using a disk volume.  I
>> have a second (empty) hard drive.  Is it possible to just use the disk as
>> backing store for iSCSI?
>
> I don't see why not.
>
>
I didn't see why not either but so far I can't see how :)

Steve.