RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?

[Russell Lewis <russelll@us.ibm.com>]

Actually, Julian is very close to what I envision.  I have 3 old computers
currently, and plan to have more soon.  It's frustrating to have my disk
space spread across multiple devices.  My long-range target is to have a
single iSCSI Target computer, with multiple other computers (both legacy
computers and new) booting off of iSCSI disks.  All computers will be
diskless except for the iSCSI target.  The iSCSI Target will pool all of my
available storage, as well as do RAID protection.

Of course, this works best when the iSCSI target machine implements storage
overallocation, point-in-time flash copy, and other advanced features.

I know that I could, for some purposes, just boot off of NFS, but I would
prefer a solution that allows me to install legacy OSes on legacy computers
- and to install modern OSes without software changes.

For example, I have one computer that I use just to keep an eye on RedHat's
latest version.  Every few months, I do a complete reinstall with RedHat's
net-install process.  If that has the capability to install on a remote NFS
share, I don't know how...





|---------+---------------------------->
|         |           Robert Snively   |
|         |           <rsnively@Brocade|
|         |           .COM>            |
|         |                            |
|         |           04/15/2003 08:34 |
|         |           AM               |
|         |                            |
|---------+---------------------------->
  >------------------------------------------------------------------------------------------------------------------------------|
  |                                                                                                                              |
  |       To:       "'Julian Satran'" <Julian_Satran@il.ibm.com>, Sukanta ganguly <sganguly@yahoo.com>                           |
  |       cc:       ips@ece.cmu.edu, owner-ips@ece.cmu.edu, Robert Snively <rsnively@Brocade.COM>, Russell Lewis/Tucson/IBM@IBMUS|
  |       Subject:  RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?                                              |
  |                                                                                                                              |
  >------------------------------------------------------------------------------------------------------------------------------|




What you have described is not a diskless environment.  It is a disk-full
environment
with local disks, a well supported and very cheap environment that receives
no benefit from iSCSI and is frequently implemented with traditional SCSI
or
ATA and will soon be implemented with SATA.

If you create the local iSCSI home target, you still have not provided the
diskless
environment to the legacy hosts you intend to attach to that target.  If
you have more
than one such host, you must introduce non-legacy software and management
tools.
In most cases, you could have just attached your $500 brick directly and
saved
yourself the cost (and hassle of managing) the extra Linux PC target.

It looks to me like we still have some confusion interpreting Russell's
original intent.

Bob
 -----Original Message-----
 From: Julian Satran [mailto:Julian_Satran@il.ibm.com]
 Sent: Monday, April 14, 2003 10:50 PM
 To: Sukanta ganguly
 Cc: ips@ece.cmu.edu; owner-ips@ece.cmu.edu; Robert Snively; 'Russell
 Lewis'
 Subject: RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?


 We did run "informal" tests using Windows/Office+Personal-Web-server (a
 usual home/SOHO setup) on switched 100Mb/s (also common at home).
 The disks we attached to where better than the ordinary desktop IDE drives
 (we where using the now defunct 200i - but I have seen an inexpensive
 small array (looks like a larger brick two weeks ago at Fry's for $500 -
 if you put those behind a (not very old) PC running Linux you can have a
 decent and inexpensive home target). Webserver  and Office where showing
 better numbers - and the perceived response time on clients was better.

 Julo

                                                                           
 Sukanta ganguly                                                           
 <sganguly@yahoo.com>                                                      
                                                                           
                                                                        To 
 15/04/03 05:23                     Julian Satran/Haifa/IBM@IBMIL, Robert  
                                    Snively <rsnively@Brocade.COM>         
                                                                        cc 
                                    ips@ece.cmu.edu,                       
                                    owner-ips@ece.cmu.edu, Russell         
                                    Lewis/Tucson/IBM@IBMUS                 
                                                                   Subject 
                                    RE: Are there any coming iSCSI HBAs?   
                                    Preferably at 100Mb speed?             
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           





 Hi,

    For a diskless environment multiple other issues
 have to come into play, i.e Network based remote boot
 logic, proper downlod of enough Operating System code
 onto the diskless box etc.

    Julo, what kinds of numbers did you folks see ?
 What is your environment like ? I am a little
 perplexed with the high speed connection to the remote
 disks via iSCSI.

 Thanks
 SG


 --- Julian Satran <Julian_Satran@il.ibm.com> wrote:
 > Bob,
 >
 > I wonder if your opinion is based on real experience
 > or prejudice.
 > Our measurements indicate that an inexpensive box
 > with SCSI disks performs
 > BETTER than an IDE (typical) desktop drive
 > using iSCSI over a 100MB/s connection (widely
 > available for home use) -
 > and that includes paging (usually marginal) and all
 > the rest.
 >
 >         Julo
 >
 >
 >
 > Robert Snively <rsnively@Brocade.COM>
 > Sent by: owner-ips@ece.cmu.edu
 > 14/04/03 18:06
 >
 > To
 > Russell Lewis/Tucson/IBM@IBMUS, ips@ece.cmu.edu
 > cc
 >
 > Subject
 > RE: Are there any coming iSCSI HBAs?  Preferably at
 > 100Mb speed?
 >
 >
 >
 >
 >
 >
 > My experience with diskless workstations is that
 > they are limited by paging activity and background
 > updating to really unacceptable performance, even in
 >
 > simple word-processing programs like frame maker
 > doing medium sized books, and even on a local 10
 > Mb/s
 > network.
 > You are far better off running a workstation with
 > a local disk for system and swap, but running
 > dataless.  NFS or comparable networking programs
 > run fine for that.  The local caching of the files
 > on disk and in memory assure adequate performance,
 > while
 > the maintenance of your data remotely assures
 > appropriate centralized data management and backup.
 > Remember too, that it is a rare broadband connection
 >
 > that gives you anything approaching 100 Mb/s.  A T1
 > DSL link
 > is specified at 1.54 Mb/s, and it is the fastest of
 > the
 > common broadband links.
 > In addition, there is nothing more frustrating than
 > being
 > unable to operate because your link is down or
 > severely
 > congested, something that happens far more often
 > than the
 > unavailability of a local disk.
 > My view?  iSCSI is not an appropriate protocol for
 > home
 > networking data access.  Use your IDE or SATA drive
 > locally
 > for boot, swap, system, and any hot programs and use
 >
 > NFS or other remote file access program against a
 > remote
 > server for data and other programs.
 > Bob Snively
 > 408-333-8135
 > rsnively@brocade.com
 > > -----Original Message-----
 > > From: Russell Lewis [mailto:russelll@us.ibm.com]
 > > Sent: Friday, April 11, 2003 9:25 AM
 > > To: ips@ece.cmu.edu
 > > Subject: Are there any coming iSCSI HBAs?
 > Preferably at 100Mb speed?
 > >
 > >
 > >
 > >
 > >
 > >
 > > Does anybody know of any current or coming iSCSI
 > HBAs which
 > > show up (to the
 > > BIOS) as ordinary SCSI adapters?  I'd like to drop
 > such an HBA into a
 > > legacy computer and run a totally diskless
 > workstation at home.
 > >
 > > However, since it will be a home computer, I'm
 > willing to
 > > operate at 100Mb
 > > speed - I'm willing to eat the performance hit.
 > It seems to me that
 > > somebody could make an iSCSI HBA with a 100Mb
 > interface and make it
 > > affordable for the home user (say, $50-$100).
 > Anybody know
 > > of such plans?
 > >
 > >
 >


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