On Sat, 3 Jul 2004 22:17:24 -0400, Rahul Parasnis <rahulparasnis AT MSN DOT COM>
wrote:
>Hello Gurus,
>
>We are in a process of building a new environment for networker in new
>premises .
>
>Data backup size is estimated to grow to 2 Tera bytes( Currently around
800
>GB/day ) per day in 3 years considering the backup window 8 hours from 10
>:30 PM . Please consider we need faster recovery as well.
>I know I have to tell you lot of other things ( Assume 5 Windows Cluster
(
>together 600 GB in size ) on HP UX Cluster with 175 GB ) and there are 40
>other Unix clients ( 1.3 GB Each )small Ultra 5/ V120 Machines .
>( Server configuration for all above clients I am going for is V240 2CPU
>with 2 GB Memory )
So a total of 5275 GB at full blast a 1GB/s network will give you 3500 GB
transfer in your 10 hour window, so careful scheduling of your backups
should allow a weekly full rest incremental cycle (if everything else can
keep up with it!).
>
>I have few questions and need your advise in selecting Tape library /
>networker configuration
>I have tried to give as mush as information as possible .
>1.
>we are assuming to have GB backup network for big clients . We have Notes
>server having 200 GB finishes in 6-7 hours . But file server of 300 GB
>backup takes 12~14 hours because of number of files are more than 20,000
>
>So far I have come to conclusion that file server backup is slower because
>of no of files are large . But I also have doubt that it is the CPU of
>client which is the bottle neck .
20000 files for 300GB is ~15MB/file IMHO this would not be bottlenecking
on small file size so might be client CPU/disk bottlenecks - run tests
with bigasm (discussed on list) to isolate the problem area.
>Are there any tuning that we can do to make the backup of file server with
>20000 files faster on GB network.
>Will the backup will be faster if you convert the client to direct Storage
>Node ?
not if the client cpu/disk/number of files is the problem, main/only
improvement from DDS is larger i/o bandwidth.
>have Fibre channel card and connected to SAN switch and Tape library on
the
>other side of it.
>
>What is the thumb rule in selecting DSN over normail client .
>Does data size have to be over some value to go for DSN ?
>Ihave to consider that I need to invest DSN license as well as Dynamic
>Drive Sharing License .
>
>Is it too much to consider 12 machines with 1 Terabytes data backing up
over
>GB network with V240 , 2X1GHz CPU 2GB Memory Server having 8 LTO -2
drives
>with SCSI L180 model ?
again use bigasm to test the i/o capability of the networker server, I
know a V880 with 4x900MHz CPUs will keep 8 IBM ultrium-1 drives streaming.
That configuration should allow good utilization of the network as well.
>
>2. Tape Library selection . ( Fibire Channel vs SCSI )
>We are thinking of buying Storage Tek L180 with 8 LTO-2 drives .
>In storage tek we can get two types of models one with Fibre Channel and
one
>with SCSI .
>We will have to take Fibre to SCSI convertor if we go for SCSI model.
>
>For SCSI model there will be 4 SCSI channels with two LTO-2 drives
connected
>to each Channel .
>
>Please correct me if my calculation is wrong .
>
>Ultra160 SCSI speed is 160 mb/s , LTO-2 drive speed is 30 MB /s , we have
>two per channel means 60 mb/s , still well below the limit . ( I can not
>find what SCSI is used in SCSI model of L180 , I need to speak to Storage
>Tek about it . if wide Ultra 2 SCSI 80 mb /s two drives is justified but
>still going for Fibre channel is not justified unless length is issue .)
>In this case I wonder what is the benefit in having Fibre channel
interface
>per drive . When bottle neck is "drive writing speed" which is 30 mb /s
However if (as is usual) you use drive compression then it all depends on
your compression rates. In a simple example we see database compression at
4:1 therefore each drive would be handling 120MB/s and if you could feed
two at this speed then your SCSI would become the bottleneck (of course
with that level one drive streaming would make a 1GB network the
bottleneck). If your fibre to drive chain if all 2GB capable this
shouldn't be a problem unless multiple backups to multiple drives exceeds
the throughput of your fibre "switches".
>
>Same question for the Server , Unless length of the cable isssue , SCSI is
>not a bottle neck when you are using two LTO drives per SCSI channel .
>
>Sorry for asking too many questions in one Email , I don't have any other
>resources to get answers for these questions
>
>best regards,
>Rahul Parasnis
>
As you can see whilst you can make some basic design decisions based on
theoretical values I prefer to see good "real life" testing as there are
so many areas that can trip you up.
--
Note: To sign off this list, send a "signoff networker" command via email
to listserv AT listmail.temple DOT edu or visit the list's Web site at
http://listmail.temple.edu/archives/networker.html where you can
also view and post messages to the list.
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
|
