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Re: NOAAPORT system



Chris,

> From address@hidden Fri Jul  7 10:00:28 2000
> Keywords: 200007071600.e67G0PT01416

> Here's the plan.  We have a 13' (4 m?) satellite dish that we had used
> with a C-band Kavorus data feed.  What we would like to do is use this
> dish as the starting point and add all the equipment needed to give us a
> complete system.

This should work just fine.

> A little ASCII art?
>
>   LNA?
> |------|    wire?            Cat 5 / 100 Mbps?
> | Dish |  --------   Ingest   ------------   Product generator/access
> |------|

This will work just fine -- it's the same as what we have running.

> Please provide any purchase guidance that you can.  Product model,
> vendor, estimated cost if possible.  (I understand that you may not be
> "endorsing" the company.)
>
> Starting at the dish -
>
> 1)  What is the required feed horn?  Is this referred to as a LNA?  Low
> noise amplifier?

You will probably have to re-align the dish and adjust polarity.  You may
be able to reuse the feed horn components.  We did a dish retrofit recently
and had to add a passive signal booster due to cable lengths.  I'm not
current with the terminology, but what was the LNA technology is rolled
into the LNB now -- and that's the extent of the hardware.

> 2)  What are the cable(s) type, specs and (length) limits that will
> connect to the Ingest computer?

This is largely dictated by the length of the cable.  If you are in the
in the proximity of where the Kavorus system was placed, it's likely that
no changes are required, especially since it was C-band too.

> 3)  What is the 4-channel card model number, manufacturer, and other
> purchase info?

We have a Performance Technologies PCI334 PCI card from over a years ago,
but I see a newer PCI344 card that appears to be much better and solves
some of the issues I mentioned in our previous discussion.  I hope to
be able to test the PCI344 card at some point.  See the following website
for more information;

http://www.pt.com/products/index.asp

> 4)  What are the system specs for the computer that serves as the
> ingestor?
>     (disk, memory, cpu, other?)  I think you said it must be Solaris,
> right?
>       Please be sure to consider the added demands of the Radar data in the
> fall!

We're using a dual-CPU Intel 550MHz system with 1GB of RAM and one fast
large 10,000 RPM disk.  We run an LDM on the system and insert data into
the queue (ie no product decoding).  I'd say memory is the most important
item.  I note the newer PCI344 card seems to have Linux support whereas
the PCI334 had only Solaris support.  We can provide more information
on the system, but it's consists of off-the-shelf components we have
custom built here locally.

> 5)  What level of system load will this machine be subjected to?  I
> think that what I'd like to do is not over-spec the ingestor (too much)
> and have a second robust system for product generation, and user
> display.

Our current ingest system is lightly loaded -- and it doesn't seem to
lose data despite the small buffering capabilities of the PCI334 card.
I agree with your design -- we have an identical system doing the
product generation and it's max'ed out on occasion.

>       Or, should I put the product generation on the same system and then
> have a comparable system for user access to the data and products?
>       Or, should we have three systems, one for each service?  (ingest,
> process, access)

Two systems should be adequate.  The key is to keep from losing data on
the ingest system.  We didn't put a lot of time into our system design,
and could possibly run the ingest processes with a real-time priority,
but then the rest of the processing could suffer.  The one area where
our product generation/user access system could be substantially
improved is with hardware RAID.  Right now, we have a 3 x 18GB software
RAID set that is quite busy filing and decoding every data stream that
we have access to.  I'd say moving to the next level with hardware RAID
is very desirable.

> I'm open to any and all thoughts.  I have a bunch of years as a Unix
> administrator, but I have only a limited amount of experience with the
> LDM and these data streams.  (And none with NOAAPORT.)

I think the above discussion hits most of the high points.

> Would it be possible to get a tape of your system that we could dump
> onto our new system?  Making the site specific changes, of course.  Any
> and all assistance in setting the system up would be GREATLY
> appreciated!!!!

Let me check out putting together a tar-file with the required software.
One key difference would be using the newer card which would be a big win
for the on-card buffering improvements and the Linux support.

> In return we could offer another ADDE server to the community (with some
> more help, of course!).  (-:

That would be great!

mike