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[LDM #OEP-635687]: question about primary and secondary data transfer

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  • Subject: [LDM #OEP-635687]: question about primary and secondary data transfer
  • Date: Fri, 12 Jan 2018 14:55:02 -0700
Greg,

> I can ask that. I'll send them an email.
> 
> In the meantime, I checked the ldm log file. Our local is showing "is willing 
> to be a primary feeder" and the remote alternate is showing " willing to be 
> an alternate feeder".
> 
> But I do see a lot of flapping... bouncing between "Switching data-product 
> transfer-mode to primary" and "Switching data-product transfer-mode to 
> alternate" for the remote server.

Ah!

> What are the circumstances that cause the transfer mode to shift,

IF, after one minute, a downstream LDM process in ALTERNATE mode discovers that 
its inserting most of the data products into the queue, then it will disconnect 
and reconnect in PRIMARY mode. The reverse is true for a downstream process in 
PRIMARY mode.

> and is that tunable?

No.

> Our primary has been up the whole time.

Doesn't matter. It's a question of when the data-products arrive.

It's likely that the total bandwidth necessary to deliver all products is being 
split between your two upstream sites -- with very little overhead or 
duplication of products.

Let them switch. Computers are good that that sort of (repetitive) thing. :-)

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: OEP-635687
Department: Support LDM
Priority: Normal
Status: Closed
===================
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