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[LDM #OQD-608743]: ldm failover question

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  • Subject: [LDM #OQD-608743]: ldm failover question
  • Date: Tue, 27 Oct 2009 14:59:45 -0600
Sue,

> Can you confirm that what follows is true:
> If you have two servers making products with identical ids,
> a requesting server could request from both product
> producing servers and only one product of unique ID would
> make it into the queue from the producing servers
> So this could provide a failover mechanism for system products.

The two upstream sites would have to ensure that the data-product signatures 
(i.e., MD5 checksums) were computed identically.  Also, the data-products would 
have to have the same feedtype as well as the same product-identifier.

> If it works as above, Can you define one machine to be the
> "failover" or do products just compete to get into the queue
> on a product by product basis.

Both upstream sites would compete to send data-products to the downstream site. 
 One of the upstream sites would be in PRIMARY mode and the other would be in 
ALTERNATE mode.  The downstream site would switch modes between them based on 
which upstream site was better able to feed it.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: OQD-608743
Department: Support LDM
Priority: Normal
Status: Closed