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[LDM #GSH-399207]: Two ldm servers behind a firewall

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  • Subject: [LDM #GSH-399207]: Two ldm servers behind a firewall
  • Date: Tue, 29 Jan 2013 17:34:47 -0700
Hi Harry!

> I have a downstream site I am feeding that has two different machines behind a
> firewall asking my 6.11.2 ldm server for data. Unfortunately my server sees
> these as overlapping requests from the firewall name/IP since they are both
> asking for some of the same data.   They want the two machines requesting the
> data for redundancy in case of a machine failure.  Is there any solution to 
> this
> problem?

By "behind a firewall" I assume you mean that they're behind a NAT router, in 
which case the upstream LDM will think the subscriptions are from the same host.

This is, indeed, a conundrum. That rejection capability is needed to prevent 
accidental DOS attacks.

Probably the easiest workaround would be to enclose the pattern-specifications 
in the REQUEST entries of one of the downstream LDM-s in an extra set of 
parentheses. This way the patterns will compare unequal at the upstream LDM and 
so won't be considered the same subscription.

Bleah! :-)

> --
> Dr. Harry Edmon
> address@hidden, 206-543-0547, FAX: 206-543-0308
> Director of IT, College of the Environment and
> Director of Computing, Dept of Atmospheric Sciences
> University of Washington, Box 351640, Seattle, WA 98195-1640

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: GSH-399207
Department: Support LDM
Priority: Normal
Status: Closed