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[Support #XUY-549936]: LDM Connection Failure -- default rpctimeo ?

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  • Subject: [Support #XUY-549936]: LDM Connection Failure -- default rpctimeo ?
  • Date: Mon, 11 Aug 2008 13:25:25 -0600
Hi Gini,

> I hadn't heard back on this problem yet so I'm just checking if ticket
> still open.
> Thanks
> Gini Galvin

I'm very sorry for not replying sooner.  Your inquiry sat in our inbox
instead of being forwarded to the right person.

We've seen the kind of behavior that you're experiencing: disconnections
for no apparent reason.  David Alden's approach of comparing the LDM
log entries for the same time is the right one.  We've seen many cases
in which a connection breaks and both the upstream LDM and the downstream
LDM can find no underlying cause for the disconnection.  While
disappointing, such behavior is allowed by the underlying TCP
specification.

I seriously doubt that messing with the RPC timeout
parameter will have much effect on this.  If a connection can't be
made in 60 seconds or an RPC response can't be transmitted and
received in 35 seconds, then the network has serious problems.

Is your connection over commercial networks?  If so, then some ISP might
be doing what Comcast has been doing: sending out forged TCP "reset"
packets to artificially close connections that they deem undesirable.

The LDM is designed to pick up a connection where it left off, so you
should loose any data-products providing the mean data rate is less
than the minimum guaranteed one.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: XUY-549936
Department: Support
Priority: Normal
Status: Closed