(no subject)

[Neil Brown]

Subject: Re: Routing problem with udp, and a multihomed host in 2.4.20
In-Reply-To: message from Herbert Xu on Saturday February 15
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On Saturday February 15, [e-mail] wrote:
> Neil Brown <[e-mail]> wrote:
> > 
> > It turns out that the problem occurs when send_msg is used to send a
> > UDP packet, and the control information contains
> >              struct in_pktinfo {
> >                  unsigned int   ipi_ifindex;  /* Interface index */
> >                  struct in_addr ipi_spec_dst; /* Local address */
> >                  struct in_addr ipi_addr;     /* Header Destination address */
> >              };
> > specifying the address and interface of the message that we are
> > replying to.
> 
> So your application is forcing the packet to go out on a specific
> interface bypassing the routing table...

No.
My application (which is just using standard rpc server libraries) is
saying
  "This is in reply to a request that came in through a given
  interface".

It is not reasonable to treat that statement as equivalent to:
  "This packet must go out that interface"

which is what appears to be happening.

NeilBrown

> -- 
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> Email:  Herbert Xu ~{PmV>HI~} <[e-mail]>
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