Re: interop problems with getaddrinfo() address selection
Tony Finch <dot@dotat.at> Mon, 10 December 2007 07:50 UTC
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Date: Mon, 10 Dec 2007 07:49:52 +0000
From: Tony Finch <dot@dotat.at>
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To: Keith Moore <moore@cs.utk.edu>
Subject: Re: interop problems with getaddrinfo() address selection
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References: <Pine.LNX.4.64.0712061901020.24448@hermes-1.csi.cam.ac.uk> <200712062020.PAA16213@Sparkle.Rodents.Montreal.QC.CA> <Pine.LNX.4.64.0712071735070.24448@hermes-1.csi.cam.ac.uk> <475B0ABC.5090806@cs.utk.edu> <Pine.LNX.4.64.0712092000150.29087@hermes-1.csi.cam.ac.uk> <475C5047.3010807@cs.utk.edu>
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Cc: der Mouse <mouse@Rodents.Montreal.QC.CA>, discuss@apps.ietf.org
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On Sun, 9 Dec 2007, Keith Moore wrote: > > I think it's a stretch to assume that in the future that all IP > addresses associated with a domain and advertised in DNS are equally > reachable. The examples you listed, based on different kinds of connectivity, are reasonable; what it not is de-randomizing equivalent classes of address. > What causes the problem is the assumption that a destination can have > multiple addresses, a source can have multiple addresses, and the party > initiating the connection can somehow make a good decision about which > address pair to use without any information from the network. Yes :-) > As for DNS randomization, it's never been reasonable to expect an > application to try each of several addresses in the order returned by > DNS. That has been the de facto standard behaviour for over 10 years (though before getaddrinfo they only tried the first). A lot of sites are going to be rather upset if wide deployment of RFC 3484 suddenly breaks their service architecture. Tony. -- f.a.n.finch <dot@dotat.at> http://dotat.at/ DOVER: NORTHWESTERLY 6 TO GALE 8, DECREASING 4 LATER. MODERATE OR ROUGH, OCCASIONALLY VERY ROUGH. SQUALLY SHOWERS. GOOD.
- interop problems with getaddrinfo() address selec… Tony Finch
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… Stephane Bortzmeyer
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… Keith Moore
- Re: interop problems with getaddrinfo() address s… der Mouse
- Re: interop problems with getaddrinfo() address s… Tony Finch
- Re: interop problems with getaddrinfo() address s… Keith Moore