Hi, That's what I want to discuss about. The paper gives a very detailed explanation on anycast with OSPF_ecmp, and what I want to know is: is there anything not included in it but must be considered carefully when anycast cache server farm is to be established in MAN ? Will there be any problem with OSPF-ECMP convergence ? is there any request with DNS software(BIND, CNS, powerdns etc. ) selection? Considering such a situation, a big ISP want to set up hierachical cache DNS service, it has several MAN interconnected by backbone. each MAN uses a reserved ASN. The backbone has a public ASN and connect to each MAN with e-BGP. Should BGP multipath be considered ? or should each MAN announce same DNS server address block in each e-bgp session ? will there be any possible problem in such situation? what I do care about is, convergence speed, reliablity, load balancing within cache server farm, or load sharing between different cache server farm when one of them failed, cost of administration. Joe
Also, be mindful of ECMP.
http://www.isc.org/pubs/tn/isc-tn-2004-1.html http://www.isc.org/pubs/tn/isc-tn-2004-1.txt
Joe
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