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-1
votes
0answers
15 views

What is the difference between Multihoming and IP Anycast? [closed]

I was wondering what is the difference between Multihoming and IP Anycast, if any. Furthermore, would it be possible to do Multihoming/IP Anycast with an assigned block of Provider-Aggregatable IPs ...
-4
votes
1answer
46 views

Do anycast addresses imply IPv6? [closed]

From what I understand, as a random user on the Internet, you cannot really know if an IPv4 address is unicast or anycast. However if you ping that IPv4 from two hosts physically located on two ...
3
votes
1answer
62 views

What interaction is required for a Windows server and Cisco router to setup and destroy a Multicast session?

I'm trying to understand how Multicast actually works, and have read numerous articles and Wiki pages, and have gathered this: A multicast address takes up state on the router of the membership, ...
0
votes
3answers
103 views

How does anycast work with tcp?

TCP, being stateful, should require subsequent packets to reach the same server. (Stateless) HTTP runs on top of TCP, and CDN's can use anycast. So how does TCP work with anycast? What if the syn ...
2
votes
2answers
147 views

ip route get recognizes address as anycast

# ip route get 1.2.3.4 anycast 1.2.3.4 dev eth0 src 5.6.7.8 and the question is how does it know the address is an anycast ? (which apparently is true). UPDATED: Present as anycast route: ...
6
votes
3answers
749 views

DNS servers already use anycast. Will adding more IPs enhance scalability?

RFC 1034 requires us to assign at least two IP addresses for DNS servers. However, redundancy can already be achieved by a single IP address if we use anycast addressing. BGP anycast seems to scale ...
0
votes
2answers
180 views

How to determine IP address is unicast or anycast? [closed]

I searched the Internet and unable to find an answer. Anyone can help?
1
vote
0answers
110 views

Why an anycast server is so far away / slow? How does BGP anycast work?

I've tried doing a couple of traceroute tests to the DNS servers of Rage4, which are anycasted from many parts of the world (supposedly, from 30 different locations). What I've experienced is that ...
1
vote
1answer
32 views

Distributed webservice, geolocalized access

I wish I could deploy a very low network latency webservice (running Linux). I was thinking about distributing some instances amongst several dedicated servers (eventually VMs, but not the preferred ...
4
votes
1answer
86 views

Anycast network - steps required to implement one?

As part of our cloud-based security service, we have a DNS server deployed in the cloud. Instead of providing different IPs to customers in different geo-locations, we want to use a unified Anycast ...
0
votes
2answers
85 views

Geographical proximity based IP translation

I'm currently using Amazon's EC2 for my socket application to which mobile devices connect via an application I've written (it uses the server's IP address to connect). I'm looking for a Load ...
1
vote
1answer
32 views

What is an anycast with controlled access

I'm interested in how anycast works. There are two ways how a transmitter sends a packet to the receiver. I'm interested in how anycast with controlled access works. How a destination host is chosen. ...
3
votes
2answers
482 views

Anycast DNS — how do you deal with TCP DNS requests?

Let's assume I have setup a pair of anycasted DNS servers on my internal network using bird and they're just talking OSPF to my core routers. I've found this on the internet and made it happen. If I ...
3
votes
3answers
943 views

Practical Anycast

I've read How can I send visitors to the closest server using DNS? post, but there's still some thing, on a practical level that I don't understand. Say I have two servers. One in NY another in ...
1
vote
2answers
417 views

Transparent geographical DR website failover

We've already got webservers that are loadbalanced. And even though outages shouldn't happen, they do, for a variety of reasons. (central switch failure, misconfigured ISP routers, backbone failures, ...
3
votes
1answer
155 views

How to find out the location of Google IP number: e.g. 209.85.143.94

I am building DNS service and I need to find out location of DNS servers querying me. Apparently anyone who is using Google public DNS like 8.8.8.8 is coming from Google /17 network, and if I do geoip ...
2
votes
1answer
126 views

Traceroute (tracert) anycast address on Windows strange behavior

Tracing route to d.resolvers.level3.net [4.2.2.4] over a maximum of 30 hops: 1 25 ms 27 ms 26 ms d.resolvers.level3.net [4.2.2.4] Trace complete. Tracing route to ...
0
votes
1answer
363 views

Will anycast helps me in my case and how to implement it?

I have several servers with different IPs, deployed in different datacenters (mostly geographically close to our users). Let's imagine that this is simple web servers. What I'd like to have is a ...
2
votes
1answer
131 views

DNS servers via RA in IPv6

Some time ago, RFC 6106 was created, which states how a router tells the clients about the DNS server to be used. It is a new standard, it has to be implemented, which needs time etc. I'm courious ...
7
votes
3answers
4k views

What is the difference between Anycast and GeoDNS / GeoIP wrt HA?

Based on the Wikipedia description of Anycast, it includes both the distribution of a domain-name-to-many-IP-mapping across many DNS servers as well as replying to clients with the most geographically ...
0
votes
2answers
252 views

How to geolocate a server using an anycast ip?

Usually an anycast ip can be located say in the US, but the server itself thats sending the request is located in Europe. I'm wondering if there's anyway of finding out where the server is located.
29
votes
3answers
30k views

What is the difference between unicast, anycast, broadcast and multicast traffic?

I have never had the privilege of working in an environment that required complicated routing or if it did require it, it was handled upstream of me. I've always used very simple static routing ...
6
votes
1answer
575 views

Is there a way to set up Avahi to implement “anycast name resolution” on a LAN?

First, some background: We've got a lab containing a handful of dedicated Linux servers that run on an isolated LAN. All the servers run the same OS (Debian Linux) and the same proprietary server ...
9
votes
3answers
4k views

What is needed to use anycast IPs?

So, there're a bunch of questions on SF about the uses and how anycast IPs are cool. My approach is something more practical. What specifically I need to have to use one of those addresses? Do I ...
0
votes
1answer
111 views

Scanning or identifying anycast IPs

I'm trying to find a way of "identifying" anycast IPs. This turns out to be rather tricky, as it's (usually) dependant on BGP routes directing you to the nearest available host. What are common ...
2
votes
2answers
310 views

DNS Resolver Speed Techniques

I recently received a reply to my concerns about some DNS servers being slower than others despite all servers being anycast: In practice, most resolvers won't be impacted by the slower paths to ...
1
vote
1answer
147 views

Is it possible to determine how may servers is connected to an anycast address?

It's possible to set up several servers with the same IP-address, on the internet, using anycast address. Using routing protocols , the server geographical closest to you responds to queries. I ...
3
votes
3answers
869 views

Simple Anycast Howto?

some DNS providers give me anycast, like: http://web.easydns.com/DNS_hosting.php Now what do i do to get it working? 1. Buy "DNS Hosting package" from them 2. Have some servers with the same IP ...
0
votes
1answer
126 views

Is this anycast behaviour correct?

When connecting to an service provided using anycast, I am experiencing different behaviour depending on whether the request is made using TCP or UDP. With TCP, the request is made to address A, and ...
30
votes
9answers
2k views

What's the piece of hardware listening on Facebook's or Wikipedia's IP address?

I am trying to understand how massive sites like Facebook or Wikipedia work, for my intellectual curiosity. I read about various techniques for building scalable sites, but I am still puzzled about ...
1
vote
1answer
867 views

N-way DHCP redundancy with ISC dhcpd and anycast ip helpers

We're implementing a new IPAM solution across all our campuses and are using bind with anycast to provide 8-way resiliency for all our DNS servers. I would like to be able to do the same with our ...
51
votes
11answers
14k views

Multiple data centers and HTTP traffic: DNS Round Robin is the ONLY way to assure instant fail-over?

Multiple A records pointing to the same domain seem to be used almost exclusively to implement DNS Round Robin as a cheap load balancing technique. The usual warning against DNS RR is that it is not ...
33
votes
7answers
18k views

What is “anycast” and how is it helpful?

I'd never heard of anycast until a few seconds ago when I read this SF post. The wikipedia entry on it is quite formal and doesn't really evoke a mental picture of how it would be used. Can someone ...