Questions tagged [anycast]

For questions about Anycast, where it is a network addressing and routing method in which datagrams from a single sender are routed to any one of several destination nodes, selected on the basis of which is the nearest, lowest cost, healthiest, with the least congested route, or some other distance measure.

Filter by
Sorted by
Tagged with
0
votes
3answers
46 views

Does Anycast allow any low-level destination control?

As an experiment, I'd like to get responses from a few different 8.8.8.8 servers (per anycast, multiple physical machines are grouped as one IP address, and I believe inspection of the request/...
3
votes
1answer
62 views

What are usecases for IPv6 link-scope anycast?

IPv6 Neighbor Advertisement messages have a flag called Override, see RFC4861. It toggles, whether the receiver of the message should remove other link-layer addresses for the same IPv6 target address ...
2
votes
2answers
72 views

What are some high-traffic websites that operate with a global anycast IP address?

I've been trying to find an example of an anycast IP address used by a hugely popular service or a website. According to my queries at https://www.whatsmydns.net/ , none of the large sites that are ...
1
vote
2answers
52 views

How TCP connections between origin and node servers over a BGP Anycast gets established?

Server A and B have the same IP address with anycast. Server B connects to the origin server that is very close to server A and very far away from server B, since server A is closer, the response will ...
9
votes
2answers
1k views

Does anycast addressing add additional latency in any way?

Does anycast addressing, in itself, add any additional latency to network connections? Specifically, if you had two servers located in the same data center that had extremely similar routes/number of ...
1
vote
1answer
39 views

Whether the anycast nodes can not in the same AS, and whether the different AS can pronounce the same IP segment?

The Anycast realize is through annunciate the same IP address in the different node using BGP protocol. you see the Server A and Server B use the BGP annunciate the same IP address 10.0.0.1. There ...
2
votes
1answer
164 views

how to select the most optimized BGP Anycast combination with BGP as-path prepending

The question as following: Suppose I have 3 POP (Points of Presence) points, they have the same IP address and located at different countries, such as: USA, Japan, England. The three countries serve ...
1
vote
1answer
462 views

Lab - IPv4 anycast vlan and host interactions for OSPF

I am trying to wrap my head around anycast on ipv4 and then ipv6. I am trying to figure out how to properly setup anycast on a multilayer switch and haven't found any good documentation on how it ...
10
votes
4answers
2k views

Using IP subnet at multiple datacenters

We control IPv4 and IPv6 subnets. Now we'd like to use a part of a /24 IPv4 subnet at one datacenter and another part at another datacenter. I know that announcing the subnet on the internet at ...
5
votes
2answers
611 views

How is anycast implemented?

According to this answer Google DNS (8.8.8.8) has low worldwide latencies because it uses anycast. How is anycast actually implemented? That is, how does a packet get routed to different computers ...
0
votes
2answers
113 views

Is DNS geo-redundant if my traceroute to each NS shows the same location?

Some providers employ BGP anycast for their NS servers. As a user, when doing a traceroute, many may show an identical location for both servers, for a given client. When he.net used to anycast ...
4
votes
2answers
265 views

How does anycast ensure reliable delivery of IP packets for the same IP address on different locations?

With anycast, it would be possible to have the same IP address at multiple locations in the world, without the need of a proxy or VPN that forwards the packets to its final destination. If you would ...
2
votes
2answers
1k views

Preferred anycast paths for DNS with Quagga BGP

Background and goal Am setting up high availability DNS servers based on Unbound. Both DNS servers has in reality twelve BGP sessions against different routers but to make this easier only one router ...
2
votes
1answer
61 views

Anycasted Service responding from regular IP address

Trying to set up an anycast DNS setup. For the time being, we have two routers, R01 and our Mgmt router that we're using until we move to SDN (in testing phases). The problem we're having is the DNS ...
2
votes
1answer
743 views

IPv6 Testing Addressing Type Confusions

I'm new in the IPv6 Topic and Yesterday I was performing some testing on Cisco IOS and Cisco Routers of the addressing type in IPv6 with RIPng, i was testing the following: Global Unicast Address ...
2
votes
1answer
664 views

Is it possible to set up (geographic) anycast on the Internet?

The top level DNS-servers use geographic anycast. Is it possible to set up geographic anycast on your own (DNS) servers on the Internet? The top level DNS-servers use geographic anycast. Is this set ...
16
votes
4answers
5k views

Why does this router fail to use multiple, equal-cost routes from OSPF?

A Brocade router running NetIron 5.2, and a Dynamips emulation running IOS 12.4 both fail to dependably use equal cost paths in what seems to be a very simple configuration. I say "dependably" because ...