Three-tier routing high availability refers to the high availability of routing in the Network layer in the network protocol model. Implemented based on virtual IP. The corresponding four layer transport layer LVS is implemented via IP and port. The seven-tier application layer F5 can be implemented via URLs.
Scene:
3 Linux servers, 2 servers deployed services, 1 remaining as application client
Realize:
In3ConsoleLinuxAll deployments on the serverBGPServices, will3Machine planning to the sameBGPArea, therebyImplement LetClientability to dynamically learn routing tables. In the2DeskServer, configure a10.100.1.1thisIP,Clientthrough10.100.1.1thisIPaccess to services, usuallyAThe service is responsible for handlingClientthe request,ClientonThe routing table is the10.100.1.1the data is sent toAserver, whenAwhen there is a problem with the server,ClientIt will be dynamicupdate your own routing table to update the routing table toBon the server. For high Availability
Analytical:
Server-side a:192.168.1.3/b:192.168.1.4 are manually set the virtual loopback IP for the 10.0.0.1,client side C through the BGP learning, will generate a routing table based on the shortest path algorithm to select the path of a more optimal service-side address assume a more excellent New route Table 10.0.0.1--192.168.1.3. In the process of use, the BGP network will continue to send each other keeplive packets if C to send a packet result of failure is a down, then C will delete the route table 10.0.0.1--192.168.1.3. and re-learning the new routing table 10.0.0.1-192.168.1.4 allows C to select hot standby server B for data interaction in case of server a downtime, to avoid problems caused by a downtime.
Highly available methods based on three-tier routing BGP (Border Gateway Protocol)