Haproxy中基于客户端IP的动态后端选择

Question

我想选择一个基于自定义散列函数的后端，它会散列客户机ip (我知道这并不理想，但我正在尝试这种方法)。

伪配置看起来像，

frontend myserver
    bind *:80 
    acl  MyHash(clientIP) %2 
    use_backend backend0 if {MyHash(clientIP)%2 -m int 0}
    default_backend backend1

backend backend0
    balance leastconn
    server server-1 <ip>:port check 
    server server-2 <ip>:port check 

backend backend1
    balance leastconn
    server server-3 <ip>:port check 
    server server-4 <ip>:port check 

我之所以这样做而不是下面的备选方案，是因为我不想一直将客户端连接到服务器，而是在属于同一集群的服务器之间分配负载。服务器-1-2组成一个集群，服务器-3-4也是如此.

frontend myserver
    bind *:80 
    default_backend mybackend



backend mybackend
    balance source
    hash-type consistent 
    server server-1 <ip>:port check 
    server server-2 <ip>:port check 
    server server-3 <ip>:port check 
    server server-4 <ip>:port check

Answer 1

才能解决这个问题。

frontend myserver
    bind *:80 
    acl select_backend_0 src,field(-1,.),mod(2) -m int 0 
    acl select_backend_1 src,field(-1,.),mod(2) -m int 1
    # Use section can be further optimized, like using a map or something.
    use_backend backend0 if select_backend_0
    use_backend backend1 if select_backend_1
    

backend backend0
    balance leastconn
    server server-1 <ip>:port check 
    server server-2 <ip>:port check 

backend backend1
    balance leastconn
    server server-3 <ip>:port check 
    server server-4 <ip>:port check