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ZigzagAK / ngx_dynamic_upstream

Dynamic upstream for nginx
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Ketama hash support #3

Closed Perlovka closed 6 years ago

Perlovka commented 6 years ago

When upstream is defined with hash consistent, upstream server will be added via HTTP API, but will not receive traffic.

Example config:

upstream test {
    hash $arg_hash consistent;
    keepalive 16;
    zone test_upstream 10m;

    server 10.1.5.250 weight=100;
}
ZigzagAK commented 6 years ago

@Perlovka It is not possible to implement because internal structure for hased upstream declared in ngx_http_upstream_hash_module.c. This is an internal feature of the hash upstream module. In custom upstream modules we have access only to ngx_http_upstream_rr_peer_t. But for hash nginx declare separate internal structure: typedef struct { / the round robin data must be first / ngx_http_upstream_rr_peer_data_t rrp; ngx_http_upstream_hash_srv_conf_t *conf; ngx_str_t key; ngx_uint_t tries; ngx_uint_t rehash; uint32_t hash; ngx_event_get_peer_pt get_rr_peer; } ngx_http_upstream_hash_peer_data_t;

We don't have access to this structure.

More: dynamicaly add/remove peers from hashed upstream corrupts the memory.

You may write custom balancer with lua-nginx-module by balancer_by_lua_block.