Для понима как добата табли с уда агents, важно first иметь базовое understanding о distributed tables In this article, we will focus на как использовать distributed table как basis для созда кластер Мanticore instances.
Here is example как split data over 4 servers, each serving one of shards:
- ini
table mydist {
type = distributed
agent = box1:9312:shard1
agent = box2:9312:shard2
agent = box3:9312:shard3
agent = box4:9312:shard4
}In event server failure, distributed table will still work, but results from failed shard will be missing.
Now that we've added mirrors, each shard is found on 2 servers. By default, master (searchd instance with distributed table) will randomly pick one of mirrors.
Mode used for picking mirrors can be set using ha_strategy setting. In addition to default random mode there's also ha_strategy = roundrobin.
More advanced strategies based on latency-weighted probabilities include noerrors and nodeads. These not only take out mirrors with issues but also monitor response times and do balancing. If mirror responds slower (for example, due to some operations running on it), it will receive fewer requests. When mirror recovers and provides better times, it will receive more requests.
- ini
table mydist {
type = distributed
agent = box1:9312|box5:9312:shard1
agent = box2:9312:|box6:9312:shard2
agent = box3:9312:|box7:9312:shard3
agent = box4:9312:|box8:9312:shard4
}