CODEWITHSUNDEEP
ubuntumariadbload-balancinghaproxy
Emrah Tema
Emrah Tema

Reputation: 365

Is there any HAProxy load balancing algorithm that routes connections to only one server?

I have three servers(MariaDB services) and one HAProxy server on front of them and the HAProxy distributes connections to these servers with roundrobin. But I want that the HAProxy server must route all connections to server1. If server1 is unreachable, it must route to the server2.. Is there any load balancing algorithm that makes it possible?

Upvotes: 1

Views: 1621

Answers (1)

nbari
nbari

Reputation: 26925

What probably you are looking for is for a failover/backup configuration, check more details here (https://www.haproxy.com/blog/failover-and-worst-case-management-with-haproxy/), this is a basic example:

backend mysql
    mode tcp
    balance leastconn
    server s1 10.0.0.1:3306 check 
    server s2 10.0.0.2:3306 check backup
    server s3 10.0.0.3:3306 check backup

From the HAProxy docs:

backup

When "backup" is present on a server line, the server is only used in load balancing when all other non-backup servers are unavailable. Requests coming with a persistence cookie referencing the server will always be served though. By default, only the first operational backup server is used, unless the "allbackups" option is set in the backend. See also the "no-backup" and "allbackups" options.

In case your servers belong to a galera cluster something you could try httpwsrep:

backend mysql
    mode tcp
    option httpchk
    default-server check port 9200
    server s1 10.0.0.1:3306 
    server s2 10.0.0.2:3306
    server s3 10.0.0.3:3306

Upvotes: 3

Related Questions