在Linux系统中，Informix数据库本身并不直接给负载均衡功能。负载均衡通常是通过部署外部负载均衡器来实现的。不过Informix能受益于这些个负载均衡器所给的高大可用性和性能提升。

用Nginx作为负载均衡器

1. 安装Nginx

sudo apt-get update
sudo apt-get install nginx

2. 配置Nginx

编辑Nginx的配置文件， 添加以下内容来定义一个负载均衡器：

http {
    upstream informix_servers {
        server 192.168.1.101:9080;
        server 192.168.1.102:9080;
        server 192.168.1.103:9080;
    }
    server {
        listen 80;
        location / {
            proxy_pass http://informix_servers;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
        }
    }
}

3. 沉启Nginx

sudo systemctl restart nginx

用HAProxy作为负载均衡器

1. 安装HAProxy

sudo apt-get update
sudo apt-get install haproxy

2. 配置HAProxy

frontend http_front
    bind *:80
    default_backend servers
backend servers
    balance roundrobin
    server server1 192.168.1.101:9080
    server server2 192.168.1.102:9080
    server server3 192.168.1.103:9080

3. 沉启HAProxy

sudo systemctl restart haproxy

高大可用性配置

1. 用Keepalived配置虚拟IP地址

为了确保高大可用性，能用Keepalived来配置虚拟IP地址，以便在主服务器发生故障时VIP能自动切换到备用服务器。

http {
    upstream informix_servers {
        server 192.168.1.101:9080;
        server 192.168.1.102:9080;
        server 192.168.1.103:9080;
    }
    server {
        listen 80;
        location / {
            proxy_pass http://informix_servers;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
        }
    }
}

2. 沉启Keepalived

sudo systemctl restart keepalived

通过以上步骤，你能在Linux上实现Informix数据库的负载均衡和高大可用性。这些个负载均衡器能有效地将求分发到优良几个Informix服务器上，搞优良系统的吞吐量和可靠性。一边， 用Keepalived能确保在主服务器发生故障时服务能够自动切换到备用服务器，进一步搞优良系统的可用性。