Otdfbt

I am trying to use HAProxy as a load balancer for 2 mysql nodes. I have HAProxy listening on 3307 and it routes requests to the DBs on 3306. When the client is trying to connect to the Proxy (mysql -u ... -h .. -P3307 -p...) it gets the following error:

ERROR 2013 (HY000): Lost connection to MySQL server at 'reading initial communication packet', system >error: 0

When the client is trying to connect directly to the DB it works fine. I have no idea why its failing when traffic goes via the Proxy.

Here's what I've already checked:

1. /etc/hosts.allow includes "mysqld: ALL : allow "




2. MySQL config file (my.cnf) doesn't have a bind address line (open to
   all).

I am using HAProxy 1.5dev, Mysql 5.1.x and the whole enchilada is running in ec2 on Amazon linux.

Here's the HAProxy config file:

 global
 log 127.0.0.1 local0
 log 127.0.0.1 local1 notice
 #log loghost local0 info
 user haproxy
 group haproxy
 maxconn 4096
 daemon
 #debug
 #quiet

 defaults
 log global
 mode tcp
 option tcplog
 option dontlognull
 retries 3
 option redispatch
 maxconn 4096
 contimeout 5000
 clitimeout 50000
 srvtimeout 50000

 frontend mysql_cluster
 bind 10.0.0.150:3307
 default_backend mysql_cluster

 backend mysql_cluster
 mode tcp
 balance roundrobin
 option tcpka
 option httpchk
 server lb1 10.0.0.140:3306 check port 9200 inter 5s rise 2 fall 2
 server lb2 10.0.0.214:3306 check port 9200 inter 5s rise 2 fall 2 

 listen stats 10.0.0.150:8081
 mode http
 option httpclose
 balance roundrobin
 stats uri /
 stats realm Haproxy Statistics
 stats auth ***:***

Has anyone tackled this problem before? Any ideas how to solve this?

Any help much appreciated

OK, I solved it. I had a problem with my xinetd script.

It failed to bind on 9200 - fixed it in /etc/services file.

It usually occurs when your xinetd health check service responses error.

you can debug xinetd by telnet like this:

telnet IPADDR PORT # IPADDR: one of the IPs of your nodes
 # PORT: the port that node is listening.

the output tells you about the problem.

On my setup, I wasnt running xinetd, but found that the mysql-check option was causing issues. So I was at least able to get haproxy up and running by commenting it out. I suspect that mysql-check has something to do with either wrong mysql user being used or missing grants.

Thanks dear , great,

HAproxy need xinetd to be configured properly to work else below error appears ,

ERROR 2013 (HY000): Lost connection to MySQL server at 'reading initial communication packet', system error: 0

Xinetd to be restated if running already .

https://docs.openstack.org/ha-guide/shared-database-manage.html