How to monitor HAProxy

haproxy

We have two HAProxy servers using keapalived for failover. Once one goes down, the other one takes over seamlessly.

I know it is possible to configure HAProxy to send an email to alert a sysadmin, but it would also be helpful to see the health n the HAProxy statistics page where all monitored services are displayed. (hostname:1936/?stats).

Is this possible? Currently we don't even know which one of the servers is serving the stats page.

Best Answer

If all you want to know is which node is the active one, then look at using the stats show-node directive.

Add it to your stats section and you're good to go.

Related Solutions

HAproxy + failover on same nodes as apache

HAProxy doesn't care if the web servers are on the local machine. Adding Apache to the same machine and using different ports is perfectly valid. Some day you may want to dedicate HAProxy but you probably don't need to yet (HAProxy has very low resource usage for Stack Overflow Currently).

Another option besides the multiple ports would be to have multiple IPs on each machine and bind to those. You can bind to a:

wildcard ip and a specific port
wildcard port and a specific ip
wildcard port and wildcard ip
specific ip and specific port

Also to bind to a specific VIP (Virtual failover IP) you will want the following in /etc/sysctl.conf:

net.ipv4.ip_nonlocal_bind=1

Haproxy: adding tcplog parameters

My current answer/solution (mentioned in the question) is as follows.

I define a different 'listen' for each port to be bound with a recognisable name.

I then ensure option tcplog is enabled for that frontend.

The logging then provides me the two pieces of information I need. The frontend and backend used.

e.g.

haproxy[18989]: 127.0.0.1:34550 [15/Oct/2003:15:24:28.312] frontend backend/server 0/0/5007 0 cD 0/0/0/0/0 0/0

I parse that log file 'magically' and use that information to present the latest status.

option logasap helps..

Best Answer

Related Solutions

HAproxy + failover on same nodes as apache

Haproxy: adding tcplog parameters

Related Topic