HAProxy image that balances between linked containers and, if launched in Tutum, reconfigures itself when a linked cluster member joins or leaves
Launch your application container that exposes port 80:
docker run -d --name web1 tutum/hello-world
docker run -d --name web2 tutum/hello-world
Then, run tutum/haproxy
linking it to the target containers:
docker run -d -p 80:80 --link web1:web1 --link web2:web2 tutum/haproxy
The tutum/haproxy
container will listen in port 80 and forward requests to both web1
and web2
backends using a roundrobin
algorithm.
You can overwrite the following HAProxy configuration options:
BACKEND_PORT
(default:80
): The port where the web application backends are listening to.BACKEND_PORTS
(default None): The list of ports(comma separated) where the web application backends are listening to.(On works on Tutum at the moment)FRONTEND_PORT
(default:80
): The port where the load balancer is listening to.MODE
(default:http
): Mode of load balancing for HAProxy. Possible values include:http
,tcp
,health
.HDR
(default:hdr
): "hdr" criteria in acl used in virtualhost. If set tohdr_end
, for instance, haproxy will match all the subdomains'.BALANCE
(default:roundrobin
): Load balancing algorithm to use. Possible values include:roundrobin
,static-rr
,source
,leastconn
.MAXCONN
(default:4096
): Sets the maximum per-process number of concurrent connections.OPTION
(default:redispatch
): Comma-separated list of HAProxyoption
entries to thedefault
section.TIMEOUT
(default:connect 5000,client 50000,server 50000
): Comma-separated list of HAProxytimeout
entries to thedefault
section.SSL_CERT
(default:**None**
): An optional certificate to use on the binded port. It should have both the private and public keys content. If set, port 443 will be used to handle HTTPS requests.SSL_BIND_OPTIONS
(default:no-sslv3
): Optional. Explicitly set which SSL bind options will be used for the SSL server. This sets the HAProxyssl-default-bind-options
configuration setting. The default will allow only TLSv1.0+ to be used on the SSL server.SSL_BIND_CIPHERS
(default:None
): Optional. Explicitly set which SSL ciphers will be used for the SSL server. This sets the HAProxyssl-default-bind-ciphers
configuration setting.VIRTUAL_HOST
(default:**None**
): Optional. Let HAProxy route by domain name. FormatLINK_ALIAS=DOMAIN
, comma separated.STATS_PORT
(default:1936
): Port for the haproxy stats section. If this port is published, stats can be accessed athttp://<host-ip>:<STATS_PORT>/
STATS_AUTH
(default:stats:stats
): Username and password required to access the haproxy stats.
Check the HAProxy configuration manual for more information on the above.
Launch the service you want to load-balance using Tutum.
Then, launch the load balancer. To do this, select "Jumpstarts", "Proxies" and select tutum/haproxy
. During the "Environment variables" step of the wizard, link to the service created earlier (the name of the link is not important), and add "Full Access" API role (this will allow HAProxy to be updated dynamically by querying Tutum's API).
That's it - the proxy container will start querying Tutum's API for an updated list of containers in the service and reconfigure itself automatically.
Use the following:
docker run -d --link webapp:webapp -e BACKEND_PORT=8080 -p 80:80 tutum/haproxy
Use the following:
docker run -d --link webapp:webapp -e FRONTEND_PORT=8080 -p 8080:8080 tutum/haproxy
#### I want the proxy to terminate SSL connections and forward plain HTTP requests to my webapp to port 80
Use the following:
docker run -d --link webapp:webapp -p 443:443 -e SSL_CERT="YOUR_CERT_TEXT" tutum/haproxy
The certificate in YOUR_CERT_TEXT
is a combination of public certificate and private key. Remember to put \n
between each line of the certificate. A way to do this, assuming that your certificate is stored in ~/cert.pem
, is running the following:
docker run -d --link webapp:webapp -p 443:443 -e SSL_CERT="$(awk 1 ORS='\\n' ~/cert.pem)" tutum/haproxy
I want the proxy to terminate SSL connections and forward plain HTTP requests to my webapp to port 8080
Use the following:
docker run -d --link webapp:webapp -p 443:443 -e SSL_CERT="YOUR_CERT_TEXT" -e BACKEND_PORT=8080 tutum/haproxy
Use the following:
docker run -d --link webapp:webapp -p 443:443 -p 80:80 -e SSL_CERT="YOUR_CERT_TEXT" tutum/haproxy
There are two ways to configure virtual hosts with this image.
Method 1: configuring the proxy
Example:
docker run -d --name webapp1 tutum/hello-world
docker run -d --name webapp2 tutum/hello-world
docker run -d --link webapp1:webapp1 --link webapp2:webapp2 -e VIRTUAL_HOST="webapp1=www.webapp1.com, webapp2=www.webapp2.com" -p 80:80 tutum/haproxy
Notice that the format of VIRTUAL_HOST
is LINK_ALIAS=DOMAIN
, where LINK_ALIAS
must match the beginning of the link name and DOMAIN
is the HTTP host that you want the proxy to use to forward requests to that backend.
In the example above, when you access http://www.webapp1.com
, it will show the service running in container webapp1
, and http://www.webapp2.com
will go to container webapp2
.
If you use the following:
docker run -d --name webapp1 tutum/hello-world
docker run -d --name webapp2-1 tutum/hello-world
docker run -d --name webapp2-2 tutum/hello-world
docker run -d --link webapp1:webapp1 --link webapp2-1:webapp2-1 --link webapp2-2:webapp2-2 -e VIRTUAL_HOST="webapp1=www.webapp1.com, webapp2=www.webapp2.com" -p 80:80 tutum/haproxy
When you access http://www.webapp1.com
, it will show the service running in container webapp1
, and http://www.webapp2.com
will go to both containers webapp2-1
and webapp2-2
using round robin (or whatever is configured in BALANCE
).
Method 2: configuring the webapp backends
Alternatively, virtual hosts can be configured by the proxy reading linked container environment variables (VIRTUAL_HOST
). Here is an example:
docker run -d -e VIRTUAL_HOST=www.webapp1.com --name webapp1 tutum/hello-world
docker run -d -e VIRTUAL_HOST=www.webapp2.com --name webapp2 tutum/hello-world
docker run -d --link webapp1:webapp1 --link webapp2:webapp2 -p 80:80 tutum/haproxy
In the example above, when you access http://www.webapp1.com
, it will show the service running in container webapp1
, and http://www.webapp2.com
will go to container webapp2
.
If you use the following:
docker run -d -e VIRTUAL_HOST=www.webapp1.com --name webapp1 tutum/hello-world
docker run -d -e VIRTUAL_HOST=www.webapp2.com --name webapp2-1 tutum/hello-world
docker run -d -e VIRTUAL_HOST=www.webapp2.com --name webapp2-2 tutum/hello-world
docker run -d --link webapp1:webapp1 --link webapp2-1:webapp2-1 --link webapp2-2:webapp2-2 -p 80:80 tutum/haproxy
When you access http://www.webapp1.com
, it will show the service running in container webapp1
, and http://www.webapp2.com
will go to both containers webapp2-1
and webapp2-2
using round robin (or whatever is configured in BALANCE
).
docker run -d -e VIRTUAL_HOST=node.io --name webapp tutum/hello-world
docker run -d --link webapp:webapp -e HDR="hdr_end" -p 80:80 tutum/haproxy
Within Tutum:
|---- container 1
|----- service 1 ----- |---- container 2
| (virtual host 1) |---- container 3
internet --- tutum/haproxy--- |
| |---- container a
|----- service 2 ----- |---- container b
(virtual host 2) |---- container c
Outside Tutum (any Docker server):
|---- container 1 (virtual host 1)
|---- container 2 (virtual host 1)
|---- container 3 (virtual host 1)
internet --- tutum/haproxy--- |
|---- container a (virtual host 2)
|---- container b (virtual host 2)
|---- container c (virtual host 2)