Chapter 19. Working with HTTP Proxies

Production environments can deny direct access to the Internet and instead have an HTTP or HTTPS proxy available. Configuring OpenShift Enterprise to use these proxies can be as simple as setting standard environment variables in configuration or JSON files. This can be done during an advanced installation or configured after installation.

The proxy configuration must be the same on each host in the cluster. Therefore, when setting up the proxy or modifying it, you must update the files on each OpenShift Enterprise host to the same values. Then, you must restart OpenShift Enterprise services on each host in the cluster.

The NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables are found in each host’s /etc/sysconfig/atomic-openshift-master file (for single master configuration), /etc/sysconfig/atomic-openshift-master-api, or /etc/sysconfig/atomic-openshift-master-controllers files (for multi-master configuration) and /etc/sysconfig/atomic-openshift-node.

The NO_PROXY environment variable lists all of the OpenShift Enterprise components and all IP addresses that are managed by OpenShift Enterprise.

NO_PROXY accepts a comma-separated list of hosts, IP addresses, or IP ranges in CIDR format:

NO_PROXY also includes the SDN network and service IP addresses as found in the master-config.yaml file.

networkConfig:
  clusterNetworkCIDR: 10.1.0.0/16
  serviceNetworkCIDR: 172.30.0.0/16

networkConfig:
  clusterNetworkCIDR: 10.1.0.0/16
  serviceNetworkCIDR: 172.30.0.0/16

OpenShift Enterprise does not accept * as a wildcard attached to a domain suffix. For example, this works:

NO_PROXY=.example.com

NO_PROXY=.example.com

However, this does not:

NO_PROXY=*.example.com

NO_PROXY=*.example.com

The only wildcard NO_PROXY accepts is a single * character, which matches all hosts, and effectively disables the proxy.

Each name in this list is matched as either a domain which contains the host name as a suffix, or the host name itself.

For instance, example.com would match example.com, example.com:80, and www.example.com.

During advanced installations, the NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables can be configured using the openshift_no_proxy, openshift_http_proxy, and openshift_https_proxy parameters, which are configurable in the inventory file.

Global Proxy Configuration
These options configure HTTP_PROXY, HTTPS_PROXY, and NOPROXY environment
variables for docker and master services.
Most environments do not require a proxy between OpenShift masters, nodes, and
etcd hosts. So automatically add those host names to the openshift_no_proxy list.
If all of your hosts share a common domain you may wish to disable this and
specify that domain above.
openshift_generate_no_proxy_hosts=True

# Global Proxy Configuration
# These options configure HTTP_PROXY, HTTPS_PROXY, and NOPROXY environment
# variables for docker and master services.
openshift_http_proxy=http://USER:PASSWORD@IPADDR:PORT
openshift_https_proxy=https://USER:PASSWORD@IPADDR:PORT
openshift_no_proxy='.hosts.example.com,some-host.com'
#
# Most environments do not require a proxy between OpenShift masters, nodes, and
# etcd hosts. So automatically add those host names to the openshift_no_proxy list.
# If all of your hosts share a common domain you may wish to disable this and
# specify that domain above.
# openshift_generate_no_proxy_hosts=True

OpenShift Enterprise node hosts need to perform push and pull operations to Docker registries. If you have a registry that does not need a proxy for nodes to access, include the NO_PROXY parameter with the registry’s host name, the registry service’s IP address, and service name. This blacklists that registry, leaving the external HTTP proxy as the only option.

S2I builds fetch dependencies from various locations. You can use a .s2i/environment file to specify simple shell variables and OpenShift Enterprise will react accordingly when seeing build images.

The following are the supported proxy environment variables with example values:

HTTP_PROXY=http://USERNAME:PASSWORD@10.0.1.1:8080/
HTTPS_PROXY=https://USERNAME:PASSWORD@10.0.0.1:8080/
NO_PROXY=master.hostname.example.com

HTTP_PROXY=http://USERNAME:PASSWORD@10.0.1.1:8080/
HTTPS_PROXY=https://USERNAME:PASSWORD@10.0.0.1:8080/
NO_PROXY=master.hostname.example.com

The example templates available in OpenShift Enterprise by default do not include settings for HTTP proxies. For existing applications based on these templates, modify the source section of the application’s build configuration and add proxy settings:

...
source:
  type: Git
  git:
    uri: https://github.com/openshift/ruby-hello-world
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com
...

...
source:
  type: Git
  git:
    uri: https://github.com/openshift/ruby-hello-world
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com
...

This is similar to the process for using proxies for Git cloning.

You can set the NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables in the templates.spec.containers stanza in a deployment configuration to pass proxy connection information. The same can be done for configuring a Pod’s proxy at runtime:

...
containers:
- env:
  - name: "HTTP_PROXY"
    value: "http://USER:PASSWORD@IPADDR:PORT"
...

...
containers:
- env:
  - name: "HTTP_PROXY"
    value: "http://USER:PASSWORD@IPADDR:PORT"
...

You can also use the oc set env command to update an existing deployment configuration with a new environment variable:

oc set env dc/frontend HTTP_PROXY=http://USER:PASSWORD@IPADDR:PORT

$ oc set env dc/frontend HTTP_PROXY=http://USER:PASSWORD@IPADDR:PORT

If you have a ConfigChange trigger set up in your OpenShift Enterprise instance, the changes happen automatically. Otherwise, manually redeploy your application for the changes to take effect.

If your Git repository can only be accessed using a proxy, you can define the proxy to use in the source section of the BuildConfig. You can configure both a HTTP and HTTPS proxy to use. Both fields are optional.

source:
  type: Git
  git:
    uri: "https://github.com/openshift/ruby-hello-world"
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com

source:
  type: Git
  git:
    uri: "https://github.com/openshift/ruby-hello-world"
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com

Cluster administrators can also configure a global proxy for Git cloning using Ansible.