Working with HTTP Proxies

Overview

Production environments can deny direct access to the Internet and instead have an HTTP or HTTPS proxy available. Configuring OKD to use these proxies can be as simple as setting standard environment variables in configuration or JSON files. This can be done during an cluster 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 OKD host to the same values. Then, you must restart OKD services on each host in the cluster.

The NO_PROXY, HTTP_PROXY, and HTTPS_PROXY environment variables are found in each host’s /etc/origin/master/master.env and /etc/sysconfig/atomic-openshift-node files.

Configuring NO_PROXY

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

On the OpenShift service accepting the CIDR, NO_PROXY accepts a comma-separated list of hosts, IP addresses, or IP ranges in CIDR format:

For master hosts

• Node host name

• Master IP or host name

• IP address of etcd hosts

For node hosts

• Master IP or host name

For the Docker service

• Registry service IP and host name

• Registry service URL docker-registry.default.svc.cluster.local

• Registry route host name (if created)

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

/etc/origin/master/master-config.yaml

networkConfig:
  clusterNetworks:
  - cidr: 10.1.0.0/16
    hostSubnetLength: 9
  serviceNetworkCIDR: 172.30.0.0/16

OKD does not accept * as a wildcard attached to a domain suffix. For example, the following would be accepted:

NO_PROXY=.example.com

However, the following would not be:

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.

Configuring Hosts for Proxies

1. Edit the proxy environment variables in the OKD control files. Ensure all of the files in the cluster are correct.

   HTTP_PROXY=http://<user>:<password>@<ip_addr>:<port>/
   HTTPS_PROXY=https://<user>:<password>@<ip_addr>:<port>/
   NO_PROXY=master.hostname.example.com,10.1.0.0/16,172.30.0.0/16 (1)

   1	Supports host names and CIDRs. Must include the SDN network and service IP ranges 10.1.0.0/16,172.30.0.0/16 by default.

2. Restart the master or node host:

   # master-restart api
   # master-restart controllers
   # systemctl restart atomic-openshift-node

Configuring Hosts for Proxies Using Ansible

During cluster 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.

Example Proxy Configuration with Ansible

# 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>@<ip_addr>:<port>
openshift_https_proxy=https://<user>:<password>@<ip_addr>:<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

Proxying Docker Pull

OKD 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

• the service name.

This blacklists that registry, leaving the external HTTP proxy as the only option.

1. Retrieve the registry service’s IP address docker_registy_ip by running:

   $ oc describe svc/docker-registry -n default
   Name:            docker-registry
   Namespace:        default
   Labels:            docker-registry=default
   Selector:        docker-registry=default
   Type:            ClusterIP
   IP:            172.30.163.183 (1)
   Port:            5000-tcp    5000/TCP
   Endpoints:        10.1.0.40:5000
   Session Affinity:    ClientIP
   No events.

   1	Registry service IP.

2. Edit the /etc/sysconfig/docker file and add the NO_PROXY variables in shell format, replacing <docker_registry_ip> with the IP address from the previous step.

   HTTP_PROXY=http://<user>:<password>@<ip_addr>:<port>/
   HTTPS_PROXY=https://<user>:<password>@<ip_addr>:<port>/
   NO_PROXY=master.hostname.example.com,<docker_registry_ip>,docker-registry.default.svc.cluster.local

3. Restart the Docker service:

   # systemctl restart docker

Using Maven Behind a Proxy

Using Maven with proxies requires using the HTTP_PROXY_NONPROXYHOSTS variable.

See the Red Hat JBoss Enterprise Application Platform for OpenShift documentation for information about configuring your OKD environment for Red Hat JBoss Enterprise Application Platform, including the step for setting up Maven behind a proxy.

Configuring S2I Builds for Proxies

S2I builds fetch dependencies from various locations. You can use a .s2i/environment file to specify simple shell variables and OKD 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

Configuring Default Templates for Proxies

The example templates available in OKD 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
    noProxy: somedomain.com, otherdomain.com
...

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

Setting Proxy Environment Variables in Pods

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>@<ip_addr>:<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>@<ip_addr>:<port>

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

Git Repository Access

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. Domains for which no proxying should be performed can also be specified via the NoProxy field.

source:
  git:
    uri: "https://github.com/openshift/ruby-hello-world"
    httpProxy: http://proxy.example.com
    httpsProxy: https://proxy.example.com
    noProxy: somedomain.com, otherdomain.com