Chapter 2. Platform Administration
This chapter covers tasks related to the various OpenShift Enterprise platform components on broker and node hosts.
2.1. Changing the Front-end HTTP Configuration for Existing Deployments
Starting with OpenShift Enterprise 2.2, the Apache
Virtual Hosts front-end HTTP proxy is the default for new deployments. If your nodes are currently using the previous default, the Apache mod_rewrite plug-in, you can use the following procedure to change the front-end configuration of your existing deployment.
Configuring the HTTP front-end for an already-deployed OpenShift Enterprise instance after it has been configured is possible, but Red Hat
recommends caution when doing so. You must first prevent any front-end changes made by the broker, such as creating or deleting application gears, on the node host containing the applications during this configuration change. Performing a verified backup of the node host before commencing configuration is highly recommended.
See the OpenShift Enterprise Deployment Guide for more information about installing and configuring front-end
HTTP server plug-ins.
Procedure 2.1. To Change the Front-end HTTP Configuration on an Existing Deployment:
- To prevent the broker from making any changes to the front-end during this procedure, stop the ruby193-mcollective service on the node host:
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Then set the following environment variable to prevent each front-end change from restarting the httpd service:service ruby193-mcollective stop#
export APACHE_HTTPD_DO_NOT_RELOAD=1 - Back up the existing front-end configuration. You will use this backup to restore the complete state of the front end after the process is complete. Replace filename with your desired backup storage location:
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oo-frontend-plugin-modify --save > filename - Delete the existing front-end configuration:
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oo-frontend-plugin-modify --delete - Remove and install the front-end plug-in packages as necessary:
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yum remove rubygem-openshift-origin-frontend-apache-mod-rewrite#yum -y install rubygem-openshift-origin-frontend-apache-vhost - Replicate any Apache customizations reliant on the old plug-in onto the new plug-in, then restart the httpd service:
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service httpd restart - Change the
OPENSHIFT_FRONTEND_HTTP_PLUGINSvalue in the/etc/openshift/node.conffile fromopenshift-origin-frontend-apache-mod-rewritetoopenshift-origin-frontend-apache-vhost:OPENSHIFT_FRONTEND_HTTP_PLUGINS="openshift-origin-frontend-apache-vhost"
- Un-set the previous environment variable to restarting the httpd service as normal after any front-end changes:
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export APACHE_HTTPD_DO_NOT_RELOAD="" - Restart the MCollective service:
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service ruby193-mcollective restart - Restore the HTTP front-end configuration from the backup you created in step one:
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oo-frontend-plugin-modify --restore < filename
