3.2. Environment Requirements
The requirements for Red Hat Enterprise Linux Atomic Host, Red Hat OpenShift Enterprise, Red Hat Enterprise Linux, and Red Hat Gluster Storage is described in this section. A Red Hat Gluster Storage Container Converged with OpenShift environment consists of Red Hat OpenShift Enterprise installed on Red Hat Enterprise Linux Atomic Host or Red Hat Enterprise Linux.
3.2.1. Installing Red Hat Gluster Storage Container Converged with OpenShift on Red Hat Enterprise Linux 7 based OpenShift Enterprise 3.2 Cluster
This section describes the procedures to install Red Hat Gluster Storage Container Converged with OpenShift on Red Hat Enterprise Linux 7 based OpenShift Enterprise 3.2 cluster.
3.2.1.1. Setting up the Openshift Master as the Client
When deploying this solution on Atomic OpenShift it is necessary to deploy a client outside the cluster to install the heketi RPMs. It is optional, though an accepted best practice, to use the OpenShift Master as a client to execute the 'oc' commands across the cluster when installing OpenShift. Generally, this is setup as a non-scheduled node in the cluster. This is the default configuration when using the OpenShift installer. A user can also choose to install their client on their local machine to access the cluster remotely. For more information, see https://access.redhat.com/documentation/en/openshift-enterprise/version-3.2/cli-reference/#installing-the-cli.
Subscribe to the Red Hat Gluster Storage repo
This enables you to install the heketi client packages which are required to setup the client for Red Hat Gluster Storage Container Converged with OpenShift.
# subscription-manager repos --enable=rh-gluster-3-for-rhel-7-server-rpms
# yum install heketi-client heketi-templates
3.2.1.2. Setting up the Red Hat Enterprise Linux 7 Client for Installing Red Hat Gluster Storage Container Converged with OpenShift
To set up the Red Hat Enterprise Linux 7 client for installing Red Hat Gluster Storage Container Converged with OpenShift, perform the following steps:
Subscribe to the Red Hat Gluster Storage repo
This enables you to install the heketi client packages which are required to setup the client for Red Hat Gluster Storage Container Converged with OpenShift.
# subscription-manager repos --enable=rh-gluster-3-for-rhel-7-server-rpms
# yum install heketi-client heketi-templates
Subscribe to the OpenShift Enterprise 3.2 repo
This enables you to install the Openshift client packages
# subscription-manager repos --enable=rhel-7-server-ose-3.2-rpms
# yum install atomic-openshift-clients
# yum install atomic-openshift
3.2.2. Installing Red Hat Gluster Storage Container Converged with OpenShift on Red Hat Enterprise Linux Atomic Host OpenShift Enterprise 3.2 Cluster
Red Hat Enterprise Linux Atomic host does not support the installation of additional RPMs. Hence, an external client is required on Red Hat Enterprise Linux to install the required packages. To set up the client for Red Hat Enterprise Linux Atomic Host based installations, refer Section 3.2.1.2, “Setting up the Red Hat Enterprise Linux 7 Client for Installing Red Hat Gluster Storage Container Converged with OpenShift”
3.2.3. Red Hat OpenShift Enterprise Requirements
The following list provides the Red Hat OpenShift Enterprise requirements:
- The OpenShift cluster must be up and running.
- On each of the OpenShift nodes that will host the Red Hat Gluster Storage container, add the following rules to /etc/sysconfig/iptables in order to open the required ports:
-A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m tcp --dport 24007 -j ACCEPT -A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m tcp --dport 24008 -j ACCEPT -A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m tcp --dport 2222 -j ACCEPT -A OS_FIREWALL_ALLOW -p tcp -m state --state NEW -m multiport --dports 49152:49664 -j ACCEPT
- Execute the following command to reload the iptables:
# systemctl reload iptables
- A cluster-admin user must be created. For more information, see Appendix A, Cluster Administrator Setup
- At least three OpenShift nodes must be created as the storage nodes with at least one raw device each.
- All OpenShift nodes on Red Hat Enterprise Linux systems must have glusterfs-client RPM installed.
- Ensure the nodes have the valid ports opened for communicating with Red Hat Gluster Storage. See the iptables configuration task in Step 1 of Section 4.1, “Preparing the Red Hat OpenShift Enterprise Cluster” for more information.
3.2.4. Red Hat Gluster Storage Requirements
The following list provides the details regarding the Red Hat Gluster Storage requirements:
- Installation of Heketi packages must have valid subscriptions to Red Hat Gluster Storage Server repositories.
- Red Hat Gluster Storage installations must adhere to the requirements outlined in the Red Hat Gluster Storage Installation Guide.
- The versions of Red Hat Enterprise OpenShift and Red Hat Gluster Storage integrated must be compatible, according to the information in Supported Operating Systems section.
- A fully-qualified domain name must be set for Red Hat Gluster Storage server node. Ensure that the correct DNS records exist, and that the fully-qualified domain name is resolvable via both forward and reverse DNS lookup.
3.2.5. Planning Guidelines
The following are the guidelines for setting up Red Hat Gluster Storage Container converged with OpenShift.
- Ensure that the Trusted Storage Pool is not scaled beyond 100 volumes.
- A trusted storage pool consists of a minimum of 3 nodes/peers.
- Distributed-Three-way replication is the only supported volume type.
- Each physical node that needs to host a Red Hat Gluster Storage peer:
- will need a minimum of 32GB RAM.
- is expected to have the same disk type.
- by default the heketidb utilises 32 GB distributed replica volume.
- Red Hat Gluster Storage Container Converged with OpenShift supports upto 14 snapshots per volume.
