This document discusses the requirements, current expected behavior, and how to try out what exists so far. In addition, it covers the installation with the default CNI (OpenShiftSDN), as well as with the Kuryr SDN.
- OpenStack Platform Support
- Known Issues and Workarounds
- Using the OSP 4 installer with Kuryr
- Troubleshooting your cluster
- Customizing your install
- Learn about the OpenShift on OpenStack networking infrastructure design
In order to run the latest version of the installer in OpenStack, at a bare minimum you need the following quota to run a default cluster. While it is possible to run the cluster with fewer resources than this, it is not recommended. Certain cases, such as deploying without FIPs, or deploying with an external load balancer are documented below, and are not included in the scope of this recommendation. If you are planning on using Kuryr, or want to learn more about it, please read through the Kuryr documentation. NOTE: The installer has been tested and developed on Red Hat OSP 13.
For a successful installation it is required:
- Floating IPs: 2
- Security Groups: 3
- Security Group Rules: 60
- Routers: 1
- Subnets: 1
- RAM: 112 GB
- vCPUs: 28
- Volume Storage: 175 GB
- Instances: 7
- Depending on the type of image registry backend either 1 Swift container or an additional 100 GB volume.
You may need to increase the security group related quotas from their default values. For example (as an OpenStack administrator):
openstack quota set --secgroups 8 --secgroup-rules 100 <project>`The default deployment stands up 3 master nodes, which is the minimum amount required for a cluster. For each master node you stand up, you will need 1 instance, and 1 port available in your quota. They should be assigned a flavor with at least 16 GB RAM, 4 vCPUs, and 25 GB Disk. It is theoretically possible to run with a smaller flavor, but be aware that if it takes too long to stand up services, or certain essential services crash, the installer could time out, leading to a failed install.
The default deployment stands up 3 worker nodes. In our testing we determined that 2 was the minimum number of workers you could have to get a successful install, but we don't recommend running with that few. Worker nodes host the applications you run on OpenShift, so it is in your best interest to have more of them. See here for more information. The flavor assigned to the worker nodes should have at least 2 vCPUs, 8 GB RAM and 25 GB Disk. However, if you are experiencing Out Of Memory issues, or your installs are timing out, you should increase the size of your flavor to match the masters: 4 vCPUs and 16 GB RAM.
The bootstrap node is a temporary node that is responsible for standing up the control plane on the masters. Only one bootstrap node will be stood up and it will be deprovisioned once the production control plane is ready. To do so, you need 1 instance, and 1 port. We recommend a flavor with a minimum of 16 GB RAM, 4 vCPUs, and 25 GB Disk.
If Swift is available in the cloud where the installation is being performed, it is used as the default backend for the OpenShift image registry. At the time of installation only an empty container is created without loading any data. Later on, for the system to work properly, you need to have enough free space to store the container images.
In this case the user must have swiftoperator permissions. As an OpenStack administrator:
openstack role add --user <user> --project <project> swiftoperatorIf Swift is not available, the PVC storage is used as the backend. For this purpose, a persistent volume of 100 GB will be created in Cinder and mounted to the image registry pod during the installation.
Note: Since Cinder supports only ReadWriteOnce access mode, it's not possible to have more than one replica of the image registry pod.
Etcd, which runs on the control plane nodes, has disk requirements that need to be met to ensure the stability of the cluster.
Generally speaking, it is advised to choose for the control plane nodes a flavour that is backed by SSD in order to reduce latency.
If the ephemeral disk that gets attached to instances of the chosen flavor does not meet etcd requirements, check if the cloud has a more performant volume type and use a custom install-config.yaml to deploy the control plane with root volumes. However, please note that Ceph RBD (and any other network-attached storage) can result in unpredictable network latencies. Prefer PCI passthrough of an NVM device instead.
In order to measure the performance of your disk, you can use fio:
sudo podman run \
--volume "/var/lib/etcd:/mount:z" \
docker.io/ljishen/fio \
--directory=/mount \
--name=iotest \
--size=22m \
--bs=2300 \
--fdatasync=1 \
--ioengine=sync \
--rw=writeLook for the 99th percentile under fsync/fdatasync/sync_file_range -> sync percentiles.
Caution about the measurement units: fio fluidly adjusts the scale between ms/µs/ns depending on the numbers.
Look for spikes. Even if the baseline latency looks good, there may be spikes where it comes up, triggering issues that result in API being unavailable.
Prometheus collects etcd-specific metrics.
Once the cluster is up, Prometheus provides useful metrics here:
https://prometheus-k8s-openshift-monitoring.apps.<cluster name>.<domain name>/graph?g0.range_input=2h&g0.stacked=0&g0.expr=histogram_quantile(0.99%2C%20rate(etcd_disk_wal_fsync_duration_seconds_bucket%5B5m%5D))&g0.tab=0&g1.range_input=2h&g1.expr=histogram_quantile(0.99%2C%20rate(etcd_disk_backend_commit_duration_seconds_bucket%5B5m%5D))&g1.tab=0&g2.range_input=2h&g2.expr=etcd_server_health_failures&g2.tab=0
Click "Login with OpenShift", enter kubeadmin and the password printed out by the installer.
The units are in seconds and should stay under 10ms (0.01s) at all times. The etcd_health graph should remain at 0.
In order to collect relevant information interactively, run the conformance tests:
git clone https://github.com/openshift/origin/
make WHAT=cmd/openshift-tests
export KUBECONFIG=<path/to/kubeconfig>
_output/local/bin/linux/amd64/openshift-tests run openshift/conformance/parallel
The entire test suite takes over an hour to complete. Run it and check the Prometheus logs afterwards.
The public network should be created by the OpenStack administrator. Verify the name/ID of the 'External' network:
openstack network list --long -c ID -c Name -c "Router Type"
+--------------------------------------+----------------+-------------+
| ID | Name | Router Type |
+--------------------------------------+----------------+-------------+
| 148a8023-62a7-4672-b018-003462f8d7dc | public_network | External |
+--------------------------------------+----------------+-------------+NOTE: If the neutron trunk service plug-in is enabled, trunk port will be created by default. For more information, please refer to neutron trunk port.
Nova metadata service must be enabled and available at http://169.254.169.254. Currently the service is used to deliver Ignition config files to Nova instances and provide information about the machine to kubelet.
The creation of images in Glance should be available to the user. Now Glance is used for two things:
-
Right after the installation starts, the installer automatically uploads the actual
RHCOSbinary image to Glance with the name<clusterID>-rhcos. The image exists throughout the life of the cluster and is removed along with it. -
The installer stores bootstrap ignition configs in a temporary image called
<clusterID>-ignition. This is not a canonical use of the service, but this solution allows us to unify the installation process, since Glance is available on all OpenStack clouds, unlike Swift. The image exists for a limited period of time while the bootstrap process is running (normally 10-30 minutes), and then is automatically deleted.
You must have a clouds.yaml file in order to run the installer. The installer will look for a clouds.yaml file in the following locations in order:
- Value of
OS_CLIENT_CONFIG_FILEenvironment variable - Current directory
- unix-specific user config directory (
~/.config/openstack/clouds.yaml) - unix-specific site config directory (
/etc/openstack/clouds.yaml)
In many OpenStack distributions, you can generate a clouds.yaml file through Horizon. Otherwise, you can make a clouds.yaml file yourself.
Information on this file can be found here and it looks like:
clouds:
shiftstack:
auth:
auth_url: http://10.10.14.42:5000/v3
project_name: shiftstack
username: shiftstack_user
password: XXX
user_domain_name: Default
project_domain_name: Default
dev-evn:
region_name: RegionOne
auth:
username: 'devuser'
password: XXX
project_name: 'devonly'
auth_url: 'https://10.10.14.22:5001/v2.0'The file can contain information about several clouds. For instance, the example above describes two clouds: shiftstack and dev-evn.
In order to determine which cloud to use, the user can either specify it in the install-config.yaml file under platform.openstack.cloud or with OS_CLOUD environment variable. If both are omitted, then the cloud name defaults to openstack.
If your OpenStack cluster uses self signed CA certificates for endpoint authentication, you will need a few additional steps to run the installer. First, make sure that the host running the installer trusts your CA certificates. If you want more information on how to do this, refer to the Red Hat OpenStack Plaform documentation. In the future, we plan to modify the installer to be able to trust certificates independently of the host OS.
sudo cp ca.crt.pem /etc/pki/ca-trust/source/anchors/
sudo update-ca-trust extractNext, you should add the cacert key to your clouds.yaml. Its value should be a valid path to your CA cert that does not require root privilege to read.
clouds:
shiftstack:
auth: ...
cacert: "ca.crt.pem"If you would like to set up an isolated development environment, you may use a bare metal host running CentOS 7. The following repository includes some instructions and scripts to help with creating a single-node OpenStack development environment for running the installer. Please refer to this documentation for further details.
OpenStack support has known issues. We will be documenting workarounds until we are able to resolve these bugs in the upcoming releases. To see the latest status of any bug, read through bugzilla or github link provided in that bug's description. If you know of a possible workaround that hasn't been documented yet, please comment in that bug's tracking link so we can address it as soon as possible. Also note that any bug listed in these documents is already a top priority issue for the dev team, and will be resolved as soon as possible. If you find more bugs during your runs, please read the section on issue reporting.
Please head to try.openshift.com to get the latest versions of the installer, and instructions to run it.
Before running the installer, we recommend you create a directory for each cluster you plan to deploy. See the documents on the recommended workflow for more information about why you should do it this way.
mkdir ostest
cp install-config.yaml ostest/install-config.yamlAll the OpenShift nodes get created in an OpenStack tenant network and as such, can't be accessed directly in most OpenStack deployments. We will briefly explain how to set up access to the OpenShift API with and without floating IP addresses.
This method allows you to attach two floating IP (FIP) addresses to endpoints in OpenShift.
A standard deployment uses three floating IP addresses in total:
- External access to the OpenShift API
- External access to the workloads (apps) running on the OpenShift cluster
- Temporary IP address for bootstrap log collection
The first two addresses (API and Ingress) are generally created up-front and have the corresponding DNS records resolve to them.
The third floating IP is created automatically by the installer and will be destroyed along with all the other bootstrap resources. If the bootstrapping process fails, the installer will try to SSH into the bootstrap node and collect the logs.
The deployed OpenShift cluster will need two floating IP addresses, one to attach to the API load balancer (lb FIP), and one for the OpenShift applications (apps FIP). Note that the LB FIP is the IP address you will add to your install-config.yaml or select in the interactive installer prompt.
You can create them like so:
openstack floating ip create --description "API <cluster name>.<base domain>" <external network>
# => <lb FIP>
openstack floating ip create --description "Ingress <cluster name>.<base domain>" <external network>
# => <apps FIP>NOTE: These IP addresses will not show up attached to any particular server (e.g. when running openstack server list). Similarly, the API and Ingress ports will always be in the DOWN state.
This is because the ports are not attached to the servers directly. Instead, their fixed IP addresses are managed by keepalived. This has no record in Neutron's database and as such, is not visible to OpenStack.
The network traffic will flow through even though the IPs and ports do not show up in the servers.
For more details, read the OpenShift on OpenStack networking infrastructure design document.
You will also need to add the following records to your DNS:
api.<cluster name>.<base domain>. IN A <lb FIP>
*.apps.<cluster name>.<base domain>. IN A <apps FIP>
If you're unable to create and publish these DNS records, you can add them to your /etc/hosts file.
<lb FIP> api.<cluster name>.<base domain>
<apps FIP> console-openshift-console.apps.<cluster name>.<base domain>
<apps FIP> integrated-oauth-server-openshift-authentication.apps.<cluster name>.<base domain>
<apps FIP> oauth-openshift.apps.<cluster name>.<base domain>
<apps FIP> prometheus-k8s-openshift-monitoring.apps.<cluster name>.<base domain>
<apps FIP> grafana-openshift-monitoring.apps.<cluster name>.<base domain>
<apps FIP> <app name>.apps.<cluster name>.<base domain>
WARNING: this workaround will make the API accessible only to the computer with these /etc/hosts entries. This is fine for your own testing (and it is enough for the installation to succeed), but it is not enough for a production deployment. In addition, if you create new OpenShift apps or routes, you will have to add their entries too, because /etc/hosts does not support wildcard entries.
If you have specified the API floating IP (either via the installer prompt or by adding the lbFloatingIP entry in your install-config.yaml) the installer will attach the Floating IP address to the api-port automatically.
If you have created the API DNS record, you should be able access the OpenShift API.
The installer doesn't currently handle the Ingress floating IP address the same way it does the API one.
To make the OpenShift Ingress access available (this includes logging into the deployed cluster), you will need to attach the Ingress floating IP to the ingress-port after the cluster is created.
That can be done in the following steps:
openstack port show <cluster name>-<clusterID>-ingress-portThen attach the FIP to it:
openstack floating ip set --port <cluster name>-<clusterID>-ingress-port <apps FIP>This assumes the floating IP and corresponding *.apps DNS record exists.
If you cannot or don't want to pre-create a floating IP address, the installation should still succeed, however the installer will fail waiting for the API.
WARNING: The installer will fail if it can't reach the bootstrap OpenShift API in 30 minutes.
Even if the installer times out, the OpenShift cluster should still come up. Once the bootstrapping process is in place, it should all run to completion. So you should be able to deploy OpenShift without any floating IP addresses and DNS records and create everything yourself after the cluster is up.
To run the installer, you have the option of using the interactive wizard, or providing your own install-config.yaml file for it. The wizard is the easier way to run the installer, but passing your own install-config.yaml enables you to use more fine grained customizations. If you are going to create your own install-config.yaml, read through the available OpenStack customizations. For information on running the installer with Kuryr, see the Kuryr docs.
./openshift-install create cluster --dir ostestIf you want to create an install config without deploying a cluster, you can use the command:
./openshift-install create install-config --dir ostestCurrently:
- Deploys an isolated tenant network
- Deploys a bootstrap instance to bootstrap the OpenShift cluster
- Deploys 3 master nodes
- Once the masters are deployed, the bootstrap instance is destroyed
- Deploys 3 worker nodes
Look for a message like this to verify that your install succeeded:
INFO Install complete!
INFO To access the cluster as the system:admin user when using 'oc', run 'export KUBECONFIG=/home/stack/ostest/auth/kubeconfig'
INFO Access the OpenShift web-console here: https://console-openshift-console.apps.ostest.shiftstack.com
INFO Login to the console with user: kubeadmin, password: xxxIf you want to see the status of the apps and services in your cluster during, or after a deployment, first export your administrator's kubeconfig:
export KUBECONFIG=ostest/auth/kubeconfigAfter a finished deployment, there should be a node for each master and worker server created. You can check this with the command:
oc get nodesTo see the version of your OpenShift cluster, do:
oc get clusterversionTo see the status of you operators, do:
oc get clusteroperatorFinally, to see all the running pods in your cluster, you can do:
oc get pods -ATo destroy the cluster, point it to your cluster with this command:
./openshift-install --log-level debug destroy cluster --dir ostestThen, you can delete the folder containing the cluster metadata:
rm -rf ostest/This documents how to shift from the internal load balancer, which is intended for internal networking needs, to an external load balancer.
The load balancer must serve ports 6443, 443, and 80 to any users of the system. Port 22623 is for serving ignition start-up configurations to the OpenShift nodes and should not be reachable outside of the cluster.
The first step is to add floating IPs to all the master nodes:
openstack floating ip create --port master-port-0 <public network>
openstack floating ip create --port master-port-1 <public network>
openstack floating ip create --port master-port-2 <public network>Once complete you can see your floating IPs using:
openstack server listThese floating IPs can then be used by the load balancer to access the cluster. An example of HAProxy configuration for port 6443 is below.
listen <cluster name>-api-6443
bind 0.0.0.0:6443
mode tcp
balance roundrobin
server <cluster name>-master-2 <floating ip>:6443 check
server <cluster name>-master-0 <floating ip>:6443 check
server <cluster name>-master-1 <floating ip>:6443 checkThe other port configurations are identical.
The next step is to allow network access from the load balancer network to the master nodes:
openstack security group rule create master --remote-ip <load balancer CIDR> --ingress --protocol tcp --dst-port 6443
openstack security group rule create master --remote-ip <load balancer CIDR> --ingress --protocol tcp --dst-port 443
openstack security group rule create master --remote-ip <load balancer CIDR> --ingress --protocol tcp --dst-port 80You could also specify a specific IP address with /32 if you wish.
You can verify the operation of the load balancer now if you wish, using the curl commands given below.
Now the DNS entry for api.<cluster name>.<base domain> needs to be updated to point to the new load balancer:
<load balancer ip> api.<cluster-name>.<base domain>
The external load balancer should now be operational along with your own DNS solution. The following curl command is an example of how to check functionality:
curl https://<loadbalancer-ip>:6443/version --insecureResult:
{
"major": "1",
"minor": "11+",
"gitVersion": "v1.11.0+ad103ed",
"gitCommit": "ad103ed",
"gitTreeState": "clean",
"buildDate": "2019-01-09T06:44:10Z",
"goVersion": "go1.10.3",
"compiler": "gc",
"platform": "linux/amd64"
}Another useful thing to check is that the ignition configurations are only available from within the deployment. The following command should only succeed from a node in the OpenShift cluster:
curl https://<loadbalancer ip>:22623/config/master --insecurePlease see the Issue Tracker for current known issues. Please report a new issue if you do not find an issue related to any trouble you’re having.