Installing kuryr-kubernetes manually¶
Configure kuryr-k8s-controller¶
Install kuryr-k8s-controller
in a virtualenv:
$ mkdir kuryr-k8s-controller
$ cd kuryr-k8s-controller
$ virtualenv env
$ git clone https://opendev.org/openstack/kuryr-kubernetes
$ . env/bin/activate
$ pip install -e kuryr-kubernetes
In neutron or in horizon create subnet for pods, subnet for services and a security-group for pods. You may use existing if you like. In case that you decide to create new networks and subnets with the cli, you can follow the services guide, specifically its Default configuration section.
Create /etc/kuryr/kuryr.conf
:
$ cd kuryr-kubernetes
$ ./tools/generate_config_file_samples.sh
$ cp etc/kuryr.conf.sample /etc/kuryr/kuryr.conf
Edit kuryr.conf
:
[DEFAULT]
use_stderr = true
bindir = {path_to_env}/libexec/kuryr
[kubernetes]
api_root = http://{ip_of_kubernetes_apiserver}:8080
ssl_client_crt_file = {path-to-kuryr-k8s-user-cert-file}
ssl_client_key_file = {path-to-kuryr-k8s-user-key-file}
ssl_ca_crt_file = {path-to-k8s-api-ca-cert-file}
[neutron]
auth_url = http://127.0.0.1:35357/v3/
username = admin
user_domain_name = Default
password = ADMIN_PASSWORD
project_name = service
project_domain_name = Default
auth_type = password
[neutron_defaults]
ovs_bridge = br-int
pod_security_groups = {id_of_secuirity_group_for_pods}
pod_subnet = {id_of_subnet_for_pods}
project = {id_of_project}
service_subnet = {id_of_subnet_for_k8s_services}
Note
If you want Kuryr to connect to Kubernetes through an unauthenticated
endpoint make sure to set [kubernetes]ssl_ca_crt_file
and
[kubernetes]token_file
to ""
as they default to the locations where
Kubernetes puts those files for pods. Also don’t set
[kubernetes]ssl_client_crt_file
and [kubernetes]ssl_client_key_file
.
If you use tokens to authenticate use [kubernetes]token_file
to specify
a file having it.
Note
If your Kubernetes cluster has RBAC enabled, make sure the Kuryr user has access to required resources:
rules:
- apiGroups:
- ""
verbs: ["*"]
resources:
- endpoints
- pods
- nodes
- services
- services/status
- namespaces
- apiGroups:
- openstack.org
verbs: ["*"]
resources:
- kuryrnetworks
- kuryrnetworkpolicies
- kuryrloadbalancers
- apiGroups: ["networking.k8s.io"]
resources:
- networkpolicies
verbs:
- get
- list
- watch
- update
- patch
- apiGroups: ["k8s.cni.cncf.io"]
resources:
- network-attachment-definitions
verbs:
- get
You can generate ServiceAccount
definition with correct ClusterRole
using instructions on Generating Kuryr resource definitions for Kubernetes page.
Note that the service_subnet and the pod_subnet should be routable and that the pods should allow service subnet access.
Octavia supports two ways of performing the load balancing between the Kubernetes load balancers and their members:
Layer2: Octavia, apart from the VIP port in the services subnet, creates a Neutron port to the subnet of each of the members. This way the traffic from the Service Haproxy to the members will not go through the router again, only will have gone through the router to reach the service.
Layer3: Octavia only creates the VIP port. The traffic from the service VIP to the members will go back to the router to reach the pod subnet. It is important to note that it will have some performance impact depending on the SDN.
To support the L3 mode (both for Octavia and for the deprecated Neutron-LBaaSv2):
There should be a router between the two subnets.
The pod_security_groups setting should include a security group with a rule granting access to all the CIDR of the service subnet, e.g.:
$ openstack security group create --project k8s_cluster_project \ service_pod_access_sg $ openstack security group rule create --project k8s_cluster_project \ --remote-ip cidr_of_service_subnet --ethertype IPv4 --protocol tcp \ service_pod_access_sg
The uuid of this security group id should be added to the comma separated list of pod security groups. pod_security_groups in [neutron_defaults].
Alternatively, to support Octavia L2 mode:
The pod security_groups setting should include a security group with a rule granting access to all the CIDR of the pod subnet, e.g.:
$ openstack security group create --project k8s_cluster_project \ octavia_pod_access_sg $ openstack security group rule create --project k8s_cluster_project \ --remote-ip cidr_of_pod_subnet --ethertype IPv4 --protocol tcp \ octavia_pod_access_sg
The uuid of this security group id should be added to the comma separated list of pod security groups. pod_security_groups in [neutron_defaults].
Run kuryr-k8s-controller:
$ kuryr-k8s-controller --config-file /etc/kuryr/kuryr.conf -d
Alternatively you may run it in screen:
$ screen -dm kuryr-k8s-controller --config-file /etc/kuryr/kuryr.conf -d
Configure kuryr-cni¶
On every kubernetes minion node (and on master if you intend to run containers there) you need to configure kuryr-cni.
Install kuryr-cni
in a virtualenv:
$ mkdir kuryr-k8s-cni
$ cd kuryr-k8s-cni
$ virtualenv env
$ . env/bin/activate
$ git clone https://opendev.org/openstack/kuryr-kubernetes
$ pip install -e kuryr-kubernetes
Create /etc/kuryr/kuryr.conf
:
$ cd kuryr-kubernetes
$ ./tools/generate_config_file_samples.sh
$ cp etc/kuryr.conf.sample /etc/kuryr/kuryr.conf
Edit kuryr.conf
:
[DEFAULT]
use_stderr = true
bindir = {path_to_env}/libexec/kuryr
[kubernetes]
api_root = http://{ip_of_kubernetes_apiserver}:8080
Link the CNI binary to CNI directory, where kubelet would find it:
$ mkdir -p /opt/cni/bin
$ ln -s $(which kuryr-cni) /opt/cni/bin/
Create the CNI config file for kuryr-cni: /etc/cni/net.d/10-kuryr.conflist
.
Kubelet would only use the lexicographically first file in that directory, so
make sure that it is kuryr’s config file:
{
"name": "kuryr",
"cniVersion": "0.3.1",
"plugins": [
{
"type": "kuryr-cni",
"kuryr_conf": "/etc/kuryr/kuryr.conf",
"debug": true
}
]
}
Install os-vif
and oslo.privsep
libraries globally. These modules
are used to plug interfaces and would be run with raised privileges. os-vif
uses sudo
to raise privileges, and they would need to be installed globally
to work correctly:
$ deactivate
$ sudo pip install 'oslo.privsep>=1.20.0' 'os-vif>=1.5.0'
Configure Kuryr CNI Daemon¶
Kuryr CNI Daemon is a service designed to increased scalability of the Kuryr operations done on Kubernetes nodes. More information can be found on CNI Daemon page.
Kuryr CNI Daemon, should be installed on every Kubernetes node, so following steps need to be repeated.
Note
You can tweak configuration of some timeouts to match your environment. It’s crucial for scalability of the whole deployment. In general the timeout to serve CNI request from kubelet to Kuryr is 180 seconds. After that time kubelet will retry the request. Additionally there are two configuration options:
[cni_daemon]
vif_annotation_timeout=60
pyroute2_timeout=10
vif_annotation_timeout
is time the Kuryr CNI Daemon will wait for Kuryr
Controller to create a port in Neutron and add information about it to Pod’s
metadata. If either Neutron or Kuryr Controller doesn’t keep up with high
number of requests, it’s advised to increase this timeout. Please note that
increasing it over 180 seconds will not have any effect as the request will
time out anyway and will be retried (which is safe).
pyroute2_timeout
is internal timeout of pyroute2 library, that is
responsible for doing modifications to Linux Kernel networking stack (e.g.
moving interfaces to Pod’s namespaces, adding routes and ports or assigning
addresses to interfaces). When serving a lot of ADD/DEL CNI requests on a
regular basis it’s advised to increase that timeout. Please note that the
value denotes maximum time to wait for kernel to complete the operations.
If operation succeeds earlier, request isn’t delayed.
Run kuryr-daemon:
$ kuryr-daemon --config-file /etc/kuryr/kuryr.conf -d
Alternatively you may run it in screen:
$ screen -dm kuryr-daemon --config-file /etc/kuryr/kuryr.conf -d
Kuryr CNI Daemon health checks¶
The CNI daemon health checks allow the deployer or the orchestration layer (like for example Kubernetes or OpenShift) to probe the CNI daemon for liveness and readiness.
If you want to make use of all of its facilities, you should run the kuryr-daemon in its own cgroup. It will get its own cgroup if you:
Run it as a systemd service,
run it containerized,
create a memory cgroup for it.
In order to make the daemon run in its own cgroup, you can do the following:
systemd-run --unit=kuryr-daemon --scope --slice=kuryr-cni \
kuryr-daemon --config-file /etc/kuryr/kuryr.conf -d
After this, with the CNI daemon running inside its own cgroup, we can enable the CNI daemon memory health check. This health check allows us to limit the memory consumption of the CNI Daemon. The health checks will fail if CNI starts taking more memory that it is set and the orchestration layer should restart. The setting is:
[cni_health_server]
max_memory_usage = 4096 # Set the memory limit to 4GiB