Talos Kubernetes cluster operations#

This chapter describes the operations that can be performed on the Talos Kubernetes cluster powering the Nokia EDA platform.

Making cluster configuration changes#

The Talos Kubernetes cluster configuration is defined declaratively in a set of Talos machine configuration files. The EDA installation tool, edaadm, uses a single EDAADM configuration file to define the cluster configuration. This file provides a higher-level abstraction of the cluster configuration, and edaadm generate command translates it into the Talos-specific manifests.

In order to make configuration changes to the live cluster, follow this procedure:

1. Edit the EDAADM configuration file to reflect the changes you want to make.
2. Run the edaadm generate command to generate the set of Talos-specific manifests.

3. Apply the changes to each node of the EDA cluster using the following command:

   # apply to all nodes in the EDA cluster
   edaadm apply-config --reprovision -c <path to the EDAADM configuration file> \
   -n <name of the node>
   

To illustrate the complete workflow, let's work through an example of changing the nameservers for all Kubernetes nodes in the EDA cluster.

For this example, the EDAADM configuration file defines "10.171.0.1","10.171.0.2","10.171.0.3" as the nameservers. Verify the configured nameservers with the talosctl command:

talosctl --talosconfig talosconfig.yaml get resolvers -n 192.168.123.101 -e 192.168.123.101

NODE              NAMESPACE   TYPE             ID          VERSION   RESOLVERS                                  SEARCH DOMAINS
192.168.123.101   network     ResolverStatus   resolvers   3         ["10.171.0.1","10.171.0.2","10.171.0.3"]   []

Change the .k8s.nameservers.servers list in the EDAADM configuration file to your desired set of nameservers, e.g. ["10.171.0.1","8.8.8.8","1.1.1.1"]:

git diff eda-6-node.yaml

diff --git a/blueprints/eda-6-node.yaml b/blueprints/eda-6-node.yaml
index 386c861..1730cec 100644
--- a/blueprints/eda-6-node.yaml
+++ b/blueprints/eda-6-node.yaml
@@ -32,8 +32,8 @@ k8s:
   nameservers:
     servers:
       - 10.171.0.1
-      - 10.171.0.2
-      - 10.171.0.3
+      - 8.8.8.8
+      - 1.1.1.1
   primaryNode: vm-cp-01
   stack: dual
   time:

After the edits are made, run the edaadm generate command to generate the set of Talos-specific manifests:

edaadm generate -c eda-6-node.yaml

This will regenerate the set of Talos-specific manifests with the new nameservers.

Next, apply the changes to each node of the EDA cluster using the edaadm apply-config --reprovision command:

edaadm apply-config --reprovision -c eda-6-node.yaml -n vm-cp-01 #(1)!

Applied configuration without a reboot

1. This command applies the changes to a single node of the EDA cluster. Repeat the command for each node of the EDA cluster.

Talos allows nameserver changes to be applied immediately, so the command immediately applies the changes to the node:

The change of nameservers is allowed to be applied immediately, so the command will apply the changes without a reboot:

talosctl --talosconfig talosconfig.yaml get resolvers -n 192.168.123.101 -e 192.168.123.101
NODE              NAMESPACE   TYPE             ID          VERSION   RESOLVERS                            SEARCH DOMAINS
192.168.123.101   network     ResolverStatus   resolvers   4         ["10.171.0.1","8.8.8.8","1.1.1.1"]   []