8ae3332165
- moved and renamed files/folders based on new structure - updated docs navigation based on new structure - moved CLI to top nav (created commands.jsx and commands-navigation.js) - updated and added redirects - updating to be consistent with standalone categories - changing "overview" link in top nav to lead to where intro was moved (docs/intro) - adding redirects for intro content - deleting old intro folders - format all data/navigation files - deleting old commands folder - reverting changes to glossary page - adjust intro navigation for removal of 'vs' paths - add helm page redirect - fix more redirects - add a missing redirect - fix broken anchor links and formatting mistakes - deleted duplicate section, added redirect, changed link - removed duplicate glossary page
109 lines
4.6 KiB
Plaintext
109 lines
4.6 KiB
Plaintext
---
|
|
layout: docs
|
|
page_title: Configure TLS on an Existing Cluster
|
|
sidebar_title: Configure TLS on an Existing Cluster
|
|
description: Configure TLS on an existing Consul cluster running in Kubernetes
|
|
---
|
|
|
|
# Configuring TLS on an Existing Cluster
|
|
|
|
As of Consul Helm version `0.16.0`, the chart supports TLS for communication
|
|
within the cluster. If you already have a Consul cluster deployed on Kubernetes,
|
|
you may want to configure TLS in a way that minimizes downtime to your applications.
|
|
Consul already supports rolling out TLS on an existing cluster without downtime.
|
|
However, depending on your Kubernetes use case, your upgrade procedure may be different.
|
|
|
|
## Gradual TLS Rollout without Consul Connect
|
|
|
|
If you're **not using Consul Connect**, follow this process.
|
|
|
|
1. Run a Helm upgrade with the following config:
|
|
|
|
```yaml
|
|
global:
|
|
tls:
|
|
enabled: true
|
|
# This configuration sets `verify_outgoing`, `verify_server_hostname`,
|
|
# and `verify_incoming` to `false` on servers and clients,
|
|
# which allows TLS-disabled nodes to join the cluster.
|
|
verify: false
|
|
server:
|
|
updatePartition: <number_of_server_replicas>
|
|
```
|
|
|
|
This upgrade will trigger a rolling update of the clients, as well as any
|
|
other `consul-k8s` components, such as sync catalog or client snapshot deployments.
|
|
|
|
1. Perform a rolling upgrade of the servers, as described in
|
|
[Upgrade Consul Servers](/docs/k8s/operations/upgrading#upgrading-consul-servers).
|
|
|
|
1. Repeat steps 1 and 2, turning on TLS verification by setting `global.tls.verify`
|
|
to `true`.
|
|
|
|
## Gradual TLS Rollout with Consul Connect
|
|
|
|
Because the sidecar Envoy proxies need to talk to the Consul client agent regularly
|
|
for service discovery, we can't enable TLS on the clients without also re-injecting a
|
|
TLS-enabled proxy into the application pods. To perform TLS rollout with minimal
|
|
downtime, we recommend instead to add a new Kubernetes node pool and migrate your
|
|
applications to it.
|
|
|
|
1. Add a new identical node pool.
|
|
|
|
1. Cordon all nodes in the **old** pool by running `kubectl cordon`
|
|
to ensure Kubernetes doesn't schedule any new workloads on those nodes
|
|
and instead schedules onto the new nodes, which shortly will be TLS-enabled.
|
|
|
|
1. Create the following Helm config file for the upgrade:
|
|
|
|
```yaml
|
|
global:
|
|
tls:
|
|
enabled: true
|
|
# This configuration sets `verify_outgoing`, `verify_server_hostname`,
|
|
# and `verify_incoming` to `false` on servers and clients,
|
|
# which allows TLS-disabled nodes to join the cluster.
|
|
verify: false
|
|
server:
|
|
updatePartition: <number_of_server_replicas>
|
|
client:
|
|
updateStrategy: |
|
|
type: OnDelete
|
|
```
|
|
|
|
In this configuration, we're setting `server.updatePartition` to the number of
|
|
server replicas as described in [Upgrade Consul Servers](/docs/k8s/operations/upgrading#upgrading-consul-servers)
|
|
and `client.updateStrategy` to `OnDelete` to manually trigger an upgrade of the clients.
|
|
|
|
1. Run `helm upgrade` with the above config file. The upgrade will trigger an update of all
|
|
components except clients and servers, such as the Consul Connect webhook deployment
|
|
or the sync catalog deployment. Note that the sync catalog and the client
|
|
snapshot deployments will not be in the `ready` state until the clients on their
|
|
nodes are upgraded. It is OK to proceed to the next step without them being ready
|
|
because Kubernetes will keep the old deployment pod around, and so there will be no
|
|
downtime.
|
|
|
|
1. Gradually perform an upgrade of the clients by deleting client pods on the **new** node
|
|
pool.
|
|
|
|
1. At this point, all components (e.g., Consul Connect webhook and sync catalog) should be running
|
|
on the new node pool.
|
|
|
|
1. Redeploy all your Connect-enabled applications.
|
|
One way to trigger a redeploy is to run `kubectl drain` on the nodes in the old pool.
|
|
Now that the Connect webhook is TLS-aware, it will add TLS configuration to
|
|
the sidecar proxy. Also, Kubernetes should schedule these applications on the new node pool.
|
|
|
|
1. Perform a rolling upgrade of the servers described in
|
|
[Upgrade Consul Servers](/docs/k8s/operations/upgrading#upgrading-consul-servers).
|
|
|
|
1. If everything is healthy, delete the old node pool.
|
|
|
|
1. Finally, set `global.tls.verify` to `true` in your Helm config file, remove the
|
|
`client.updateStrategy` property, and perform a rolling upgrade of the servers.
|
|
|
|
-> **Note:** It is possible to do this upgrade without fully duplicating the node pool.
|
|
You could drain a subset of the Kubernetes nodes within your existing node pool and treat it
|
|
as your "new node pool." Then follow the above instructions. Repeat this process for the rest
|
|
of the nodes in the node pool.
|