67 lines
2.0 KiB
Markdown
67 lines
2.0 KiB
Markdown
# Provisioning Pod Network Routes
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Pods scheduled to a node receive an IP address from the node's Pod CIDR range. At this point pods can not communicate with other pods running on different nodes due to missing network [routes](https://cloud.google.com/compute/docs/vpc/routes).
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In this lab you will create a route for each worker node that maps the node's Pod CIDR range to the node's internal IP address.
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> There are [other ways](https://kubernetes.io/docs/concepts/cluster-administration/networking/#how-to-achieve-this) to implement the Kubernetes networking model.
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## The Routing Table
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**On each worker node**, add the following routes:
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```bash
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ip route add 10.200.0.0/24 via 192.168.8.20
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ip route add 10.200.1.0/24 via 192.168.8.21
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ip route add 10.200.2.0/24 via 192.168.8.22
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```
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> Don't take care of the `RTNETLINK answers: File exists` message, it appears just when you try to add an existing route, not a real problem.
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List the routes in the `kubernetes-the-hard-way` VPC network:
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```bash
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ip route
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```
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> Output (example for worker-0):
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```bash
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default via 192.168.8.1 dev ens18 proto static
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10.200.0.0/24 via 192.168.8.20 dev ens18
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10.200.1.0/24 via 192.168.8.21 dev ens18
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10.200.2.0/24 via 192.168.8.22 dev ens18
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192.168.8.0/24 dev ens18 proto kernel scope link src 192.168.8.21
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```
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To make it persistent (if reboot), you need to edit your network configuration (depends on your Linux distribution).
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Example for **Ubuntu 18.04** and higher:
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```bash
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vi /etc/netplan/00-installer-config.yaml
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```
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> Content (example for worker-0, **don't specify the POD CIDR associated with the current node**):
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```bash
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# This is the network config written by 'subiquity'
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network:
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ethernets:
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ens18:
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addresses:
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- 192.168.8.10/24
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gateway4: 192.168.8.1
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nameservers:
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addresses:
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- 9.9.9.9
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routes:
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- to: 10.200.1.0/24
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via: 192.168.8.21
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- to: 10.200.2.0/24
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via: 192.168.8.22
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version: 2
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```
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Next: [Deploying the DNS Cluster Add-on](12-dns-addon.md)
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