mirror of
https://github.com/rancher/rancher-docs.git
synced 2026-05-15 09:33:30 +00:00
Overlay test updated
Standardized names and etc. Used `operator: Exists` toleration from the rancher overlay test rather than the no schedule and execute from the RKE. Added some verbosity
This commit is contained in:
Tejeev
GitHub
@@ -14,9 +14,9 @@ Double check if all the [required ports]({{<baseurl>}}/rancher/v2.x/en/cluster-p
|
||||
|
||||
The pod can be scheduled to any of the hosts you used for your cluster, but that means that the NGINX ingress controller needs to be able to route the request from `NODE_1` to `NODE_2`. This happens over the overlay network. If the overlay network is not functioning, you will experience intermittent TCP/HTTP connection failures due to the NGINX ingress controller not being able to route to the pod.
|
||||
|
||||
To test the overlay network, you can launch the following `DaemonSet` definition. This will run a `swiss-army-knife` container on every host (image was developed by Rancher engineers), which we will use to run a `ping` test between containers on all hosts.
|
||||
To test the overlay network, you can launch the following `DaemonSet` definition. This will run a `swiss-army-knife` container on every host (image was developed by Rancher engineers and can be found here: https://github.com/leodotcloud/swiss-army-knife), which we will use to run a `ping` test between containers on all hosts.
|
||||
|
||||
1. Save the following file as `ds-overlaytest.yml`
|
||||
1. Save the following file as `overlaytest.yml`
|
||||
|
||||
```
|
||||
apiVersion: apps/v1
|
||||
@@ -30,126 +30,62 @@ To test the overlay network, you can launch the following `DaemonSet` definition
|
||||
template:
|
||||
metadata:
|
||||
labels:
|
||||
name: ds-overlaytest
|
||||
name: overlaytest
|
||||
spec:
|
||||
tolerations:
|
||||
- effect: NoExecute
|
||||
key: "node-role.kubernetes.io/etcd"
|
||||
value: "true"
|
||||
- effect: NoSchedule
|
||||
key: "node-role.kubernetes.io/controlplane"
|
||||
value: "true"
|
||||
- operator: Exists
|
||||
containers:
|
||||
- image: leodotcloud/swiss-army-knife
|
||||
imagePullPolicy: Always
|
||||
name: overlaytest
|
||||
command: ["sh", "-c", "tail -f /dev/null"]
|
||||
terminationMessagePath: /dev/termination-log
|
||||
|
||||
```
|
||||
|
||||
2. Launch it using `kubectl create -f ds-overlaytest.yml`
|
||||
2. Launch it using `kubectl create -f overlaytest.yml`
|
||||
3. Wait until `kubectl rollout status ds/overlaytest -w` returns: `daemon set "overlaytest" successfully rolled out`.
|
||||
4. Run the following command, from the same location, to let each container on every host ping each other (it's a single line bash command).
|
||||
|
||||
4. Run the following script, from the same location. It will have each `overlaytest` container on every host ping each other:
|
||||
```
|
||||
### Check if overlay network is functioning correctly
|
||||
|
||||
The pod can be scheduled to any of the hosts you used for your cluster, but that means that the NGINX ingress controller needs to be able to route the request from `NODE_1` to `NODE_2`. This happens over the overlay network. If the overlay network is not functioning, you will experience intermittent TCP/HTTP connection failures due to the NGINX ingress controller not being able to route to the pod.
|
||||
|
||||
To test the overlay network, you can launch the following `DaemonSet` definition. This will run a `swiss-army-knife` container on every host (image was developed by Rancher engineers), which we will use to run a `ping` test between containers on all hosts.
|
||||
|
||||
1. Save the following file as `ds-overlaytest.yml`
|
||||
|
||||
```
|
||||
apiVersion: apps/v1
|
||||
kind: DaemonSet
|
||||
metadata:
|
||||
name: overlaytest
|
||||
spec:
|
||||
selector:
|
||||
matchLabels:
|
||||
name: overlaytest
|
||||
template:
|
||||
metadata:
|
||||
labels:
|
||||
name: ds-overlaytest
|
||||
spec:
|
||||
tolerations:
|
||||
- effect: NoExecute
|
||||
key: "node-role.kubernetes.io/etcd"
|
||||
value: "true"
|
||||
- effect: NoSchedule
|
||||
key: "node-role.kubernetes.io/controlplane"
|
||||
value: "true"
|
||||
containers:
|
||||
- image: leodotcloud/swiss-army-knife
|
||||
imagePullPolicy: Always
|
||||
name: overlaytest
|
||||
command: ["sh", "-c", "tail -f /dev/null"]
|
||||
terminationMessagePath: /dev/termination-log
|
||||
#!/bin/bash
|
||||
echo "=> Start network overlay test"
|
||||
kubectl get pods -l name=overlaytest -o jsonpath='{range .items[*]}{@.metadata.name}{" "}{@.spec.nodeName}{"\n"}{end}' |
|
||||
while read spod shost
|
||||
do kubectl get pods -l name=overlaytest -o jsonpath='{range .items[*]}{@.status.podIP}{" "}{@.spec.nodeName}{"\n"}{end}' |
|
||||
while read tip thost
|
||||
do kubectl --request-timeout='10s' exec $spod -c overlaytest -- /bin/sh -c "ping -c2 $tip > /dev/null 2>&1"
|
||||
RC=$?
|
||||
if [ $RC -ne 0 ]
|
||||
then echo FAIL: $spod on $shost cannot reach pod IP $tip on $thost
|
||||
else echo $shost can reach $thost
|
||||
fi
|
||||
done
|
||||
done
|
||||
echo "=> End network overlay test"
|
||||
```
|
||||
|
||||
2. Launch it using `kubectl create -f ds-overlaytest.yml`
|
||||
3. Wait until `kubectl rollout status ds/overlaytest -w` returns: `daemon set "overlaytest" successfully rolled out`.
|
||||
4. Run the following command, from the same location, to let each container on every host ping each other (it's a single line bash command).
|
||||
|
||||
```
|
||||
echo "=> Start network overlay test"; kubectl get pods -l name=ds-overlaytest -o jsonpath='{range .items[*]}{@.metadata.name}{" "}{@.spec.nodeName}{"\n"}{end}' | while read spod shost; do kubectl get pods -l name=ds-overlaytest -o jsonpath='{range .items[*]}{@.status.podIP}{" "}{@.spec.nodeName}{"\n"}{end}' | while read tip thost; do kubectl --request-timeout='10s' exec $spod -- /bin/sh -c "ping -c2 $tip > /dev/null 2>&1"; RC=$?; if [ $RC -ne 0 ]; then echo $shost cannot reach $thost; fi; done; done; echo "=> End network overlay test"
|
||||
```
|
||||
|
||||
5. When this command has finished running, the output indicating everything is correct is:
|
||||
5. When this command has finished running, it will output the state of each route:
|
||||
|
||||
```
|
||||
=> Start network overlay test
|
||||
Pinging from pod overlaytest-4cpx5 on host NODE1
|
||||
to pod ip 10.42.1.29 on host NODE1
|
||||
to pod ip 10.42.2.19 on host NODE2
|
||||
to pod ip 10.42.4.12 on host NODE3
|
||||
Pinging from pod overlaytest-vms6w on host NODE2
|
||||
to pod ip 10.42.1.29 on host NODE1
|
||||
to pod ip 10.42.2.19 on host NODE2
|
||||
to pod ip 10.42.4.12 on host NODE3
|
||||
Error from server (NotFound): pods "wk2" not found
|
||||
FAIL: overlaytest-5bglp on wk2 cannot reach pod IP 10.42.7.3 on wk2
|
||||
Error from server (NotFound): pods "wk2" not found
|
||||
FAIL: overlaytest-5bglp on wk2 cannot reach pod IP 10.42.0.5 on cp1
|
||||
Error from server (NotFound): pods "wk2" not found
|
||||
FAIL: overlaytest-5bglp on wk2 cannot reach pod IP 10.42.2.12 on wk1
|
||||
command terminated with exit code 1
|
||||
FAIL: overlaytest-v4qkl on cp1 cannot reach pod IP 10.42.7.3 on wk2
|
||||
cp1 can reach cp1
|
||||
cp1 can reach wk1
|
||||
command terminated with exit code 1
|
||||
FAIL: overlaytest-xpxwp on wk1 cannot reach pod IP 10.42.7.3 on wk2
|
||||
wk1 can reach cp1
|
||||
wk1 can reach wk1
|
||||
=> End network overlay test
|
||||
```
|
||||
|
||||
If you see error in the output, that means that the [required ports]({{<baseurl>}}/rancher/v2.x/en/cluster-provisioning/node-requirements/#networking-requirements/) for overlay networking are not opened between the hosts indicated.
|
||||
|
||||
If a path fails the overlay test, you will see errors like the following:
|
||||
|
||||
```
|
||||
command terminated with exit code 1
|
||||
NODE2 cannot reach NODE1
|
||||
```
|
||||
|
||||
Cleanup the DaemonSet by running `kubectl delete ds/overlaytest`.
|
||||
|
||||
```
|
||||
|
||||
5. When this command has finished running, the output indicating everything is correct is:
|
||||
|
||||
```
|
||||
=> Start network overlay test
|
||||
=> End network overlay test
|
||||
```
|
||||
|
||||
If you see error in the output, that means that the [required ports]({{<baseurl>}}/rancher/v2.x/en/cluster-provisioning/node-requirements/#networking-requirements/) for overlay networking are not opened between the hosts indicated.
|
||||
|
||||
Example error output of a situation where NODE1 had the UDP ports blocked.
|
||||
|
||||
```
|
||||
=> Start network overlay test
|
||||
command terminated with exit code 1
|
||||
NODE2 cannot reach NODE1
|
||||
command terminated with exit code 1
|
||||
NODE3 cannot reach NODE1
|
||||
command terminated with exit code 1
|
||||
NODE1 cannot reach NODE2
|
||||
command terminated with exit code 1
|
||||
NODE1 cannot reach NODE3
|
||||
=> End network overlay test
|
||||
```
|
||||
|
||||
Cleanup the DaemonSet by running `kubectl delete ds/overlaytest`.
|
||||
If you see error in the output, there is some issue with the route between the pods on the two hosts. In the above output the node `wk2` has no connectivity over the overlay network. This could be because the [required ports]({{<baseurl>}}/rancher/v2.x/en/cluster-provisioning/node-requirements/#networking-requirements/) for overlay networking are not opened for `wk2`.
|
||||
6. You can now clean up the DaemonSet by running `kubectl delete ds/overlaytest`.
|
||||
|
||||
|
||||
### Check if MTU is correctly configured on hosts and on peering/tunnel appliances/devices
|
||||
|
||||
Reference in New Issue
Block a user