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update service debug doc from user feedback

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Tim Hockin 2015-07-15 11:29:24 -07:00
parent 596a8a40d1
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docs/user-guide/debugging-services.md
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@ -116,7 +116,9 @@ $ kubectl exec -ti busybox-sleep sh
## Setup ## Setup
For the purposes of this walk-through, let's run some `Pod`s. For the purposes of this walk-through, let's run some `Pod`s. Since you're
probably debugging your own `Service` you can substitute your own details, or you
can follow along and get a second data point.
```sh ```sh
$ kubectl run hostnames --image=gcr.io/google_containers/serve_hostname \ $ kubectl run hostnames --image=gcr.io/google_containers/serve_hostname \
@ -191,7 +193,8 @@ $ kubectl get svc hostnames
Error from server: service "hostnames" not found Error from server: service "hostnames" not found
``` ```
So we have a culprit, let's create the `Service`: So we have a culprit, let's create the `Service`. As before, this is for the
walk-through - you can use your own `Service`'s details here.
```sh ```sh
$ kubectl expose rc hostnames --port=80 --target-port=9376 $ kubectl expose rc hostnames --port=80 --target-port=9376
@ -235,11 +238,11 @@ pod$ nslookup hostnames
Server: 10.0.0.10 Server: 10.0.0.10
Address: 10.0.0.10#53 Address: 10.0.0.10#53
Name: hostnames.default.svc.cluster.local Name: hostnames
Address: 10.0.1.175 Address: 10.0.1.175
``` ```
If this fails, perhaps because your `Pod` and `Service` are in different If this fails, perhaps your `Pod` and `Service` are in different
`Namespace`s, try a namespace-qualified name: `Namespace`s, try a namespace-qualified name:
```sh ```sh
@ -247,11 +250,12 @@ pod$ nslookup hostnames.default
Server: 10.0.0.10 Server: 10.0.0.10
Address: 10.0.0.10#53 Address: 10.0.0.10#53
Name: hostnames.default.svc.cluster.local Name: hostnames.default
Address: 10.0.1.175 Address: 10.0.1.175
``` ```
If this still fails, try a fully-qualified name: If this works, you'll need to ensure that `Pod`s and `Service`s run in the same
`Namespace`. If this still fails, try a fully-qualified name:
```sh ```sh
pod$ nslookup hostnames.default.svc.cluster.local pod$ nslookup hostnames.default.svc.cluster.local
@ -262,6 +266,10 @@ Name: hostnames.default.svc.cluster.local
Address: 10.0.1.175 Address: 10.0.1.175
``` ```
Note the suffix here: "default.svc.cluster.local". The "default" is the
`Namespace` we're operating in. The "svc" denotes that this is a `Service`.
The "cluster.local" is your cluster domain.
You can also try this from a `Node` in the cluster (note: 10.0.0.10 is my DNS You can also try this from a `Node` in the cluster (note: 10.0.0.10 is my DNS
`Service`): `Service`):
@ -278,8 +286,8 @@ If you are able to do a fully-qualified name lookup but not a relative one, you
need to check that your `kubelet` is running with the right flags. need to check that your `kubelet` is running with the right flags.
The `--cluster_dns` flag needs to point to your DNS `Service`'s IP and the The `--cluster_dns` flag needs to point to your DNS `Service`'s IP and the
`--cluster_domain` flag needs to be your cluster's domain - we assumed `--cluster_domain` flag needs to be your cluster's domain - we assumed
"cluster.local" in this document, but your might be different, in which case "cluster.local" in this document, but yours might be different, in which case
you should change that in all of the commands. you should change that in all of the commands above.
### Does any Service exist in DNS? ### Does any Service exist in DNS?