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Remove redirect from docs.

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Brendan Burns 2015-06-15 15:42:05 -07:00
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docs/accessing-the-cluster.md
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@ -1,7 +1,6 @@
# User Guide to Accessing the Cluster
* [Accessing the cluster API](#api)
* [Accessing services running on the cluster](#otherservices)
* [Requesting redirects](#redirect)
* [So many proxies](#somanyproxies)
## Accessing the cluster API<a name="api"></a>
@ -203,100 +202,7 @@ You may be able to put a apiserver proxy url into the address bar of a browser.
way that is unaware of the proxy path prefix.
## <a name="redirect"></a>Requesting redirects
Use a `redirect` request so that the server returns an HTTP redirect response and identifies the specific node and service that
can handle the request.
**Note**: Since the hostname or address that is returned is usually only accessible from inside the cluster,
sending `redirect` requests is useful only for code running inside the cluster. Also, keep in mind that any subsequent `redirect` requests to the same
server might return different results (because another node at that point in time can better serve the request).
**Tip**: Use a redirect request to reduce calls to the proxy server by first obtaining the address of a node on the
cluster and then using that returned address for all subsequent requests.
##### Example
To request a redirect and then verify the address that gets returned, let's run a query on `oban` (Google Compute Engine virtual machine). Note that `oban` is running in the same project and default network (Google Compute Engine) as the Kubernetes cluster.
To request a redirect for the Elasticsearch service, we can run the following `curl` command:
```
user@oban:~$ curl -L -k -u admin:4mty0Vl9nNFfwLJz https://104.197.5.247/api/v1/redirect/namespaces/default/services/elasticsearch-logging/
{
"status" : 200,
"name" : "Skin",
"cluster_name" : "kubernetes_logging",
"version" : {
"number" : "1.4.4",
"build_hash" : "c88f77ffc81301dfa9dfd81ca2232f09588bd512",
"build_timestamp" : "2015-02-19T13:05:36Z",
"build_snapshot" : false,
"lucene_version" : "4.10.3"
},
"tagline" : "You Know, for Search"
}
```
**Note**: We use the `-L` flag in the request so that `curl` follows the returned redirect address and retrieves the Elasticsearch service information.
If we examine the actual redirect header (instead run the same `curl` command with `-v`), we see that the request to `https://104.197.5.247/api/v1/redirect/namespaces/default/services/elasticsearch-logging/` is redirected to `http://10.244.2.7:9200`:
```
user@oban:~$ curl -v -k -u admin:4mty0Vl9nNFfwLJz https://104.197.5.247/api/v1/redirect/namespaces/default/services/elasticsearch-logging/
* About to connect() to 104.197.5.247 port 443 (#0)
* Trying 104.197.5.247...
* connected
* Connected to 104.197.5.247 (104.197.5.247) port 443 (#0)
* successfully set certificate verify locations:
* CAfile: none
CApath: /etc/ssl/certs
* SSLv3, TLS handshake, Client hello (1):
* SSLv3, TLS handshake, Server hello (2):
* SSLv3, TLS handshake, CERT (11):
* SSLv3, TLS handshake, Server key exchange (12):
* SSLv3, TLS handshake, Server finished (14):
* SSLv3, TLS handshake, Client key exchange (16):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSLv3, TLS change cipher, Client hello (1):
* SSLv3, TLS handshake, Finished (20):
* SSL connection using ECDHE-RSA-AES256-GCM-SHA384
* Server certificate:
* subject: CN=kubernetes-master
* start date: 2015-03-04 19:40:24 GMT
* expire date: 2025-03-01 19:40:24 GMT
* issuer: CN=104.197.5.247@1425498024
* SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.
* Server auth using Basic with user 'admin'
> GET /api/v1/redirect/namespaces/default/services/elasticsearch-logging HTTP/1.1
> Authorization: Basic YWRtaW46M210eTBWbDluTkZmd0xKeg==
> User-Agent: curl/7.26.0
> Host: 104.197.5.247
> Accept: */*
>
* additional stuff not fine transfer.c:1037: 0 0
* HTTP 1.1 or later with persistent connection, pipelining supported
< HTTP/1.1 307 Temporary Redirect
< Server: nginx/1.2.1
< Date: Thu, 05 Mar 2015 00:14:45 GMT
< Content-Type: text/plain; charset=utf-8
< Content-Length: 0
< Connection: keep-alive
< Location: http://10.244.2.7:9200
<
* Connection #0 to host 104.197.5.247 left intact
* Closing connection #0
* SSLv3, TLS alert, Client hello (1):
```
We can also run the `kubectl get pods` command to view a list of the pods on the cluster and verify that `http://10.244.2.7` is where the Elasticsearch service is running:
```
$ kubectl get pods
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED
elasticsearch-logging-controller-gziey 10.244.2.7 elasticsearch-logging kubernetes/elasticsearch:1.0 kubernetes-minion-hqhv.c.kubernetes-user2.internal/104.154.33.252 kubernetes.io/cluster-service=true,name=elasticsearch-logging Running 5 hours
kibana-logging-controller-ls6k1 10.244.1.9 kibana-logging kubernetes/kibana:1.1 kubernetes-minion-h5kt.c.kubernetes-user2.internal/146.148.80.37 kubernetes.io/cluster-service=true,name=kibana-logging Running 5 hours
kube-dns-oh43e 10.244.1.10 etcd quay.io/coreos/etcd:v2.0.3 kubernetes-minion-h5kt.c.kubernetes-user2.internal/146.148.80.37 k8s-app=kube-dns,kubernetes.io/cluster-service=true,name=kube-dns Running 5 hours
kube2sky kubernetes/kube2sky:1.0
skydns kubernetes/skydns:2014-12-23-001
monitoring-heapster-controller-fplln 10.244.0.4 heapster kubernetes/heapster:v0.8 kubernetes-minion-2il2.c.kubernetes-user2.internal/130.211.155.16 kubernetes.io/cluster-service=true,name=heapster,uses=monitoring-influxdb Running 5 hours
monitoring-influx-grafana-controller-0133o 10.244.3.4 influxdb kubernetes/heapster_influxdb:v0.3 kubernetes-minion-kmin.c.kubernetes-user2.internal/130.211.173.22 kubernetes.io/cluster-service=true,name=influxGrafana Running 5 hours
grafana kubernetes/heapster_grafana:v0.4
```
The redirect capabilities have been deprecated and removed. Please use a proxy (see below) instead.
##<a name="somanyproxies"></a>So Many Proxies
There are several different proxies you may encounter when using kubernetes: