195 lines
6.7 KiB
Markdown
195 lines
6.7 KiB
Markdown
# 使用etcdctl访问kuberentes数据
|
||
|
||
Kubenretes1.6中使用etcd V3版本的API，使用`etcdctl`直接`ls`的话只能看到`/kube-centos`一个路径。需要在命令前加上`ETCDCTL_API=3`这个环境变量才能看到kuberentes在etcd中保存的数据。
|
||
|
||
```bash
|
||
ETCDCTL_API=3 etcdctl get /registry/namespaces/default -w=json|python -m json.tool
|
||
```
|
||
|
||
- `-w`指定输出格式
|
||
|
||
将得到这样的json的结果：
|
||
|
||
```json
|
||
{
|
||
"count": 1,
|
||
"header": {
|
||
"cluster_id": 12091028579527406772,
|
||
"member_id": 16557816780141026208,
|
||
"raft_term": 36,
|
||
"revision": 29253467
|
||
},
|
||
"kvs": [
|
||
{
|
||
"create_revision": 5,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvZGVmYXVsdA==",
|
||
"mod_revision": 5,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmIKSAoHZGVmYXVsdBIAGgAiACokZTU2YzMzMDgtMWVhOC0xMWU3LThjZDctZjRlOWQ0OWY4ZWQwMgA4AEILCIn4sscFEKOg9xd6ABIMCgprdWJlcm5ldGVzGggKBkFjdGl2ZRoAIgA=",
|
||
"version": 1
|
||
}
|
||
]
|
||
}
|
||
```
|
||
|
||
使用`--prefix`可以看到所有的子目录，如查看集群中的namespace：
|
||
|
||
```bash
|
||
ETCDCTL_API=3 etcdctl get /registry/namespaces --prefix -w=json|python -m json.tool
|
||
```
|
||
|
||
输出结果中可以看到所有的namespace。
|
||
|
||
```bash
|
||
{
|
||
"count": 8,
|
||
"header": {
|
||
"cluster_id": 12091028579527406772,
|
||
"member_id": 16557816780141026208,
|
||
"raft_term": 36,
|
||
"revision": 29253722
|
||
},
|
||
"kvs": [
|
||
{
|
||
"create_revision": 24310883,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvYXV0b21vZGVs",
|
||
"mod_revision": 24310883,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmQKSgoJYXV0b21vZGVsEgAaACIAKiQ1MjczOTU1ZC1iMzEyLTExZTctOTcwYy1mNGU5ZDQ5ZjhlZDAyADgAQgsI7fSWzwUQ6Jv1Z3oAEgwKCmt1YmVybmV0ZXMaCAoGQWN0aXZlGgAiAA==",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 21387676,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvYnJhbmQ=",
|
||
"mod_revision": 21387676,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmEKRwoFYnJhbmQSABoAIgAqJGNkZmQ1Y2NmLWExYzktMTFlNy05NzBjLWY0ZTlkNDlmOGVkMDIAOABCDAjR9qLOBRDYn83XAXoAEgwKCmt1YmVybmV0ZXMaCAoGQWN0aXZlGgAiAA==",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 5,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvZGVmYXVsdA==",
|
||
"mod_revision": 5,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmIKSAoHZGVmYXVsdBIAGgAiACokZTU2YzMzMDgtMWVhOC0xMWU3LThjZDctZjRlOWQ0OWY4ZWQwMgA4AEILCIn4sscFEKOg9xd6ABIMCgprdWJlcm5ldGVzGggKBkFjdGl2ZRoAIgA=",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 18504694,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvZGV2",
|
||
"mod_revision": 24310213,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmwKUgoDZGV2EgAaACIAKiQyOGRlMGVjNS04ZTEzLTExZTctOTcwYy1mNGU5ZDQ5ZjhlZDAyADgAQgwI89CezQUQ0v2fuQNaCwoEbmFtZRIDZGV2egASDAoKa3ViZXJuZXRlcxoICgZBY3RpdmUaACIA",
|
||
"version": 4
|
||
},
|
||
{
|
||
"create_revision": 10,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMva3ViZS1wdWJsaWM=",
|
||
"mod_revision": 10,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmcKTQoLa3ViZS1wdWJsaWMSABoAIgAqJGU1ZjhkY2I1LTFlYTgtMTFlNy04Y2Q3LWY0ZTlkNDlmOGVkMDIAOABCDAiJ+LLHBRDdrsDPA3oAEgwKCmt1YmVybmV0ZXMaCAoGQWN0aXZlGgAiAA==",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 2,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMva3ViZS1zeXN0ZW0=",
|
||
"mod_revision": 2,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEmYKTAoLa3ViZS1zeXN0ZW0SABoAIgAqJGU1NmFhMDVkLTFlYTgtMTFlNy04Y2Q3LWY0ZTlkNDlmOGVkMDIAOABCCwiJ+LLHBRDoq9ASegASDAoKa3ViZXJuZXRlcxoICgZBY3RpdmUaACIA",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 3774247,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMvc3BhcmstY2x1c3Rlcg==",
|
||
"mod_revision": 3774247,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEoABCmYKDXNwYXJrLWNsdXN0ZXISABoAIgAqJDMyNjY3ZDVjLTM0YWMtMTFlNy1iZmJkLThhZjFlM2E3YzViZDIAOABCDAiA1cbIBRDU3YuAAVoVCgRuYW1lEg1zcGFyay1jbHVzdGVyegASDAoKa3ViZXJuZXRlcxoICgZBY3RpdmUaACIA",
|
||
"version": 1
|
||
},
|
||
{
|
||
"create_revision": 15212191,
|
||
"key": "L3JlZ2lzdHJ5L25hbWVzcGFjZXMveWFybi1jbHVzdGVy",
|
||
"mod_revision": 15212191,
|
||
"value": "azhzAAoPCgJ2MRIJTmFtZXNwYWNlEn0KYwoMeWFybi1jbHVzdGVyEgAaACIAKiQ2YWNhNjk1Yi03N2Y5LTExZTctYmZiZC04YWYxZTNhN2M1YmQyADgAQgsI1qiKzAUQkoqxDloUCgRuYW1lEgx5YXJuLWNsdXN0ZXJ6ABIMCgprdWJlcm5ldGVzGggKBkFjdGl2ZRoAIgA=",
|
||
"version": 1
|
||
}
|
||
]
|
||
}
|
||
```
|
||
|
||
key的值是经过base64编码，需要解码后才能看到实际值，如：
|
||
|
||
```bash
|
||
$ echo L3JlZ2lzdHJ5L25hbWVzcGFjZXMvYXV0b21vZGVs|base64 -d
|
||
/registry/namespaces/automodel
|
||
```
|
||
|
||
## etcd中kubernetes的元数据
|
||
|
||
我们使用kubectl命令获取的kubernetes的对象状态实际上是保存在etcd中的，使用下面的脚本可以获取etcd中的所有kubernetes对象的key：
|
||
|
||
> 注意，我们使用了ETCD v3版本的客户端命令来访问etcd。
|
||
|
||
```bash
|
||
#!/bin/bash
|
||
# Get kubernetes keys from etcd
|
||
export ETCDCTL_API=3
|
||
keys=`etcdctl get /registry --prefix -w json|python -m json.tool|grep key|cut -d ":" -f2|tr -d '"'|tr -d ","`
|
||
for x in $keys;do
|
||
echo $x|base64 -d|sort
|
||
done
|
||
```
|
||
|
||
通过输出的结果我们可以看到kubernetes的原数据是按何种结构包括在kuberentes中的，输出结果如下所示：
|
||
|
||
```ini
|
||
/registry/ThirdPartyResourceData/istio.io/istioconfigs/default/route-rule-details-default
|
||
/registry/ThirdPartyResourceData/istio.io/istioconfigs/default/route-rule-productpage-default
|
||
/registry/ThirdPartyResourceData/istio.io/istioconfigs/default/route-rule-ratings-default
|
||
...
|
||
/registry/configmaps/default/namerctl-script
|
||
/registry/configmaps/default/namerd-config
|
||
/registry/configmaps/default/nginx-config
|
||
...
|
||
/registry/deployments/default/sdmk-page-sdmk
|
||
/registry/deployments/default/sdmk-payment-web
|
||
/registry/deployments/default/sdmk-report
|
||
...
|
||
```
|
||
|
||
我们可以看到所有的Kuberentes的所有元数据都保存在`/registry`目录下，下一层就是API对象类型（复数形式），再下一层是`namespace`，最后一层是对象的名字。
|
||
|
||
以下是etcd中存储的kubernetes所有的元数据类型：
|
||
|
||
```ini
|
||
ThirdPartyResourceData
|
||
apiextensions.k8s.io
|
||
apiregistration.k8s.io
|
||
certificatesigningrequests
|
||
clusterrolebindings
|
||
clusterroles
|
||
configmaps
|
||
controllerrevisions
|
||
controllers
|
||
daemonsets
|
||
deployments
|
||
events
|
||
horizontalpodautoscalers
|
||
ingress
|
||
limitranges
|
||
minions
|
||
monitoring.coreos.com
|
||
namespaces
|
||
persistentvolumeclaims
|
||
persistentvolumes
|
||
poddisruptionbudgets
|
||
pods
|
||
ranges
|
||
replicasets
|
||
resourcequotas
|
||
rolebindings
|
||
roles
|
||
secrets
|
||
serviceaccounts
|
||
services
|
||
statefulsets
|
||
storageclasses
|
||
thirdpartyresources
|
||
```
|
||
|
||
## 参考
|
||
|
||
- [etcd中文文档](https://github.com/doczhcn/etcd)
|
||
- [etcd官方文档](https://coreos.com/etcd/docs/latest/) |