Ohara: UI cannot add ohara node

[HarryChiang143]

Describe the bug
透過Ohara Manager UI 新增 Ohara nodes失敗，並產生 Unsupported Content-Type, supported: application/json Error exception

To Reproduce
Steps the behavior:

1. 安裝k8s master
2. 安裝k8s agent
3. 透過docker command 啟動configurator
4. 透過docker command 啟動manager
5. 透過UI新增節點 > Got Exception

Screenshots

Operation System :

• Backend OS & Version: [CentOS 7.6]
• Frontend OS & Version: [CentOS 7.6]
• Browser & Version [Chrome 72.0.3626.119 64bit]

Additional context
none.

[konekoya]

After some investigation with @chia7712 and @jackyoh. This error is originated from k8s and not related to our UI. Cc @jackyoh for further investigation :)

[jackyoh]

以上的問題主要是在重新 reset k8s 環境時沒有先把 k8s api server 重新啟動, 造成連不到 k8s api server 的問題. 我會在 k8s 安裝的 README.md 再補充 reset k8s 環境時所要的連結.

[HarryChiang143]

The root cause of this issue was that the old DNS server hadn't been closed when I was installing a new version of ohara stream. Therefore, if you already have an older version of ohara stream running on your machines. Make sure the 8080 port is no being use before installing a newer version of ohara stream.

You can simply kill the process running on port 8080 by:

sudo lsof -i:8080 # see if the port is being use

If the port is in use. Kill it with:

sudo kill -9 ${PID}