# Emergency Channel

#### Scenarios

- Emergency Channel
  - If the maximum number of sessions for an instance has been reached and the instance cannot be logged in to, you can view and kill unnecessary sessions through the emergency channel.
  - Emergency channel is available to only RDS MySQL and GaussDB(for MySQL) instances currently, but not to self-built DB instances on ECSs and instances in the creating, frozen, or abnormal state.
  - Do not kill sessions unless you really need to. All your kill operations will be logged.
  - If your instance can be logged in to on the DAS console, log in to the instance and perform the required operations through Real-Time Sessions.
  - Sessions of sensitive users such as rdsadmin, rdsbackup, rdsmetric, and rdsRepl cannot be killed.
- History Logs

  On the History Logs tab page, you can view all your sessions killed through the emergency channel.

#### Prerequisites

The DB engine must be MySQL. The MySQL 5.6 version must be 5.6.43.3 or later, and MySQL 5.7 version must be 5.7.25.3 or later.

#### Procedure

1. Log in to the DAS console using your username and password.
2. On the Overview page, click Go to Intelligent O&M.
3. Select the required instance and click Details to go to the Intelligent O&M overview page.
4. Choose Sessions > Emergency Channel, and select the sessions you want to kill. Sessions are sorted in descending order by duration.
5. Click Kill. In the displayed dialog box, click Yes.
6. Click History Logs to view the sessions killed through the emergency channel.

Parent topic: Sessions