# 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) DB databases currently, but not to self-built databases on ECSs and instances in the creating, frozen, or abnormal state.
  - Use this function in urgent conditions. All your kill operations will be recorded in logs.
  - If your instance can be logged in to on the DAS console, log in to the instance and perform desired operations through Real-Time Sessions.
  - Sessions of sensitive users, like 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. Locate your desired instance and click Details to go to the Intelligent O&M overview page.
4. On the Emergency Channel tab page, select the sessions you want to kill. By default, the sessions are sorted in descending order by session duration.
5. Click Kill. In the displayed dialog box, click Yes.
6. On the History Logs tab page, view your sessions killed through the emergency channel.

Parent topic: Sessions