What Should I Do If Error Message "read: Connection reset by peer" Is Displayed When I Remotely Log In to a Linux ECS?

Symptom

When I attempted to remotely log in to a Linux ECS, the system displayed error message "read: Connection reset by peer".

**Figure 1** read: Connection reset by peer

Figure 1 read: Connection reset by peer

Possible Causes

  • The remote login port is not permitted in the security group.

  • The firewall is enabled on the ECS, but the remote login port is blocked by the firewall.

Solution

Perform the following operations for troubleshooting:

  • Check security group rules.

    • Inbound: Add the remote login port. The default port 22 is used as an example.

    • Outbound: Outbound rules allow network traffic to be out of specified ports.

  • Add a port to the ECS firewall exception.

    The following uses Ubuntu as an example:

    1. Run the following command to view the firewall status:

      sudo ufw status

      The following information is displayed:

      Status: active
      
    2. Add a port to the firewall exception, taking the default port 22 as an example.

      ufw allow 22

      Rule added

      Rule added (v6)

    3. Run following command to check the firewall status again:

      sudo ufw status

      Status: active
      To                         Action      From
      --                         ------      ----
      22                         ALLOW       Anywhere
      22 (v6)                    ALLOW       Anywhere (v6)
      

      Try to remotely log in to the ECS again.