What is ClientAliveInterval in ssh?

ClientAliveInterval – This indicates the timeout in seconds. After x number of seconds, ssh server will send a message to the client asking for response. Deafult is 0 (server will not send message to client to check.).

What does ClientAliveCountMax 0 mean?

Setting a zero ClientAliveCountMax disables connection termination. ClientAliveInterval. Sets a timeout interval in seconds after which if no data has been received from the client, sshd(8) will send a message through the encrypted channel to request a response from the client.

What does X11UseLocalhost mean?

X11UseLocalhost. Specifies whether sshd should bind the X11 forwarding server to the loopback address or to the wildcard address. By default, sshd binds the forwarding server to the loopback address and sets the hostname part of the DISPLAY environment variable to “localhost”.

What is Gssapi authentication in ssh?

GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system’s GSSAPI to remote hosts, increasing the attack surface of the system. GSSAPI authentication must be disabled unless needed.

How do I stop SSH from disconnecting?

Avoid SSH timeout from the server

1. Edit SSHd configuration file using your favorite editor. $ sudo vi /etc/ssh/sshd_config.
2. Set these options as the followings: TCPKeepAlive no ClientAliveInterval 30 ClientAliveCountMax 240.
3. Restart the SSHd service.

How do I stop SSH connection timing out?

Option 1) Server Side Keep Alive

1. Log in as root.
2. Edit the file at /etc/ssh/sshd_config.
3. Add this line to the file: ClientAliveInterval 60.
4. Save the file.
5. Restart sshd on the server.

What is ControlPersist in ssh?

In contrast, with ControlPersist set, the master connection will remain open for the specified number of seconds after your last SSH session on that connection has exited. This is especially useful for tasks such as pushing to Github, which occur frequently but where any one session is short-lived.

How do I keep my ssh connection alive?

Keeping SSH connections alive

1. Start PuTTY.
2. Load your connection session.
3. In the Category pane, click Connection.
4. Under Sending of null packets to keep session active, in the Seconds between keepalives, type 240.
5. In the Category pane, click Session.
6. Click Save.
7. Connect to your account and monitor the connection.

What is OpenSSH server used for?

OpenSSH provides a server daemon and client tools to facilitate secure, encrypted remote control and file transfer operations, effectively replacing the legacy tools. The OpenSSH server component, sshd, listens continuously for client connections from any of the client tools.

What is MaxStartups in SSH?

The MaxStartups setting specifies the maximum number of concurrent unauthenticated connections to the SSH daemon. Additional connections are dropped until authentication succeeds or the LoginGraceTime expires for a connection.

How do I enable GSSAPI authentication?

For SSH client machines, modify the /etc/ssh/ssh_config file to enable the GSSAPI option GSSAPIAuthentication. It is a good idea to also enable option GSSAPIKeyExchange, so that server authentication can be done with GSS-API key exchange if supported by the server.

How do I disable GSSAPI?

Steps to disable or enable GSSAPI authentication in SSH: Open SSHd configuration file using your favorite text editor. $ sudo vi /etc/ssh/sshd_config [sudo] password for user: Search for GSSAPIAuthentication directive and set the value to no to disable GSSAPIAuthentication authentication method or yes to enable.