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What is ServerAliveInterval?
ServerAliveInterval. Sets a timeout interval in seconds after which if no data has been received from the server, ssh(1) will send a message through the encrypted channel to request a response from the server.
What is ClientAliveInterval and ClientAliveCountMax?
ClientAliveCountMax – This indicates the total number of checkalive message sent by the ssh server without getting any response from the ssh client. Default is 3. ClientAliveInterval – This indicates the timeout in seconds. After x number of seconds, ssh server will send a message to the client asking for response.
What is default ClientAliveInterval?
The default value is 3. If ClientAliveInterval is set to 15, and ClientAliveCountMax is left at the default, unresponsive SSH clients will be disconnected after approximately 45 seconds.
What is TCPKeepAlive in ssh?
The KEEPALIVE option of the TCP/IP Protocol ensures that connections are kept alive even while they are idle. When a connection to a client is inactive for a period of time (the timeout period), the operating system sends KEEPALIVE packets at regular intervals.
How do I enable SSH to keep alive?
Keeping SSH connections alive
- Start PuTTY.
- Load your connection session.
- In the Category pane, click Connection.
- Under Sending of null packets to keep session active, in the Seconds between keepalives, type 240.
- In the Category pane, click Session.
- Click Save.
- Connect to your account and monitor the connection.
What is SSH UsePrivilegeSeparation?
UsePrivilegeSeparation. Specifies whether sshd(8) separates privileges by creating an unprivileged child process to deal with incoming network traffic. After successful authentication, another process will be created that has the privilege of the authenticated user.
What is the default timeout for serveraliveinterval?
ServerAliveInterval Sets a timeout interval in seconds after which if no data has been received from the server, ssh will send a message through the encrypted channel to request a response from the server. The default is 0, indicating that these messages will not be sent to the server. This option applies to protocol version 2 only.
What is the default value for serveraliveinterval in SSH?
The default value is 3. If, for example, ServerAliveInterval is set to 15 and ServerAliveCountMax is left at the default, if the server becomes unresponsive, ssh will disconnect after approximately 45 seconds. This option applies to protocol version 2 only. Based on above, 0 means it’s disabled.
What is the default value for clientalivecountmax?
ClientAliveCountMax on the server side might also help. This is the limit of how long a client are allowed to stay unresponsive before being disconnected. The default value is 3, as in three ClientAliveInterval. This is explained in sshd_config manual ( man sshd_config ):
What is the difference between client and serveraliveinterval?
ServerAliveInterval: number of seconds that the clientwill wait before sending a null packet to the server (to keep the connection alive). ClientAliveInterval: number of seconds that the serverwill wait before sending a null packet to the client (to keep the connection alive).