長時間沒有操做putty就會斷開鏈接是怎麼回事?

 

 

 

seconds between keepalives 設置爲10就行了， 這個值有什麼含義，服務器爲了節省資源採起了一些措施，其中一條就是若是檢測一個會話(session)幾分鐘或者幾小時沒有數據流入或者流出就會斷開這個連接，佔着茅坑不拉屎就是說這種狀況，設置了putty中keepalive這個值以後好比是10，那putty每隔10秒就給服務器發送一個空數據包，以此來表示我還沒拉完屎呢?這樣廁所看管員就不會把咱們踢出去了。

我這裏找到了putty官方網站中關於keepalive的說明：

4.13 The Connection panel

The Connection panel allows you to configure options that apply to more than one type of connection.

4.13.1 Using keepalives to prevent disconnection

If you find your sessions are closing unexpectedly (most often with ‘Connection reset by peer’) after they have been idle for a while, you might want to try using this option.

Some network routers and firewalls need to keep track of all connections through them. Usually, these firewalls will assume a connection is dead if no data is transferred in either direction after a certain time interval. This can cause PuTTY sessions to be unexpectedly closed by the firewall if no traffic is seen in the session for some time.

The keepalive option (‘Seconds between keepalives’) allows you to configure PuTTY to send data through the session at regular intervals, in a way that does not disrupt the actual terminal session. If you find your firewall is cutting idle connections off, you can try entering a non-zero value in this field. The value is measured in seconds; so, for example, if your firewall cuts connections off after ten minutes then you might want to enter 300 seconds (5 minutes) in the box.

Note that keepalives are not always helpful. They help if you have a firewall which drops your connection after an idle period; but if the network between you and the server suffers from breaks in connectivity then keepalives can actually make things worse. If a session is idle, and connectivity is temporarily lost between the endpoints, but the connectivity is restored before either side tries to send anything, then there will be no problem - neither endpoint will notice that anything was wrong. However, if one side does send something during the break, it will repeatedly try to re-send, and eventually give up and abandon the connection. Then when connectivity is restored, the other side will find that the first side doesn't believe there is an open connection any more. Keepalives can make this sort of problem worse, because they increase the probability that PuTTY will attempt to send data during a break in connectivity. (Other types of periodic network activity can cause this behaviour; in particular, SSH-2 re-keys can have this effect. See section 4.19.2.)

 

 

在用navicat遠程鏈接數據庫以後，一段時間沒有操做也會有斷開鏈接這種狀況，原理和putty的設置是同樣的，在鏈接的高級設置裏面有個keep alive 設置爲10或者20就行。