Can http monitor use Keep-Alive?

Question

Is the connection reused when specified "Connection:Keep-Alive"?&nbsp;
&nbsp;Should I specify "Connection:Close"?&nbsp;&nbsp;

hoolio · Answer

Yes, and yes.  To close the connection, you can use a send string like this:&nbsp;
&nbsp;GET /path/to/file.html
Host: example.com
Connection: close
&nbsp;
&nbsp;Aaron

taro_112311 · Answer

Is it correct in the following understanding?&nbsp;
&nbsp;Specifying "Connection:Keep-Alive" is efficient, because the connection established first keeps being used.&nbsp;&nbsp;

hoolio · Answer

Sorry, I mis-read your original question.  I know that the connection to the server can be kept open if the Connection: close isn't used, and that this can leave connections open for longer than necessary, but I don't know whether LTM would ever re-use it if it's still open.  I'll try testing to see.&nbsp;
&nbsp;Aaron

hoolio · Answer

Testing on 9.2.x, I see LTM selecting a new port regardless of the send string configuration, which I guess follows with the recommendation to use the Connection: close header to tell the server to close the TCP connection.&nbsp;
&nbsp;Aaron

deb_allen_18 · Answer

Thanks for clarifying, Aaron.&nbsp;
&nbsp;It was my understanding as well that LTM would not re-use a monitor connection even if it was specified as a Keep-Alive connection.&nbsp;
&nbsp;Best practice is to specify either HTTP 1.0 or Connection: Keep-Alive to keep the connection to the server from remaining open longer than necessary.&nbsp;
&nbsp;/deb

Forum Discussion

Can http monitor use Keep-Alive?

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