Re: TCP Keepalives Problem on Linux

olssons@xxxxxxxxx wrote:
What I have found is this:

If during the period when 2 connection hosts are physically
disconnected (ie cable pull), the client (Host-A) attempts to send
*any* data on the connection (even 1 byte), TCP keepalives stop
functioning and will never cause the connection to drop... even if
no more data is ever sent or received on the connection.

By definition, from the perspective of HostA when that single byte is
sent and remains unACKed, the connection remains "active" rather than
idle so the keepalives should not start. The connection will be
timed-out based on the "normal" retransmission mechanisms.

Only when/if there is no outstanding data on a connection should a
keepalive timer fire.

rick jones
--
The glass is neither half-empty nor half-full. The glass has a leak.
The real question is "Can it be patched?"
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
.

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