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What_Lies_Bene1's avatar
What_Lies_Bene1
Icon for Cirrostratus rankCirrostratus
Dec 31, 2012

TCP Profile > Zero Window Timeout

Another one for you all. The TCP Profile Zero Window Timeout setting description states "If the Zero Window Timeout timer elapses, the BIG-IP system terminates the connection."   Does this mean a ...
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nitass_89166's avatar
nitass_89166
Icon for Noctilucent rankNoctilucent

Hence, the sending of a RST on Zero Window timeout cannot be controlled?

you do not want to have reset when zero window timeout is reached, do you?

if so, is setting it to indefinite (4294967295 ms) usable?

root@(ve11a)(cfg-sync In Sync)(Standby)(/Common)(tmos) list ltm profile tcp mytcp
ltm profile tcp mytcp {
    app-service none
    defaults-from tcp
    zero-window-timeout 4294967295
}
Gladius_116564's avatar
Gladius_116564
Historic F5 Account
Aug 15, 2014
Nitass, I wouldn't recommend this, since F5 has to keep the tcp payload in it's butter that it might have received from the server. Multiple concurrent open tcp zerowindow connections can fill the F5 buffer. I would say that it is not normal that a client can be in ZeroWindow state for more than 20 secs.