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Forum Discussion

Michael_107360's avatar
Michael_107360
Icon for Cirrus rankCirrus
Feb 10, 2017

Fastl4 TCP Profile Best Practice

Fastl4 TCP Profile Recommendations:   I have seen conflicting recommendations concerning the Forwarding Virtual Server. and the Settings for the TCP Fastl4 profile. Goal is to do nothing more than...
application delivery
LTM
TMOS
Chris_Grant's avatar
Chris_Grant
Icon for Employee rankEmployee
Feb 10, 2017

It really depends on how you want the BigIP to handle non-SYN packets. If you have loose initialization enabled, and we get a PSH, ACK out of the blue with no connection in the connection table, we will forward that packet on.

 

If you disable loose initialization, that same PSH, ACK will either be dropped or reset depending on your settings (by default we should reset).

 

Basically if you want the BigIP to just push packets around without paying much attention to what's in them, loose initialization and loose close will do that for you. Note that you lose a lot of the functionality that makes the BigIP cool by doing this.