Добрый день.

Подскажите как почистить эту таблицу.

в man conntrack смотрел

TABLES
       The connection tracking subsystem maintains two internal tables:

       conntrack:
              This is the default table.  It contains a list of all currently tracked connections through the system.  If you don’t use connection
              tracking exemptions (NOTRACK iptables target), this means all connections that go through the system.

       expect:
              This  is  the  table  of  expectations.   Connection tracking expectations are the mechanism used to "expect" RELATED connections to
              existing ones.  Expectations are generally used by "connection  tracking  helpers"  (sometimes  called  application  level  gateways
              [ALGs]) for more complex protocols such as FTP, SIP, H.323.

conntrack -F [table]

и как правильно ?

conntrack -F conntrack