(
Optional
) Set the
Interval (sec)
(in
seconds) between keepalive packets that the local end of the GRE
tunnel sends to the tunnel peer. This is also the interval that,
when multiplied by the
Hold Timer
, is the
length of time that the firewall must see successful keepalive packets before
the GRE tunnel comes back up (range is 1 to 50; default is 10).
Setting an interval too small will cause many keepalive packets
that might be unnecessary in your environment and will require extra
bandwidth and processing. Setting an interval too large can delay
failover because error conditions might not be identified immediately.