ZyXEL Communications P-660N-T1A, User Manual

Page: 209 / 322

Chapter 20 Logs
P-660N-T1A User’s Guide
209
Table 76 TCP Reset Logs
LOG MESSAGE DESCRIPTION
Under SYN flood attack,
sent TCP RST
The router sent a TCP reset packet when a host was
under a SYN flood attack (the TCP incomplete count is per
destination host.)
Exceed TCP MAX
incomplete, sent TCP RST
The router sent a TCP reset packet when the number of
TCP incomplete connections exceeded the user configured
threshold. (the TCP incomplete count is per destination
host.) Note: Refer to
TCP Maximum Incomplete in the
Firewall Attack Alerts screen.
Peer TCP state out of
order, sent TCP RST
The router sent a TCP reset packet when a TCP
connection state was out of order.Note: The firewall refers
to RFC793 Figure 6 to check the TCP state.
Firewall session time
out, sent TCP RST
The router sent a TCP reset packet when a dynamic
firewall session timed out.Default timeout values:ICMP
idle timeout (s): 60UDP idle timeout (s): 60TCP
connection (three way handshaking) timeout (s): 30TCP
FIN-wait timeout (s): 60TCP idle (established) timeout
(s): 3600
Exceed MAX incomplete,
sent TCP RST
The router sent a TCP reset packet when the number of
incomplete connections (TCP and UDP) exceeded the
user-configured threshold. (Incomplete count is for all
TCP and UDP connections through the firewall.)Note:
When the number of incomplete connections (TCP + UDP)
> “Maximum Incomplete High”, the router sends TCP RST
packets for TCP connections and destroys TOS (firewall
dynamic sessions) until incomplete connections <
“Maximum Incomplete Low”.
Access block, sent TCP
RST
The router sends a TCP RST packet and generates this log
if you turn on the firewall TCP reset mechanism (via CI
command: "sys firewall tcprst").
Table 77 Packet Filter Logs
LOG MESSAGE DESCRIPTION
[ TCP | UDP | ICMP | IGMP |
Generic ] packet filter
matched (set: %d, rule: %d)
Attempted access matched a configured filter rule
(denoted by its set and rule number) and was blocked
or forwarded according to the rule.