The Connections Command - D-Link NetDefendOS User Manual

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output will show two percentages instead of one. The first percentage is the load for the CPU
core that is running most of NetDefendOS. The second percentage shows the load for the CPU
core that is running the interface polling subsystem. An example of this output is shown below:
CPU Load
Poll offloading is turned on automatically by NetDefendOS if the hardware platform supports it
and the administrator does not need to enable it.

2.6.4. The connections Command

By using the connections command, the administrator can get a snapshot of all the connections
currently set up in the NetDefendOS state engine. The command can be abbreviated to conn and
some example output is shown below:
gw-world:/> conn
State
Proto
-------- ------- --------------------------- ----------------------- ------
TCP_OPEN TCP
UDP
UDP
PING
ICMP
FIN_RCVD TCP
TCP_OPEN TCP
UDP
UDP
UDP
UDP
Each line in the command's output corresponds to a single connection. The fields shown are:
State
This indicates the state of the connection and is only really relevant to TCP connections
where different states apply. Some of the possible values are:
i.
UDP - A UDP pseudo-connection.
ii.
PING - AN ICMP ping connection.
iii.
TCP_OPEN - A TCP connection is opening.
iv.
SYN_RCVD - A TCP connection has received a SYN packet and is open.
v.
FIN_RCVD - A TCP connection has been closed. Connections wait, by default, for 80
seconds before all data is cleaned up by NetDefendOS so that the connection could be
reopened. The 80 second value is controlled by the NetDefendOS setting TCP FIN Idle
Lifetime. The ability to reopen a connection is controlled by the NetDefendOS setting
Allow TCP Reopen which is disabled by default.
vi.
RAW IP - Another protocol which is identified in the Protocol column.
Proto
The protocol used for the connection and can be the same as the State column is some cases.
Some of the possible values are:
i.
UDP - A UDP pseudo-connection.
ii.
ICMP - AN ICMP ping connection.
iii.
TCP - A TCP connection.
iv.
ESP - Used for IPsec VPN tunnels.
: 12%, 1%
Source
If1:10.4.4.24:54047
If2:192.168.109.11:4500
vlan1:192.168.1.1:512
If1:10.4.4.121:55679
If2:192.168.96.77:35217
vlan1:192.168.100.163:560
vlan1:192.168.100.163:582
123
Chapter 2: Management and Maintenance
Destination
If2:192.168.9.3:338
If3:10.152.0.22:450
If3:90.152.1.1:512
core:10.4.0.31:444
If3:10.93.2.49:463
vpn-A:10.45.1.2:161
vpn-B:10.25.1.2:161
Tmout
261772
130
8
69
70855
9
76

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