OPENMARU Cloud APM Docs

2.5.5 System - Network

System > Network > TCP Connection Status

Displays the system-wide Network TCP connection status information in a graph.

Each item looks like this

Item	Description
LISTEN	The port is open and waiting for a connection request so it can receive the request.
SYN_SENT	The local has attempted to remotely signal a connection request (SYN).
SYN_RECV	Connection request received from the remote The request was received and responded with SYN and ACK signals, but no ACK was received. If there are a lot of SYN_RECVs, you can suspect a TCP SYNC Flooding attack.
ESTABLISHED	Still connected to each other.
FIN_WAIT1	The socket is closed and the connection is being terminated, but you can still receive responses from the remote.
FIN_WAIT2	The local connection is waiting for a request to close the connection from the remote.
CLOSE_WAIT	The local connection has received a remote connection request and is waiting for the connection to be closed. FIN and ACK signals are received from the remote and an ACK is sent to the remote.
TIME_WAIT	The connection is closed but waiting for an acknowledgment signal from the remote. You will see this value a lot when Apache has KeepAlive turned off.
LAST_ACK	The connection is closed and waiting for an acknowledgment.
CLOSE	The connection is completely closed.
CLOSING	Connection closed but data was lost in transit
UNKNOWN	The socket status is unknown.

Item

Description

LISTEN

The port is open and waiting for a connection request so it can receive the request.

SYN_SENT

The local has attempted to remotely signal a connection request (SYN).

SYN_RECV

Connection request received from the remote

The request was received and responded with SYN and ACK signals, but no ACK was received. If there are a lot of SYN_RECVs, you can suspect a TCP SYNC Flooding attack.

ESTABLISHED

Still connected to each other.

FIN_WAIT1

The socket is closed and the connection is being terminated, but you can still receive responses from the remote.

FIN_WAIT2

The local connection is waiting for a request to close the connection from the remote.

CLOSE_WAIT

The local connection has received a remote connection request and is waiting for the connection to be closed.

FIN and ACK signals are received from the remote and an ACK is sent to the remote.

TIME_WAIT

The connection is closed but waiting for an acknowledgment signal from the remote.

You will see this value a lot when Apache has KeepAlive turned off.

LAST_ACK

The connection is closed and waiting for an acknowledgment.

The connection is completely closed.

CLOSING

Connection closed but data was lost in transit

UNKNOWN

The socket status is unknown.

System > Network > Traffic

Graphically displays the number of send and receive bytes per second of data for each network interface card in the system.

System > Network > Transmission Packets

Graphs the number of send/receive packets per second of data for each network interface card in the system.

System > Network > Packet Errors

Graphs the number of packet errors per second of data for each network interface card in the system.

If you are experiencing packet errors or drops, it is likely that you are experiencing excessive network load. It is recommended to check the network or operating system kernel parameters (network related).