Node Metrics in Network Dashboard and Metric Browser

The Network Agent collects various TCP socket metrics at the host level for the local node on which it is installed. Use these metrics to monitor the TCP stack health, collisions, and errors on all the physical interfaces, and CPU consumption of the Network Agent.

TCP Socket Metrics in the Network Dashboard

These metrics measure the overall TCP socket health of an individual node. To view these metrics, select a node: access the Network Dashboard, click a tier, select the Nodes tab, and select the node of interest. The TCP Socket metrics for the selected node appear on the right side of the dashboard.

MetricDescriptionDefault Monitoring Mode

Established

The number of sockets that are in the established state

KPI

Embryonic

The number of sockets that are in the process of being set upKPI

Wait

The number of sockets that are unavailable for new connections because they are in the process of being closed. When a socket sends a Connection Close (FIN) message, the socket goes through three states:

  1. FIN_WAIT1 – Socket has sent the FIN and is waiting for an ACK from the remote socket
  2. FIN_WAIT2 – Socket receives ACK, and waits for FIN (final connection close) from the remote socket
  3. TIME_WAIT – The socket remains open to handle any packets for the TCP connection that might still be in the network. The TIME_WAIT state can last from one to four minutes, depending on the implementation.

A WAIT socket can result in significant delays or errors for the application, or service, that relies on that socket. Many simultaneous WAIT sockets can prevent applications and services from creating new connections.

KPI

Time Wait

The FIN_WAIT states are relatively short (in milliseconds), while the TIME_WAIT state is relatively long (one to four minutes). As a result, the Wait and Time Wait metrics should be fairly similar. Significant differences indicate a significant network or other delays between the selected node and another host.

KPI

Interface Metrics in the Metric Browser

These metrics measure the number of collisions and errors on the physical interfaces of the node. To view these metrics, drill down in the Metric Browser by selecting:

Application Infrastructure Performance > <tier-name> > Individual Nodes > <node-name> > Host > Interface

Monitoring Mode

#Collisions

Number of collision errors seen on all the interfaces, when an interface was blocked from sending a frame due to an Ethernet collision detectionKPI

#Receive Drops

Number of packets dropped while receiving by all interfaces on the hostKPI

#Receive Errors

Number of collision errors seen on all the interfaces, when an interface could not receive a frame due to a physical problem on the interface or the connected cableKPI

#Transmit Drops

Number of packets dropped while transmitting by all interfaces on the hostKPI

#Transmit Errors

Number of collision errors seen on all the interfaces, when an interface could not send a frame due to a physical problem on the interface or the connected cableKPI

#Total Errors

The total number of Ethernet or physical errors detected on the interfaceKPI

TCP Socket Metrics in the Network Dashboard

These metrics measure the overall TCP socket health of an individual node. To view these metrics, select a node: access the Network Dashboard, click a tier, select the Nodes tab, and select the node of interest. The TCP Socket metrics for the selected node appear on the right side of the dashboard.

Metric Description Default Monitoring Mode

Established

The number of sockets that are in the established state

 KPI

Embryonic

The number of sockets that are in the process of being set up KPI

Wait

The number of sockets that are unavailable for new connections because they are in the process of being closed. When a socket sends a Connection Close (FIN) message, the socket goes through three states:

  1. FIN_WAIT1 – Socket has sent the FIN and is waiting for an ACK from the remote socket
  2. FIN_WAIT2 – Socket receives ACK, and waits for FIN (final connection close) from the remote socket
  3. TIME_WAIT – The socket remains open to handle any packets for the TCP connection that might still be in the network. The TIME_WAIT state can last from one to four minutes, depending on the implementation.

A WAIT socket can result in significant delays or errors for the application, or service, that relies on that socket. Many simultaneous WAIT sockets can prevent applications and services from creating new connections.

 KPI

Time Wait

The FIN_WAIT states are relatively short (in milliseconds), while the TIME_WAIT state is relatively long (one to four minutes). As a result, the Wait and Time Wait metrics should be fairly similar. Significant differences indicate a significant network or other delays between the selected node and another host.

 KPI

Interface Metrics in the Metric Browser

These metrics measure the number of collisions and errors on the physical interfaces of the node. To view these metrics, drill down in the Metric Browser by selecting:

Application Infrastructure Performance > <tier-name> > Individual Nodes > <node-name> > Host > Interface

Monitoring Mode

#Collisions

Number of collision errors seen on all the interfaces, when an interface was blocked from sending a frame due to an Ethernet collision detectionKPI

#Receive Drops

Number of packets dropped while receiving by all interfaces on the hostKPI

#Receive Errors

Number of collision errors seen on all the interfaces, when an interface could not receive a frame due to a physical problem on the interface or the connected cableKPI

#Transmit Drops

Number of packets dropped while transmitting by all interfaces on the hostKPI

#Transmit Errors

Number of collision errors seen on all the interfaces, when an interface could not send a frame due to a physical problem on the interface or the connected cableKPI

#Total Errors

The total number of Ethernet or physical errors detected on the interfaceKPI