Document revision date: 30 March 2001

When you click the Cluster Summary tab on an OpenVMS Node Summary page, the Availability Manager displays the OpenVMS Cluster Summary page (Figure 3-18).

This page contains cluster interconnect information for an entire cluster as well as detailed information about each node in the cluster, including System Communications Services (SCS) connections and LAN virtual circuits for individual nodes. The data items shown on the page correspond to data that the Show Cluster utility (SHOW CLUSTER) displays for the SYSTEMS and MEMBERS classes.

Figure 3-18 OpenVMS Cluster Summary Page

The two panes in the Cluster Summary page display the following information:

• The Summary pane (top) displays summary information about the entire cluster.
• The Cluster Members pane (bottom) displays detailed information about each node in the cluster, including its System Communication Architecture (SCA) connections with other nodes.

The following sections discuss these two panes.

Notes about Pane Displays

Following are notes about the display of data in the panes:

• The Availability Manager signals the LOVOTE event when the difference between the cluster's quorum and votes is less than the threshold for the event:

  LOVOTE, 'node' VOTES count is close to or below QUORUM

  
  The default threshold for LOVOTE is 1.

• You can change collection intervals by using the Customize menu on the main Application window. Choose the Customize OpenVMS... option, and then click the Data Collection tab. On the page displayed, you can select data that you want to collect and change the default collection intervals.

Table 3-5 describes the Summary pane data (see Figure 3-18).

Table 3-5 Summary Pane Data

Data	Description
Formed	Date and time the cluster was formed.
Last Trans	Date and time of the most recent cluster state transition.
Votes	Total number of quorum votes being contributed by all cluster members and by the quorum disk.
Expected Votes	Number of votes expected to be contributed by all members of the cluster as determined by the connection manager. This value is based on the maximum EXPECTED_VOTES system parameter and the maximized value of the VOTES system parameter.
Failover Step	Current failover step index. Shows which step in the sequence of failover steps the failover is currently executing.
Members In	Number of cluster members to which the Availability Manager has a connection.
Members Out	Number of cluster members to which the Availability Manager either has no connection or has lost connection.
Quorum	Number of votes required to keep the cluster above quorum.
QD Votes	Number of votes given to the quorum disk. A value of 65535 means there is no quorum disk.
Failover ID	Failover instance identification. Unique ID of a failover sequence that indicates to system managers whether a failover has occurred since the last time they checked.

3.2.7.2 Cluster Members Pane

The Cluster Members pane lists all the nodes in the cluster and provides detailed information about each one. The first level of information in the Cluster Members pane contains cluster member data (see Figure 3-18), which is described in Table 3-6.

Table 3-6 Cluster Member Data

Data	Description
SCS Name	System Communications Services (SCS) name for the node (system parameter SCSNODE).
SCSID	SCS identification for the node (system parameter SCSYSTEMID).
CSID	Cluster system identification.
Votes	Number of votes the member contributes.
Expect	Member's expected votes as set by the EXPECTED_VOTES system parameter.
Quorum	Number of votes that must be present for the cluster to function and permit user activity.
LckDirWt	Lock manager distributed directory weight as determined by the LCKDIRWT system parameter.
Status	Current cluster member status: MEMBER, UNKNOWN, or BRK_NON (break nonmember).
Transition Time	Time cluster member had last transition.

3.2.7.3 System Communications Architecture (SCA) Virtual Circuit (VC) Data

SCA VC data includes information about members' virtual circuits to other members of the cluster. More than one virtual circuit indicates more than one path to the other member.

The data displayed is similar to the information that the Show Cluster utility (SHOW CLUSTER) displays for the CIRCUITS, CONNECTIONS, and COUNTERS classes. However, in Availability Manager Version 1.3 and earlier, SHOW CLUSTER displays show connections and virtual circuits to other OpenVMS nodes only; they do not show connections and virtual circuits to the DIGITAL Storage Architecture (DSA) devices, such as FDDI or DSSI disk controllers. This limitation will be fixed in a future release of the Availability Manager software.

You can display virtual circuit data by double-clicking the SCS name of a node. Figure 3-19 is an example of virtual circuit data on a Cluster Summary page. (Because it is very wide, the illustration splits the screen into two sections; the bottom screen is a continuation of the top screen.)

Figure 3-19 Virtual Circuit Data Page

Table 3-7 describes virtual circuit data. Each line shows either a summary of all system applications (SYSAPs) that use virtual circuit communication or the communication on the connection between a local and a remote SYSAP.

Table 3-7 Virtual Circuit Data

Data	Description
NodeName	SCS name of the remotely connected node.
LPortName	The device name of the local port associated with the circuit.
RPortType	The type of remote port associated with the circuit.
State	The state of the virtual circuit connection.
MsgSent	Rate that messages are sent on the virtual circuit.
MsgRcvd	Rate that messages are received on the virtual circuit.
KB Mapped	Number of kilobytes mapped for block data transfer using the virtual circuit.
BlkDataSent	Number of kilobytes sent on the virtual circuit by this node using send block data transfers.
BlkDataReqd	Number of kilobytes requested on the virtual circuit by this node using request block data transfers.
BlkTransSent	Number of send block data transfers by this node on the virtual circuit.
BlkTransReqd	Number of request block data transfers by this node on the virtual circuit.
DGSent	Number of datagrams sent by this node on the virtual circuit.
DGRcvd	Number of datagrams received from the remote system on the virtual circuit.
CreditWt	Number of times any connection on the virtual circuit had to wait for a send credit.
BDTWt	Number of times any connection on the virtual circuit had to wait for a buffer descriptor.

3.2.7.4 SCS Connections Data

You can display SCS connections data by double-clicking the SCS Connections icon displayed under a virtual circuit node name.

See Figure 3-19 for SCS connections data on a Cluster Summary page. Table 3-8 describes the SCS connections data.

Table 3-8 SCS Connections Data

Data	Description
Local SYSAP	Name of the local system application using the SCS connection.
Remote SYSAP	Name of the remote system application communicated with using the SCS connection.
State	The state of the SCS connection.
MsgSent	Rate that messages are sent to the remote SYSAP using the SCS connection.
MsgRcvd	Rate that messages are received from the remote SYSAP using the SCS connection.
KB Mapped	Number of kilobytes mapped for block data transfer using the SCS connection. Note: This field is available only in raw data format.
BlkDataSent	Number of kilobytes sent on the SCS connection by this node using send block data transfers.
BlkDataReqd	Number of kilobytes the data requested on the SCS connection by this node using request block data transfers.
BlkTransSent	Number of send block data transfers by this node on the SCS connection.
BlkTransReqd	Number of request block data transfers by this node on the SCS connection.
DGSent	Number of datagrams sent by this node on the SCS connection.
DGRcvd	Number of datagrams received from the remote system on the SCS connection.
CreditWt	Number of times the connection had to wait for a send credit.
BDTWt	Number of times the connection had to wait for a buffer descriptor.

3.2.7.5 LAN Virtual Circuit Details Data

You can display LAN virtual circuit details by double-clicking the icon preceding that heading on the Cluster Summary page. The data items displayed depend of the type of virtual circuit. Currently, this feature is available only for LAN virtual circuits.

See Figure 3-19 for a LAN virtual circuit data display. Table 3-9 describes the LAN virtual circuit details data.

Table 3-9 LAN Virtual Circuit Details Data

Data	Description
BufSz	Maximum data buffer size in use by this LAN virtual circuit.
ReXMTRatio	Ratio of retransmitted to transmitted packets during the most recent data collection interval.
ReXMTTimOut (µs)	Retransmission timeout (in microseconds). The amount of time the virtual circuit will wait for acknowledgment of a packet's receipt before retransmitting the packet.
WinSz	Current value of the transmit window (or pipe quota). Maximum number of packets that will be sent before stopping to await an acknowledgment. After a timeout, the transmit window is reset to 1 to decrease congestion and is allowed to increase as acknowledgments are received.
WinSzMax	Maximum transmit window size currently allowed for the virtual circuit.
#Chans	Number of channels 1 available to the virtual circuit.
TimeOpened	Most recent time the virtual circuit was opened. Not implemented in this release.
TimeClosed	Most recent time the virtual circuit was closed. Not implemented in this release.

For more detailed explanations of these data, refer to the NISCA troubleshooting information in the OpenVMS Cluster Systems manual.

3.2.8 OpenVMS Network Interconnect for the System Communication Architecture (NISCA) Pages

The Network Interconnect for the System Communication Architecture (NISCA) is the transport protocol responsible for carrying messages such as disk I/Os and lock messages across Ethernet and FDDI LANs to other nodes in the cluster. More detailed information about the protocol is in the OpenVMS Cluster Systems manual.

The NISCA pages show detailed information about the LAN (Ethernet or FDDI) connection between two nodes. The Availability Manager displays one window for each LAN virtual circuit.

The pages are intended primarily as real-time aids to diagnosing LAN-related problems. The OpenVMS Cluster Systems manual describes the parameters shown in these pages and tells how to diagnose LAN-related cluster problems. The pages provide the same information as the OpenVMS System Dump Analyzer (SDA) command SHOW PORTS/VC=VC_node-name. (VC refers to a virtual circuit; node-name refers to a node in the cluster. The system defines VC-node-name after a SHOW PORTS command is issued from SDA.)

To display NISCA details, double-click the buffer size data item (BufSz) under the LAN Virtual Circuit Details heading on the Cluster Summary page (Figure 3-20).

Figure 3-20 LAN Virtual Circuit Details

The system then displays a Transmit Data page (Figure 3-24) that contains five additional tabs you can select. These pages are described in the following sections.

Notes about the Display

Following are notes about displaying data in this window:

• You cannot sort or filter the data displayed.
• You can change collection intervals.

Channel selection data includes information about the selection of virtual circuit channels. Figure 3-21 is an example of a Channel Selection Data page.

Figure 3-21 Channel Selection Data Page

The following table describes the data displayed:

Data	Description
Buffer Size	Maximum data buffer size for this virtual circuit.
Channel Count	Number of channels available for use by this virtual circuit.
Channel Selections	Number of channel selections performed.
Protocol	NISCA protocol version.
Local Device	Name of the local LAN device that the channel uses to send and receive packets.
Local LAN Address	Address of the local LAN device that performs sends and receives.
Remote Device	Name of the remote LAN device that the channel uses to send and receive packets.
Remote LAN Address	Address of the remote LAN device performing the sends and receives.

3.2.8.2 Virtual Circuit (VC) Closures Data

VC closures data is information about the number of times a virtual circuit has closed for a particular reason. Figure 3-22 is an example of a VC Closures Data page.

Figure 3-22 Virtual Connect (VC) Closures Data Page

The following table describes the displayed data:

Data	Description
SeqMsg TMO	Number of times the VC was closed because of sequenced transmit timeouts.
CC DFQ Empty	Number of times the VC was closed because the channel control data-free queue (DFQ) was empty.
Topology Change	Number of times the VC was closed because PEDRIVER performed a failover from a LAN path with a large packet size to a LAN path with a smaller packet size, necessitating the closing and reopening of the virtual circuit.
NPAGEDYN Low	Number of times the virtual circuit was lost because of a pool allocation failure on the local node.

3.2.8.3 Packets Discarded Data

Packets discarded data is information about the number of times packets were discarded for a particular reason. Figure 3-23 is an example of a Packets Discarded Data page.

Figure 3-23 Packets Discarded Data Page

The following table describes the displayed data:

Data	Description
No Xmt Chan	Number of times there was no transmit channel.
Rcv Short Msg	Number of times an undersized transport message was received.
Ill Seq Msg	Number of times an illegal sequenced message was received.
Bad Checksum	Number of times there was a checksum failure on a received packet.
TR DFQ Empty	Number of times the transmit data-free queue (DFQ) was empty.
TR MFQ Empty	Number of times the transmit message-free queue (MFQ) was empty.
CC MFQ Empty	Number of times the channel control MFQ was empty.
Cache Miss	Number of packets that could not be placed in the virtual circuit's receive cache because the cache was full.

3.2.8.4 Transmit Data

Transmit data is information about data packet transmission. Figure 3-24 is an example of a Transmit Data page.

Figure 3-24 Transmit Data Page

The following table describes the displayed data:

Data	Description
Packets	(Raw) count and rate of packets transmitted through the virtual circuit to the remote node, including both sequenced and unsequenced (channel control) messages and lone acknowledgments.
Unsequenced (DG)	(Raw) count and rate of the number of unsequenced packets transmitted.
Sequenced	(Raw) count and rate of sequenced packets transmitted. Sequenced packets are guaranteed to be delivered.
Lone ACK	(Raw) count and rate of packets sent solely for the purpose of acknowledging receipt of one or more packets.
ReXMT Count	Number of packets retransmitted. Retransmission occurs when the local node does not receive an acknowledgment for a transmitted packet within a predetermined timeout interval.
ReXMT Timeout	Number of retransmission timeouts that have occurred.
ReXMT Ratio	Ratio of current and past retransmission count to the current and past number of sequenced messages sent.
Bytes	(Raw) count and rate of bytes transmitted through the virtual circuit.

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