HP OpenVMS Systems Documentation

HP OpenVMS System Management Utilities Reference Manual

This command sets up port LTA22: as an application port to be associated with the port named LN02 on the terminal server named TS33EW. This command associates port LTA22: with a specific printer on the server. In the next example, the SET PORT command associates a port with a set of printers (designated by the service name PRINTER) on a terminal server.

LATCP> SET PORT LTA19: /APPLICATION /NODE=TLAT1 /SERVICE=PRINTER /QUEUED
      

This command shows how to associate a local logical port with a service (several printers) on a terminal server. The command associates the application port LTA19: with the service PRINTER on terminal server TLAT1. The service PRINTER can be associated with one or more ports on TLAT1. The /QUEUED qualifier specifies that the server offering the service PRINTER can queue the remote connection request if all ports offering the service are in use. Refer to the description of print operations in the HP OpenVMS System Manager's Manual for information about setting up print queues.

LATCP> SET PORT LTA21: /DEDICATED /SERVICE=GRAPHICS
      

This command specifies that the application port LTA21: on the local service node offers the service GRAPHICS to users on terminal servers or on nodes that support outgoing connections. GRAPHICS is a particular utility or application program.

LATCP> SET PORT MAIL_PORT /SERVICE=MAIL/NODE=RMNODE
      

This command associates the port whose logical name is MAIL_PORT with the dedicated service MAIL on remote node RMNODE. The port logically named MAIL_PORT was created with the CREATE PORT command (see Example 3 in the discussion of the CREATE PORT command). The logical name could also have been created with the DCL command ASSIGN or DEFINE. On node RMNODE, a port must be dedicated to the service MAIL by using the SET PORT port-name /DEDICATED/SERVICE=MAIL command.

$ LCP :== $LATCP
$ LCP CREATE SERVICE/LIMITED ONLY_ONE
$ (U>(LCP CREATE PORT/LIMITED LTA1234:)
$ (U>(LCP SET PORT LTA1234: /SERVICE=ONLY_ONE)
      

This series of commands, which includes the SET PORT command, creates a limited service that allows only one user to log in to the system through that service. When a user connects to service ONLY_ONE by responding to the terminal server prompt (Local>), the user is assigned port LTA1234 and then prompted for the user name. Any user who attempts to connect to the same service while LTA1234 has a user logged in receives the "service in use" message.

Dynamically changes the characteristics of a locally offered service. You must have OPER privilege to use this command.

Format

SET SERVICE [service-name]

Parameter

service-name

Specifies the service whose characteristics are to be modified. If a service name is omitted, the default service name is the name of the local node you defined by using the SET NODE command.

Qualifiers

/APPLICATION

Sets up the service as an application service. An application service offers a specific application on the service node rather than all of the resources on the service node. Define a dedicated port for the service by using the CREATE PORT and SET PORT commands.

/CONNECTIONS

/NOCONNECTIONS

Specifies whether a service offered by an OpenVMS system accepts incoming connections. If you use the /NOCONNECTIONS qualifier to disable incoming connections, users cannot connect to that service and receive instead the error message "service is disabled."

By default, a service accepts incoming connections (/CONNECTIONS).

/IDENTIFICATION[="identification-string"]

Describes and identifies a service. Service nodes include the identification string in service announcements. A service node announces its services at regular intervals established with the SET NODE command. Entering the LATCP command SHOW NODE or the DECserver command SHOW NODE generates a display that includes this identification string.

By default, the identification string is the translation of SYS$ANNOUNCE. A service node announces its services at regular intervals established with the SET NODE command.

You cannot specify more than 64 ASCII characters in an identification string (a SYS$ANNOUNCE longer than that will be truncated to the first 64 characters). Enclose the string in quotation marks (" ").

/LIMITED

Specifies that the service is a limited service, using devices assigned the limited characteristic and associated with (mapped to) this limited service. This qualifier is used in conjunction with the SET PORT /LIMITED command (see Example 2).

/LOG

/NOLOG (default)

Specifies whether or not LATCP displays a message confirming that the command was executed. If you do not specify the /LOG or /NOLOG qualifier, the default is that no message will be displayed.

/QUEUED

/NOQUEUED

Specifies whether a locally offered limited (/LIMITED) or application (/DEDICATED) service is allowed to have queued connections when all ports are busy (the default). If you specify /NOQUEUED, incoming connections will be rejected if all ports are busy.

/STATIC_RATING=rating

/NOSTATIC_RATING

Enables or disables dynamic service ratings. A dynamic service rating means that a LAT algorithm calculates the availability of a service dynamically, based on the overall level of activity of the node that offers the service and the amount of memory. When a terminal server or node requests a connection to a service that is offered on two or more service nodes, the requesting node selects the service node with the highest (most favorable) service rating. This selection process is called load balancing.

The dynamic service rating, which is the default, is usually adequate for efficient load balancing on the LAT network. However, when necessary, you can use the /STATIC_RATING qualifier to disable dynamic service ratings so that you can specify a static (fixed) rating. That static rating value does not change until the dynamic service rating is reenabled.

Use the static rating to direct users away from or toward your node temporarily. Static ratings range from 0 to 255. Specify a low value to make the local service node less likely to be used; specify a high value to make the local service node more likely to be used.

If you do not specify either the /STATIC_RATING or /NOSTATIC_RATING qualifier, the default is that the LAT software uses the dynamic service rating.

Limited and application services do not rely exclusively on the dynamically calculated service rating. Instead, they use a portion of the dynamic rating based on how many ports are available for the service. For example, if a limited service has 50 percent of its ports available, the dynamic service rating will be scaled, halved, and then added to 105. When ports are available, the rating will always be above the value 105.

When all ports for a limited or application service are in use, the rating will be based on the scaled dynamic rating and the number of free queue slots on the local node. The rating will always be less then 90.

This rating procedure for limited and application services follows the terminal server rating algorithm for services and available ports that the service offers, while at the same time taking into account the availability of the node (which is the factor used to calculate the dynamic rating).

If your system is licensed for a specific number of units (where only a fixed number of users can log in to the system regardless of how the login limit is set), then all dynamic ratings become 0 when all OpenVMS license units have been consumed. (This forces all node service ratings to the lowest possible value when logins are not possible because all OpenVMS license units have been consumed.)

Note that the LAT software transmits a service announcement message when a user logs in to or out of the system. This allows the system to more quickly provide information about service rating changes that result from a login or logout operation.

Description

The SET SERVICE command dynamically changes the characteristics of a service that you created previously (by interactively entering the CREATE SERVICE command or by running a program that created services).

Examples

LATCP> SET SERVICE SALES /IDENT="SALES FORCE TIMESHARING SERVICES"
      

This command specifies a new identification string, "SALES FORCE TIMESHARING SERVICES", for the service SALES. This string is announced with the service SALES in the multicast messages sent by a service node.

$ LCP :== $LATCP
$ LCP SET SERVICE/LIMITED ONLY_ONE
$ LCP CREATE PORT/LIMITED LTA1234:
$ LCP SET PORT LTA1234: /SERVICE=ONLY_ONE
      

This series of commands changes an existing service to a limited service that allows only one user to log in to the system through that service. When a user connects to service ONLY_ONE by responding to the terminal server prompt (Local>), the user is assigned port LTA1234 and then prompted for the user name. Any user who attempts to connect to the same service while LTA1234 has a user logged in receives the "service in use" message.

Displays the status and LAT characteristics of links on the local node.

Format

SHOW LINK [link-name]

Parameter

link-name

Specifies the name for a LAT data link. A link name can have up to 16 ASCII characters.

If you do not specify a link name, LATCP displays information about all links currently defined for the node.

Qualifiers

/BRIEF

Displays the device name and state of the link. This is the default display.

/COUNTERS

Displays the device counters kept for the link. The numbers displayed represent the values recorded since the last time the counters were reset (when the node first started or when the ZERO COUNTERS command was used).

Do not use the /BRIEF or /FULL qualifier with this qualifier.

The following table lists and describes counters common to both CSMA/CD (carrier sense, multiple access with collision detect) and FDDI (Fiber Distributed Data Interface) links:

Counter	Description
Messages received	The total number of messages received over the link.
Multicast messages received	The total number of multicast messages received over the link.
Bytes received	The total number of bytes of information received over the link.
Multicast bytes received	The total number of multicast bytes received over the link.
System buffer unavailable	The total number of times no system buffer was available for an incoming frame.
Unrecognized destination	The total number of times a frame was discarded because there was no portal with the protocol enabled. This count includes frames received for the physical address only.
Messages sent	The total number of messages sent over the link.
Multicast messages sent	The total number of multicast messages sent over the link.
Bytes sent	The total number of bytes of information sent over the link.
Multicast bytes sent	The total number of bytes of multicast messages sent over the link.
User buffer unavailable	The total number of times no user buffer was available for an incoming frame that passed all filtering.
Data overrun	The total number of bytes lost on the link's device because the local node's input buffers were full. A nonzero value can indicate noisy lines, a bad device, a busy or poorly tuned system (not enough resources allocated), or a hardware problem with another device on the LAN connection.

The following table lists and describes receive errors common to both CSMA/CD and FDDI links. These errors, which are included in the display generated by the SHOW LINK/COUNTERS command, are represented by flags that indicate the error has occurred.

Flag	Description
Block check error	CRC error in packets received.
Framing error	Received frames ended incorrectly.
Frame too long	Frames received longer than length limits.
Frame status error	CRC error on ring noticed by local FDDI station (FDDI only).
Frame length error	Frame length too short (FDDI only).

The following table lists and describes transmit errors common to both CSMA/CD and FDDI links. These errors, which are included in the display generated by the SHOW LINK/COUNTERS command, are represented by flags that indicate the error has occurred.

Flag	Description
Excessive collisions	Frames failed to transmit because the collision limit of 16 was reached (CSMA/CD only).
Carrier check failures	Indicates transceiver problem or short circuit in cable.
Short circuit	Short circuit in cable.
Open circuit	Open circuit in cable.
Frame too long	Frames too long. Indicates a transmission problem in one of the portals using the link.
Remote failure to defer	A remote station failed to defer frames transmission. Could indicate a misconfigured network.
Transmit underrun	Transmission of a frame was too slow. Indicates a hardware controller error.
Transmit failure	Frames failed to transmit.

The following table lists and describes link counters specific to CSMA/CD only:

Counter	Description
Transmit CDC failure	The total number of carrier detect check errors, that is, the number of times the local node failed to detect that another Ethernet station was already transmitting when the local node began transmitting.
Messages transmitted:	Single collision---The total number of times a frame was successfully transmitted on the second attempt after a normal collision on the first attempt. Multiple collision---The total number of times a frame was successfully transmitted on the third or later attempt after normal collisions on previous attempts. Initially deferred---The total number of times a frame transmission was deferred on its first attempt. This counter is used to measure Ethernet contention with no collisions.

The following table lists and describes link counters specific to FDDI only:

Counter	Description
Ring initializations initiated	The total number of times a ring reinitialization was initiated by the link.
Ring initializations received	The total number of times a ring reinitialization was initiated by some other link.
Directed beacons received	The number of times the link detected the directed beacon process. Each invocation of the directed beacon process is counted only once.
Connections completed	The number of times the station successfully connected to the concentrator.
Duplicate tokens detected	The number of times a duplicate token was detected on the link.
Ring purge errors	The number of times the ring purger received a token while still in the ring purge state.
LCT rejects	Link Confidence Test rejects. Indicates a problem with communication between station and concentrator.
Elasticity buffer errors	Elasticity buffer function errors. Indicates a station on the ring with a transmit clock out of tolerance.
MAC error count	The number of times the Media Access Control (MAC) changed the E indicator in a frame from R to S.
Traces initiated	The number of times the PC-trace process was initiated by the link.
Traces received	The number of times the link was requested to perform the PC-trace process.
Ring beacons initiated	The number of times the ring beacon process was initiated by the link.
Link errors	The number of times the Link Error Monitor (LEM) detected an error in a received message. Slow counts are normal.
Duplicate address test failures	The number of times the link address was a duplicate.
FCI strip errors	The number of times a Frame Content Independent Strip operation was terminated by receipt of a token.
LEM rejects	The number of times excessive LEM errors were encountered.
MAC frame count	The total number of frames (other than tokens) seen by the link.
MAC lost count	The total number of times a frame (other than a token) was improperly terminated.

/FULL

Displays the device name, state, and datalink address of the link and indicates whether the DECnet address is enabled.

Description

Displays information about the specified link or all links if you do not specify a link. Depending on the qualifier you use with the SHOW LINK command, you can display a link's device name, state, LAT datalink address, DECnet address, or counters.

Examples

LATCP> SHOW LINK/FULL NETWORK_A
      

This command produces the following display of information about link NETWORK_A:

Link Name: NETWORK_A Datalink Address: 08-00-2B-10-12-E3 Device Name: _ESA7: DECnet Address: Disabled Link State: On

The display in this example gives the device name of link NETWORK_A and the device's hardware address. The link is in the On state.

LATCP> SHOW LINK LINK_A/COUNTERS
      

This command produces the following display of counters for link LINK_A:

Link Name: LINK_A Device Name: _ETA6: Seconds Since Zeroed: 65535 Messages Received: 18582254 Messages Sent: 3550507 Multicast Msgs Received: 15096805 Multicast Msgs Sent: 413178 Bytes Received: 1994694325 Bytes Sent: 290838585 Multicast Bytes Received: 1528077909 Multicast Bytes Sent: 32637472 System Buffer Unavailable: 8724 User Buffer Unavailable: 6269 Unrecognized Destination: 0 Data Overrun: 0 Receive Errors - Transmit Errors - Block Check Error: No Excessive Collisions: No Framing Error: No Carrier Check Failure: No Frame Too Long: No Short Circuit: No Frame Status Error: No Open Circuit: No Frame Length Error: Yes Frame Too Long: No Remote Failure To Defer: No Transmit Underrun: No Transmit Failure: No CSMACD Specific Counters ------------------------ Transmit CDC Failure: 0 Messages Transmitted - Single Collision: 43731 Multiple Collisions: 73252 Initially Deferred: 164508