The SCROLL command scrolls a monitor picture.

Format

SCROLL direction [amount]

Description

The SCROLL command causes the last picture that was displayed using the MONITOR command to be scrolled in the direction specified and then redisplayed.

Parameters

direction

Specifies the direction in which the screen is to be scrolled. Can be one of LEFT , RIGHT , UP , DOWN or HOME .

HOME scrolls the picture so that its top-left corner coincides with the top-left corner of the screen.

amount

Specifies the number of rows/columns by which the screen is scrolled. Amount is ignored if direction is specified as HOME .

Related commands

• MONITOR

Examples

 RTR> MONITOR TPS/INTERVAL=10) (1)
 RTR> SCROLL UP 10  (2)
 RTR> SCROLL HOME  (3)
      

1. Displays the TPS picture. This picture displays each process using RTR on a separate line. If there is insufficient space on the screen to display them all, the SCROLL command can be used to view a different portion of the list of processes.
2. Scrolls the picture up 10 lines. Note that SCROLL automatically redisplays the current picture.
3. Restores the original picture position.

The SET ENVIRONMENT command specifies the node where RTR commands entered from the same RTR> prompt are executed.

Format

SET ENVIRONMENT

Description

The SET ENVIRONMENT command causes RTR commands entered from the same RTR> prompt to be executed on the specified nodes. Entering SET ENVIRONMENT without any qualifiers causes RTR commands entered from the same RTR> prompt to be executed on the local node only.

Qualifiers

/CLUSTER

Specifies that RTR commands entered from the same RTR> prompt are executed on all nodes in the cluster.

/NODE[=node-list]

Specifies that subsequent RTR commands are executed on all nodes specified in node-list . If node-list is omitted, or both the /NODE and /CLUSTER qualifiers are omitted, subsequent commands are executed on only the local node.

Related commands

• SHOW ENVIRONMENT

Examples

See Section 1.4, Remote Commands, for examples of how to use the SET ENVIRONMENT command.

The SET FACILITY command sets various facility-related options.

Format

SET FACILITY facility-name

Description

The SET FACILITY command sets the router load balancing and quorum characteristics of a facility.

Qualifiers

/BROADCAST_MINIMUM_RATE=Bps

/BROADCAST_MINIMUM_RATE=1000

/BROADCAST_MINIMUM_RATE=nnnn specifies the minimum rate (in bytes per second) to which flow control can reduce broadcast traffic on outgoing facility links from the node concerned.

For example, consider a facility has 100 frontends and 99 of them are able to receive data at a rate of 2KB per second, but one frontend has become congested and is not able to receive any. This can result in all the frontends slowing down to the rate that the slowest can accept.

Specifying /BROADCAST_MINIMUM_RATE=2000 on the router ensures that the 99 frontends receive their broadcasts, and that RTR attempts to send the broadcasts to the congested frontend. However, broadcasts for the congested frontend are discarded (if absolutely necessary) rather than slowing down all frontends to the rate that the slowest can accept.

Specifying /BROADCAST_MINIMUM_RATE without a value gives a default 1000 bytes per second; if you do not use the qualifier, the minimum is zero.

/BALANCE

/NOBALANCE

/BALANCE specifies whether router load balancing is to be performed.

The default behavior (/NOBALANCE) is for a frontend to connect to the preferred router. Preferred routers are selected in the order specified in the /ROUTER qualifier of the CREATE FACILITY command. This preference is subject to the Router being available and quorate. See Section 2.7, Router Load Balancing, for more information on load balancing.

/CLUSTER

/NOCLUSTER (D)

Specifies that the command is executed on all the nodes in the cluster.

If neither /NODE nor /CLUSTER is specified, the command is executed on the nodes specified by the latest SET ENVIRONMENT command. If no SET ENVIRONMENT command has been entered, the command is executed only on the node where the command was issued.

Note In environments that do not support clustering, the /CLUSTER qualifier causes the relevant command to be executed on the local node only.

/NODE[=node-list]

/NODE=default-node (D)

Specifies that the command is executed on all nodes specified in node-list . If node-list is omitted, the command is executed only on the node where the command was issued.

/OUTPUT[=filespec]

/OUTPUT=stdout (D)

Specifies that the resulting information is written to the file filespec . If /OUTPUT or filespec is omitted, the standard or default output is used.

/QUORUM_THRESHOLD=n

/QUORUM_THRESHOLD=0

/QUORUM_THRESHOLD=n sets the minimum number of nodes/role combinations that have to be reachable to declare the configuration quorate .

Note A node that combines both backend and router roles is counted twice in determining the threshold. A value of zero implies that the RTR determined threshold (half the number of node/role pairs configured plus one) is used. This is the default value; do not alter it unless you are sure that the unreachable nodes are really down. Before the rest of the nodes are started, this value should be reset to zero, the default setting. The current value of quorum_threshold can be displayed with the SHOW FACILITY /STATE command.

/REPLY_CHECKSUM

/NOREPLY_CHECKSUM (D)

Specifies that the reply consistency check (or Response Matching) feature for replayed messages is enabled. It is a check for reply consistency during a replay of a reply to client message.

RTR can enable, disable and display this feature.

Related commands

• SHOW FACILITY

Examples

 RTR> SET FACILITY FINANCE/QUORUM_THRESHOLD=4
quorum threshold set to 4 (from 0) for facility FINANCE
      

The SET FACILITY command tells RTR to set the quorum threshold to four for facility FINANCE. This command should be used on all the backend and router nodes in the facility.

 RTR> SET FACILITY FINANCE/BALANCE
      

This command tells RTR to use router load balancing.

The SET LINK command sets various link related options.

Format

SET LINK link-name

Description

The SET LINK command sets options for one or more links. The options are link enabled or disabled, link autoisolate, link checksum and link inactivity timeout.

The parameter link-name is the node from which connect attempts are to be honored (or not). Note that disabling the link prevents incoming connections over an established link. It only takes affect when new connect attempts are made. It does not affect the ability to connect to a node whose link has been disabled. The link-name can be wildcarded.

The current state of the link can be displayed with the SHOW LINK/STATUS command. When looking at connection problems, both ends of the link counters should be used with the SHOW LINK/COUNTER command.

Qualifiers

/AUTOISOLATE

/NOAUTOISOLATE (D)

Any RTR node may disconnect a remote node if it finds the remote node is unresponsive or congested. The normal behavior following such action is automatic network link reconnection and recovery.

Node autoisolation allows a node (the isolator) to disconnect a congested or unresponsive remote node (the isolatee) in such a way that when the congested node attempts to reconnect, it receives an instruction to close all its network links and cease connection attempts. A node in this state is termed isolated.

Some applications require that a node suspected of causing congestion (that is, not processing network data quickly enough) is isolated from the rest of the network, so as to cause minimum disruption. The node autoisolation feature meets this requirement.

Remote node autoisolation can be enabled (at the isolator) where it applies to all links using SET NODE/AUTOISOLATE, or for specific links only with the SET LINK/AUTOISOLATE command. An isolated node (isolatee) remains isolated until you perform both of the following actions:

• Enable the link to the isolated node on all nodes that have isolated it, that is set link [isolated-node]/enable
• Exit the isolated state on the isolated node, that is set node/noisolate

Autoisolation is disabled (at the isolator) using the /NOAUTOISOLATE qualifier.

/CHECKSUM

/NOCHECKSUM (D)

/CHECKSUM specifies that checksum calculations for data packets over network links are performed. This qualifier is by default set to /NOCHECKSUM.

This command is useful for diagnosing errors over network links. To see the checksum state, use the SHOW LINK/STATE command.

/ENABLE

/DISABLE

/ENABLE specifies that connect attempts are honored from the node specified by link-name .

This command is used to enable a link in a disabled state. A link can be disabled either as a result of operator action, or automatically if it has been suspected of causing severe congestion. If a link is automatically disabled, an entry is made in the RTR error log.

/DISABLE specifies that connect attempts are no longer honored from the node link-name . Note that disabling the link does not have any immediate effect on an established link. It only takes effect when new connection attempts are made.

/CLUSTER

/NOCLUSTER (D)

Specifies that the command is executed on all the nodes in the cluster.

If neither /NODE nor /CLUSTER is specified, the command is executed on the nodes specified by the latest SET ENVIRONMENT command. If no SET ENVIRONMENT command has been entered, the command is executed only on the node where the command was issued.

Note In environments that do not support clustering, the /CLUSTER qualifier causes the relevant command to be executed on the local node only.

/INACTIVITY_TIMEOUT[=secs]

/INACTIVITY_TIMEOUT=node-default

/INACTIVITY_TIMEOUT[=secs] specifies the maximum elapsed time in seconds before RTR discards a link that is neither receiving traffic nor responding to explicit link state queries. Link failover occurs between the adjustable environmental timer parameters RTR_TIMEOUT_CONNECT , default of 60 seconds, and RTR_TIMEOUT_CONNECT_RELAX , default of 90 seconds, on a network link or remote node. When there is a failure, RTR detects it within the timer parameters stipulated and disconnects and retries the link according to the router preferences for a frontend. If a router fails to respond to the reconnect tries, there will be a time lapse of RTR_TIMEOUT_CONNECT plus RTR_TIMEOUT_CONNECT_RELAX for the link failover to occur.

The new value for secs becomes effective only after a time of about one third of the current value of the link inactivity timeout.

The minimum useful value for secs is three. If a value is not specified, links inherit the current value of the node inactivity timeout. (See SET NODE/INACTIVITY_TIMEOUT.)

You can check the current value of the link inactivity timeout with the command SHOW LINK linkname /COUNTER= ndb_lw_inact .

You should not specify a value of less than five times the time required for a round trip over the link. If you don't know this value, RTR can measure it for you. Make sure that there is no transactional traffic over the link, and monitor the link (with the MONITOR LINK command) between the two nodes whose round trip time you want to measure. After a few minutes, look at the link counters ndb_lw_trips and ndb_lw_trips_ms using the SHOW LINK/COUNTER= ndb_lw_trips* command. Dividing the latter by the former yields the average round trip time in milliseconds.

Note The inactivity timeout is used for all RTR links, but the effect of a timeout and failover depends on what connections the link is supporting. In brief, a link between a router and a backend timing out causes a router or backend failover and quorum re-negotiations. A frontend will search for another router.

/NODE[=node-list]

/NODE=default-node (D)

Specifies that the command is executed on all nodes specified in node-list . If node-list is omitted, the command is executed only on the node where the command was issued.

/OUTPUT[=filespec]

/OUTPUT=stdout (D)

Specifies that the resulting information is written to the file filespec . If /OUTPUT or filespec is omitted, the standard or default output is used.

/SUSPECT

/NOSUSPECT

Obsolete. Available for compatibility reasons only; use /AUTOISOLATE instead.

Related commands

• SET NODE/AUTOISOLATE
• SHOW LINK/STATUS

Examples

 RTR> SET LINK JOEY/ENABLE
      

This command reallows connections from node JOEY.

 RTR> SET LINK JOEY/AUTOISOLATE
      

This command sets the autoisolate attribute on the link to node JOEY.

The SET LOG command specifies where RTR writes its log messages.

Format

SET LOG

Description

The SET LOG command specifies where RTR writes its log messages. You can write log messages to the operator console and to a maximum of four log files. Log files must be periodically purged to avoid difficulties with full disks. Do this by using SET LOG to specify a new file and deleting the old one.

If neither the /OPERATOR nor the /FILE qualifier is specified, logging is suppressed.

Note Log files must always be accessible even if a node fails.

Qualifiers

/CLUSTER

/NOCLUSTER (D)

Specifies that the command is executed on all the nodes in the cluster.

If neither /NODE nor /CLUSTER is specified, the command is executed on the nodes specified by the latest SET ENVIRONMENT command. If no SET ENVIRONMENT command has been entered, the command is executed only on the node where the command was issued.

Note In environments that do not support clustering, the /CLUSTER qualifier causes the relevant command to be executed on the local node only.

/FILE=filespec-list

/NOFILE (D)

Specifies the names of up to four files where the log messages are written. The given file name is appended with .log.

/NODE[=node-list]

/NODE=default-node (D)

Specifies that the command is executed on all nodes specified in node-list . If node-list is omitted, the command is executed only on the node where the command was issued.

/OPERATOR

/NOOPERATOR (D)

Specifies that messages are written to the operator log.

/OUTPUT[=filespec]

/OUTPUT=stdout (D)

Specifies that the resulting information is written to the file filespec . If /OUTPUT or filespec is omitted, the standard or default output is used.

Related commands

• SHOW LOG

Examples

 RTR> SET LOG/FILE=RTRLOG.LOG/OPERATOR
      

This command tells RTR to write log messages to the file RTRLOG.LOG and to the operator log.

 RTR> SET LOG/NOFILE/NOOPERATOR
      

This command suppresses all RTR log messages.

 RTR> SET LOG/FILE="/usr/users/rtruser/daily_logfile"
      

This command tells RTR to write log messages to the file /usr/users/rtruser/daily_logfile.log .

 RTR> SET LOG/FILE=("logfile1.log","logfile2.log")
      

This command tells RTR to write log messages to logfile1.log and logfile2.log .

 RTR> SET LOG/OPERATOR
      

This command tells RTR to write log messages to the system log.

The SET MODE command specifies whether RTR should run in a group mode or the nogroup (system) mode.

Format

SET MODE

Description

The SET MODE command specifies whether RTR runs in group mode or nogroup mode. (Nogroup mode is the same as system mode.)

Production systems use RTR in the default (that is, nogroup or system) mode, whereby all users running in this mode use one common invocation of RTR.

Developers typically have their own invocation of RTR to avoid their RTR actions affecting other developers or the production system. This mode is termed group mode. Group mode allows development or testing of applications by several groups of people on the same system without interference.

Qualifiers

/CLUSTER

/NOCLUSTER (D)

Specifies that the command is executed on all the nodes in the cluster.

If neither /NODE nor /CLUSTER is specified, the command is executed on the nodes specified by the latest SET ENVIRONMENT command. If no SET ENVIRONMENT command has been entered, the command is executed only on the node where the command was issued.

Note In environments that do not support clustering, the /CLUSTER qualifier causes the relevant command to be executed on the local node only.

/GROUP[=user-id

/NOGROUP

/GROUP specifies that RTR be set to GROUP mode for the user who issues the command. The group name defaults to the first eight characters of your current user-id. You may also change to another group by entering a user or group ID. Note that group names are used for naming RTR journal files; do not use a group name containing the string SYSTEM or conflicts may occur.

RTR> set mode/group=develpr

/NOGROUP sets RTR into NOGROUP mode.

/NODE[=node-list]

/NODE=default-node (D)

Specifies that the command is executed on all nodes specified in node-list . If node-list is omitted, the command is executed only on the node where the command was issued.

/OUTPUT[=filespec]

/OUTPUT=stdout (D)

Specifies that the resulting information is written to the file filespec . If /OUTPUT or filespec is omitted, the standard or default output is used.

Related commands

• SHOW MODE

Examples

 RTR> SET MODE/GROUP
      

This command tells RTR to enter GROUP mode.

 RTR> SET MODE/NOGROUP
      

This command tells RTR to enter NOGROUP mode.