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Compaq AA-Q88CE-TE User Manual

Page 190

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SET LINK

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-list (D)

Specifies that the command is executed on all nodes specified in

node-list

. If

node-list

is omitted then the command is executed only on the node where the

command was issued.

/OUTPUT[=file-spec]
/OUTPUT=stdout (D)

Specifies that the resulting information is written to the file

file-spec

. If

/OUTPUT

or

file-spec

is omitted then 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

6–114 RTR Command Line Interface