prefix resync

Causes the CNA decision-maker process to reevaluate specified prefixes.

prefix resync { all | 
 
                confirmed | 
 
                asserted | 
 
                selected | 
 
                adequate | 
 
                measured | 
 
                using-policy <name> | 
 
                quiet <qtime> | 
 
                <addr> 
 
              }
 
              {
 
                compute-winner-set | 
 
                clear | 
 
                clear-routes-only | 
 
                reassert-route |
 
                verify-auto-created 
 
              }
 
              [ limit <num> ]
 

• name--name of a decision policy
• qtime--quiet time (number of seconds since last measurement); range: 60 through 86400
• addr--prefix address in CIDR format (a.b.c.d/n)
• num--maximum number of prefixes to re-evaluate; range: 1 through 1000000

Must be in system operations mode with privileged level access.

num--60

The prefix resync command is the configuration (periodic reevaluation of prefixes) form of the command, resync prefix, which results in immediate reevaluation of prefixes.

Use one of the following keywords with either version of the command:

• all--all prefixes
• confirmed--all prefixes that have been asserted by CNA and confirmed as in use by the routers
• asserted--all prefixes that have been asserted (includes those that have been confirmed)
• selected--all prefixes that have been selected as the winning route by CNA (includes those that have been asserted)
• adequate--all prefixes that have a sufficient number of measurements in the CNA database to be considered adequately measured
• measured--all prefixes that have at least one measurement in the database
• using-policy--all prefixes associated with the named decision policy
• quiet--all prefixes for which no measurements have been received for the specified period of time

Or, you can specify an individual prefix by its address in CIDR format (a.b.c.d/n).

You can impose a limit on the number of prefixes that will be evaluated regardless of the size of the set, by setting the limit argument.

The limit argument can be used with both prefix resync, the config form of this command, and resync prefix, the exec form. But its greatest value is with the config form, when it can be used to avoid thrashing (nonstop reassertions of routes) if your interval is small and the set large. In some cases, it could take at least as long as the interval to re-evaluate all of the prefixes in the set, causing the decision-maker process to immediately start a new resync cycle immediately upon completion of the previous evaluation.

You must also choose one of the following actions to be taken by the CNA decision-maker process:

• compute-winner-set--the decision-maker process will recompute the winner-set for the specified set of prefixes and reassert the current winner if it is in the winner set
• clear--the decision-maker process will withdraw any CNA-asserted routes for the specified prefixes; this is the equivalent of you executing the clear prefix command for the specified prefixes
• clear-routes-only--the decision-maker process will withdraw any CNA-asserted routes for the specified prefixes without resetting the counters which CNA uses to keep track of user-traffic test hits; this is the equivalent of you executing the clear prefix command for the specified prefixes with routes-only keyword
• reassert-route--the decision-maker process will reassert the route that was most recently selected as the winning route by the normal prefix evaluation process
• verify-auto-created--the decision-maker process will immediately run a validation check on automatically created prefixes (see auto-create-prefixes verify-frequency)

Use the keyword limit to restrict prefixes that will be re-evaluated to the specified number that have gone the longest time without an evaluation.

The following example forces an immediate recomputation of winner set of the 50 asserted-and-confirmed prefixes that have gone the longest without a decision-maker evaluation:

prefix resync confirmed compute-winner-set limit 50