The BBL on machine sends an "I'm OK" message to the DBBL every time it performs a sanity check of its machine. This check occurs every "SANITYSCAN * SCANUNIT" seconds, as specified in the RESOURCES section. Similarly, every BBLQUERY
* SCANUNIT
seconds, the DBBL performs a sanity check of all BBLs. If an "I'm OK" message has not been received from machine during the previous "BBLQUERY * SCANUNIT" seconds, the DBBL prints this warning message. Then an explicit sanity check is done over the network. If this check also fails, machine will be considered partitioned.