Reserve behavior of a network tiebreaker

When a node reserves a tiebreaker, the tiebreaker is no longer available and cannot be reserved by any other node. This approach is not feasible for a network tiebreaker. Therefore, the reserve behavior of a network tiebreaker is different in the following way.

After an unsuccessful reservation attempt, no other reservation is possible until the node joined the cluster again. A file is written to /var/ct/, which indicates that a reservation failed. If this file is present, a reserve command for a tiebreaker always fails. An extra process is forked, which watches quorum and removes the block file if the node joined the domain again.

The following sample file was created by the network tiebreaker as the result of a failing tie breaker reserve operation to the external IP instance 123.456.789.1. It contains the time stamp of the failed reserve operation.

# cat /var/ct/samtb_net_blockreserve_123.456.789.1
Mo Jul 4 08:38:40 CEST 2005