JGroups Protocol VERIFY SUSPECT

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External

Internal

Overview

VERIFY_SUSPECT is a protocol that checks a suspected member.

Suspect Verification

VERIFY_SUSPECT verifies that a suspected member is really dead by pinging that member once again. If the member responds, it drops the SUSPECT message. Tries to minimize false suspicions.

The protocol works as follows: it catches SUSPECT events traveling up the stack. Verifies that the suspected member is really dead. If yes, passes SUSPECT event up the stack, otherwise discards it.

VERIFY_SUSPECT must be placed somewhere above the failure detection layer and below the GMS layer (receiver of the SUSPECT event). Note that SUSPECT events may be reordered by this protocol.

Configuration

   <VERIFY_SUSPECT timeout="1500"/>