Add basic bond health status reporting (listbonds)

node/Bond.cpp

@@ -730,6 +730,9 @@ void Bond::curateBond(const int64_t now, bool rebuildBond)
 {
 	//fprintf(stderr, "%lu curateBond (rebuildBond=%d), _numBondedPaths=%d\n", ((now - RR->bc->getBondStartTime())), rebuildBond, _numBondedPaths);
 	char pathStr[128];
+
+	uint8_t tmpNumAliveLinks = 0;
+	uint8_t tmpNumTotalLinks = 0;
 	/**
 	 * Update path states
 	 */
@@ -737,6 +740,10 @@ void Bond::curateBond(const int64_t now, bool rebuildBond)
 		if (!_paths[i]) {
 			continue;
 		}
+		tmpNumTotalLinks++;
+		if (_paths[i]->alive(now, true)) {
+			tmpNumAliveLinks++;
+		}
 		bool currEligibility = _paths[i]->eligible(now,_ackSendInterval);
 		//_paths[i]->address().toString(pathStr);
 		//fprintf(stderr, "\n\n%ld path eligibility (for %s, %s):\n", (RR->node->now() - RR->bc->getBondStartTime()), getLink(_paths[i])->ifname().c_str(), pathStr);
@@ -764,6 +771,46 @@ void Bond::curateBond(const int64_t now, bool rebuildBond)
 		}
 		_paths[i]->_lastEligibilityState = currEligibility;
 	}
+	_numAliveLinks = tmpNumAliveLinks;
+	_numTotalLinks = tmpNumTotalLinks;
+
+	/* Determine health status to report to user */
+
+	bool tmpHealthStatus = true;
+
+	if (_bondingPolicy == ZT_BONDING_POLICY_ACTIVE_BACKUP) {
+		if (_numAliveLinks < 2) {
+			// Considered healthy if there is at least one failover link
+			tmpHealthStatus = false;
+		}
+	}
+	if (_bondingPolicy == ZT_BONDING_POLICY_BROADCAST) {
+		if (_numAliveLinks < 1) {
+			// Considerd healthy if we're able to send frames at all
+			tmpHealthStatus = false;
+		}
+	}
+	if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR) {
+		if (_numAliveLinks < _numTotalLinks) {
+			// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
+			tmpHealthStatus = false;
+		}
+	}
+	if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR) {
+		if (_numAliveLinks < _numTotalLinks) {
+			// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
+			tmpHealthStatus = false;
+		}
+	}
+	if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
+		if (_numAliveLinks < _numTotalLinks) {
+			// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
+			tmpHealthStatus = false;
+		}
+	}
+
+	_isHealthy = tmpHealthStatus;
+
 	/**
 	 * Curate the set of paths that are part of the bond proper. Selects a single path
 	 * per logical link according to eligibility and user-specified constraints.
@@ -1509,6 +1556,10 @@ void Bond::setReasonableDefaults(int policy, SharedPtr<Bond> templateBond, bool
 	_lastCheckUserPreferences = 0;
 	_lastBackgroundTaskCheck = 0;
 
+	_isHealthy = false;
+	_numAliveLinks = 0;
+	_numTotalLinks = 0;
+
 	_downDelay = 0;
 	_upDelay = 0;
 	_allowFlowHashing=false;

node/Bond.hpp

@@ -485,6 +485,21 @@ public:
 	 */
 	inline uint8_t getPolicy() { return _bondingPolicy; }
 
+	/**
+	 * @return the health status of the bond
+	 */
+	inline bool isHealthy() { return _isHealthy; }
+
+	/**
+	 * @return the number of links comprising this bond which are considered alive
+	 */
+	inline uint8_t getNumAliveLinks() { return _numAliveLinks; };
+
+	/**
+	 * @return the number of links comprising this bond
+	 */
+	inline uint8_t getNumTotalLinks() { return _numTotalLinks; }
+
 	/**
 	 *
 	 * @param allowFlowHashing
@@ -626,6 +641,10 @@ private:
 	uint16_t _maxAcceptablePacketDelayVariance;
 	uint8_t _minAcceptableAllocation;
 
+	bool _isHealthy;
+	uint8_t _numAliveLinks;
+	uint8_t _numTotalLinks;
+
 	/**
 	 * Default initial punishment inflicted on misbehaving paths. Punishment slowly
 	 * drains linearly. For each eligibility change the remaining punishment is doubled.

node/Node.cpp

@@ -513,6 +513,9 @@ ZT_PeerList *Node::peers() const
 		if (pi->second->bond()) {
 			p->isBonded = pi->second->bond();
 			p->bondingPolicy = pi->second->bond()->getPolicy();
+			p->isHealthy = pi->second->bond()->isHealthy();
+			p->numAliveLinks = pi->second->bond()->getNumAliveLinks();
+			p->numTotalLinks = pi->second->bond()->getNumTotalLinks();
 		}
 	}