[Confluence 6.0] Synchrony: Connections could not be acquired from the underlying database

$ atlas-version

ATLAS Version:    6.2.4
ATLAS Home:       /usr/share/atlassian-plugin-sdk-6.2.4
ATLAS Scripts:    /usr/share/atlassian-plugin-sdk-6.2.4/bin
ATLAS Maven Home: /usr/share/atlassian-plugin-sdk-6.2.4/apache-maven-3.2.1
AMPS Version:     6.2.3
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Executing: /usr/share/atlassian-plugin-sdk-6.2.4/apache-maven-3.2.1/bin/mvn --version -gs /usr/share/atlassian-plugin-sdk-6.2.4/apache-maven-3.2.1/conf/settings.xml
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=256M; support was removed in 8.0
Apache Maven 3.2.1 (ea8b2b07643dbb1b84b6d16e1f08391b666bc1e9; 2014-02-14T09:37:52-08:00)
Maven home: /usr/share/atlassian-plugin-sdk-6.2.4/apache-maven-3.2.1
Java version: 1.8.0_101, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-8-oracle/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "3.13.0-91-generic", arch: "amd64", family: "unix"

atlas-debug -v 6.0.0-m70

[INFO] [talledLocalContainer] 2016-09-07 18:55:05,957 DEBUG [282:StdOutHandler java.lang.UNIXProcess@e684b3d] [plugins.synchrony.bootstrap.DefaultSynchronyProcessManager] processLine Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> z8kflt9j22ywl01p5jqnx|4fb1caf1, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> org.h2.Driver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> z8kflt9j22ywl01p5jqnx|4fb1caf1, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:h2:tcp://localhost:9092//home/dmitry/lucid/main/confluence/target/confluence/home/database/h2db;MVCC=TRUE, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 10800, maxIdleTimeExcessConnections -> 1800, maxPoolSize -> 15, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 3, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
[INFO] [talledLocalContainer] 2016-09-07 18:55:36,112 DEBUG [282:StdOutHandler java.lang.UNIXProcess@e684b3d] [plugins.synchrony.bootstrap.DefaultSynchronyProcessManager] processLine com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@25555dcc -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
[INFO] [talledLocalContainer] 2016-09-07 18:55:36,113 DEBUG [282:StdOutHandler java.lang.UNIXProcess@e684b3d] [plugins.synchrony.bootstrap.DefaultSynchronyProcessManager] processLine org.h2.jdbc.JdbcSQLException: Connection is broken: "unexpected status 16777216" [90067-176]

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[INFO] [talledLocalContainer] 2016-09-07 18:56:06,229 DEBUG [282:StdOutHandler java.lang.UNIXProcess@e684b3d] [plugins.synchrony.bootstrap.DefaultSynchronyProcessManager] processLine Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.