'Internal error' when domain contr. is not reachable

There is a minor problem when using AD or AD Hybrid Authentication and the domain controller is not reachable. The Gateway login page times out and shows the ‘Internal error’ page.
Maybe there is a way to reduce the timeout when checking the AD connection and let the failover auth source be used?

The log shows:

INFO | jvm 1 | 2015/04/29 19:58:14 | WARN [PageAccessSynchronizer ] [19:58:14,808]: Thread 'qtp2280497-1151' failed to acquire lock to page with id '0', attempted for 1 minute out of allowed 1 minute. The thread that holds the lock has name 'qtp2280497-24'. INFO | jvm 1 | 2015/04/29 19:58:14 | WARN [PageAccessSynchronizer ] [19:58:14,808]: "qtp2280497-24" prio=5 tid=24 state=RUNNABLE INFO | jvm 1 | 2015/04/29 19:58:14 | org.apache.wicket.util.lang.Threads$ThreadDump INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.AbstractPlainSocketImpl.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.PlainSocketImpl.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.SocksSocketImpl.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.Socket.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.Socket.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.Socket.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.net.Socket.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.Connection.createSocket(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.Connection.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapClient.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapClient.getInstance(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtx.connect(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtx.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtxFactory.getUsingURL(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtxFactory.getUsingURLs(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtxFactory.getLdapCtxInstance(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.sun.jndi.ldap.LdapCtxFactory.getInitialContext(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at javax.naming.spi.NamingManager.getInitialContext(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at javax.naming.InitialContext.getDefaultInitCtx(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at javax.naming.InitialContext.init(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at javax.naming.ldap.InitialLdapContext.<init>(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.impl.LDAPHelper.openContext(LDAPHelper.java:190) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.impl.LDAPHelper.isUserValid(LDAPHelper.java:215) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.impl.ADtoDBHybridAuthenticator.authenticateAD(ADtoDBHybridAuthenticator.java:114) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.impl.SSOHelper.authenticate(SSOHelper.java:38) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.impl.ADtoDBHybridAuthenticator.authenticate(ADtoDBHybridAuthenticator.java:93) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.authentication.UserSourceWrapper.authenticate(UserSourceWrapper.java:181) INFO | jvm 1 | 2015/04/29 19:58:14 | at com.inductiveautomation.ignition.gateway.web.pages.SignIn$SignInForm.onSubmit(SignIn.java:108) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form$9.component(Form.java:1248) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form$9.component(Form.java:1242) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.util.visit.Visits.visitPostOrderHelper(Visits.java:274) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.util.visit.Visits.visitPostOrder(Visits.java:245) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form.delegateSubmit(Form.java:1241) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form.process(Form.java:923) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.StatelessForm.process(StatelessForm.java:87) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form.onFormSubmitted(Form.java:769) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.markup.html.form.Form.onFormSubmitted(Form.java:702) INFO | jvm 1 | 2015/04/29 19:58:14 | at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) INFO | jvm 1 | 2015/04/29 19:58:14 | at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.lang.reflect.Method.invoke(Unknown Source) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.RequestListenerInterface.internalInvoke(RequestListenerInterface.java:258) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.RequestListenerInterface.invoke(RequestListenerInterface.java:216) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.invokeListener(ListenerInterfaceRequestHandler.java:240) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.respond(ListenerInterfaceRequestHandler.java:226) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:814) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:253) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:210) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:281) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:188) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:245) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.Server.handle(Server.java:497) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:610) INFO | jvm 1 | 2015/04/29 19:58:14 | at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:539) INFO | jvm 1 | 2015/04/29 19:58:14 | at java.lang.Thread.run(Unknown Source)