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configure Bigtable and gRPC logging

I would like to configure logging from Google Cloud Bigtable (gRPC) like the other modules of my application
Logs with SLF4J/log4j with properties configured to dismiss INFO logs from spark
2017-01-11 10:44:08 INFO algoServingLauncherTest$:12 - Starting algo Serving...
2017-01-11 10:44:09 INFO MongoDBAlgorithm$:12 - Retrieving all algorithms from mongodb://mongo:27017/mycompany/algorithms...
2017-01-11 10:44:09 INFO MongoDBAlgorithmHandler$:12 - Algorithms retrieval succeeded (1 algorithms)
2017-01-11 10:44:09 INFO MongoDBPredictor$:12 - Retrieving all predictors from mongodb://mongo:27017/mycompany/predictors...
2017-01-11 10:44:09 INFO MongoDBPredictorHandler$:12 - Predictors retrieval succeeded (13 predictors)
logs from Bigtable gRPC
Jan 11, 2017 10:44:23 AM com.google.bigtable.repackaged.io.grpc.internal.ManagedChannelImpl <init>
INFO: [ManagedChannelImpl#1cf6d1be] Created with target directaddress:///bigtable.googleapis.com/[omitted]:443
Jan 11, 2017 10:44:23 AM com.google.bigtable.repackaged.io.grpc.internal.ManagedChannelImpl <init>
INFO: [ManagedChannelImpl#4b29d1d2] Created with target directaddress:///bigtable.googleapis.com/[omitted]:443
Jan 11, 2017 10:44:23 AM com.google.bigtable.repackaged.io.grpc.internal.ManagedChannelImpl <init>
INFO: [ManagedChannelImpl#7f485fda] Created with target directaddress:///bigtable.googleapis.com/[omitted]:443
I would like to force logging to use SLF4J/Log4j.
What should I do ?
Thanks for your help

Unfortunately there isn't an existing direct SLF4J integration in grpc; grpc currently uses java.util.logging which has some complications.
You may want to read the open GitHub issue which discusses this in a lot more detail, and in particular this comment suggests that you may have some success with SLF4JBridgeHandler.

Connecting Java client to Hazelcast-Kubernetes fails

I'm running a kubernetes cluster in which I am deploying a "cloud native hazelcast" following the instructions on the kubernetes-hazelcast github page. Once I have a number of hazelcast instances running, I try to connect a java client to one of the instances but for some reason the connection fails.
Some background
Using a kubernetes external endpoint I can connect to hazelcast from outside the kubernetes cluster. When I do a REST call with curl kubernetes-master:32469/hazelcast/rest/cluster, I get a correct response from hazelcast with it's cluster information. So I know my endpoint works.
The hazelcast-kubernetes deployment uses the hazelcast-kubernetes-bootstrapper which allows some configuration by setting environment variables with the replication controller, but I'm using all defaults. So my group and password are "someGroup" and "someSecret".
The java client
My Java client code is really straightforward:
ClientConfig clientConfig = new ClientConfig();
clientConfig.getNetworkConfig().setConnectionAttemptLimit(0);
clientConfig.getNetworkConfig().setConnectionTimeout(10000);
clientConfig.getNetworkConfig().setConnectionAttemptPeriod(2000);
clientConfig.getNetworkConfig().addAddress("kubernetes-master:32469");
clientConfig.getGroupConfig().setName("someGroup");
clientConfig.getGroupConfig().setPassword("someSecret")
HazelcastInstance client = HazelcastClient.newHazelcastClient(clientConfig);
When start my client this is the log output of the hazelcast container
2016-07-05 12:54:38.143 INFO 5 --- [thread-Acceptor] com.hazelcast.nio.tcp.SocketAcceptor : [172.16.15.4]:5701 [someGroup] [3.5.2] Accepting socket connection from /172.16.29.0:54333
2016-07-05 12:54:38.143 INFO 5 --- [ cached4] c.h.nio.tcp.TcpIpConnectionManager : [172.16.15.4]:5701 [someGroup] [3.5.2] Established socket connection between /172.16.15.4:5701
2016-07-05 12:54:38.157 INFO 5 --- [.IO.thread-in-1] c.h.nio.tcp.SocketClientMessageReader : [172.16.15.4]:5701 [someGroup] [3.5.2] Unknown client type: <
And the console output of the client
jul 05, 2016 2:54:37 PM com.hazelcast.core.LifecycleService
INFO: HazelcastClient[hz.client_0_someGroup][3.6.2] is STARTING
jul 05, 2016 2:54:38 PM com.hazelcast.core.LifecycleService
INFO: HazelcastClient[hz.client_0_someGroup][3.6.2] is STARTED
jul 05, 2016 2:54:48 PM com.hazelcast.client.spi.impl.ClusterListenerSupport
WARNING: Unable to get alive cluster connection, try in 0 ms later, attempt 1 of 2147483647.
jul 05, 2016 2:54:58 PM com.hazelcast.client.spi.impl.ClusterListenerSupport
WARNING: Unable to get alive cluster connection, try in 0 ms later, attempt 2 of 2147483647.
jul 05, 2016 2:55:08 PM com.hazelcast.client.spi.impl.ClusterListenerSupport
etc...
The client just keeps trying to connect but no connection is ever established.
What am I missing?
So why won't my client connect to the hazelcast instance? Is it some configuration part I'm missing?

Not sure about the official kubernetes support, however Hazelcast has a kubernetes discovery plugin (based on the new discovery spi) that works on both, client and nodes: https://github.com/noctarius/hazelcast-kubernetes-discovery

Looking at the console logs, you have different Hazelcast versions between Node and Client? Can you either update both to be 3.6.4 i.e., the latest or just change the cluster to be 3.6.2 to match with client. 3.6.x has many configuration changes and many bug fixes as well.

SPNEGO Authentication Failing

I have setup kerberos + OpenLDAP authentication for my Apache 2.4 CentOS 7 machine fine. I'm now trying to setup SSO using Kerberos + OpenLDAP for Tomcat 7. For this I've selected SPNEGO. I believe I have all of the LDAP and Kerberos settings working as needed.
Now when browsing to the webapp that has SPNEGO Authentication enabled I'm getting a 401, this is because my user agent isn't sending a WWW-Negotation header. I was expecting this as I haven't got to this point yet.
My question is specific to logging in. In Apache 2.4 I have setup SSO and if no key is present it uses basic authentication and works perfectly, as expected it grants me a TGT after providing credentials and is valid for the entire session.
I'd like to have Tomcat 7 present me with a login prompt on fail such as the 401 error message I'm getting now.
Additionally, I've also setup AJP. Just for testing, I thought I'd try to AJP from Apache to Tomcat with SSO enabled. While watching my kerberos logs, it is infact authenticating when I view the webapp but am still presented with a 401.
tldr;
How can I make Tomcat 7 prompt for a username and password if needed? And is there a way using AJP to stay authenticated from Apache to a webapp over the AJP tunnel?
The following is a snippet of my Tomcat 7 logs, please let me know what other information is needed.
Apr 28, 2016 12:58:08 AM org.apache.catalina.authenticator.AuthenticatorBase invoke
FINE: Security checking request GET /helloworld/
Apr 28, 2016 12:58:08 AM org.apache.catalina.realm.RealmBase findSecurityConstraints
FINE: Checking constraint 'SecurityConstraint[all]' against GET /index.jsp --> true
Apr 28, 2016 12:58:08 AM org.apache.catalina.realm.RealmBase findSecurityConstraints
FINE: Checking constraint 'SecurityConstraint[all]' against GET /index.jsp --> true
Apr 28, 2016 12:58:08 AM org.apache.catalina.authenticator.AuthenticatorBase invoke
FINE: Calling hasUserDataPermission()
Apr 28, 2016 12:58:08 AM org.apache.catalina.realm.RealmBase hasUserDataPermission
FINE: User data constraint has no restrictions
Apr 28, 2016 12:58:08 AM org.apache.catalina.authenticator.AuthenticatorBase invoke
FINE: Calling authenticate()
Apr 28, 2016 12:58:08 AM org.apache.catalina.authenticator.SpnegoAuthenticator authenticate
FINE: No authorization header sent by client
Apr 28, 2016 12:58:08 AM org.apache.catalina.authenticator.AuthenticatorBase invoke
FINE: Failed authenticate() test

Spring JPA unknown error but application works as expected

I'm using Spring 4.0, tomcat 8, spring-data-jpa 1.7.0.RELEASE, hibernate 4.1, mysql 5.6.21 Homebrew. I'm new in java, just moved form C++ background. I assume there must be some resource leaking. I have to close or free something before I exist the app. But no idea what to do. Please advise me!
Every time I restart I got following error:-
Nov 20, 2014 2:01:01 PM org.apache.catalina.loader.WebappClassLoaderBase
clearReferencesThreads
WARNING: The web application [MyJap] appears to have started a thread named [MySQL
Statement Cancellation Timer] but has failed to stop it. This is very likely to create a
memory leak. Stack trace of thread:
java.lang.Object.wait(Native Method)
java.lang.Object.wait(Object.java:502)
java.util.TimerThread.mainLoop(Timer.java:526)
java.util.TimerThread.run(Timer.java:505)
Nov 20, 2014 2:01:01 PM org.apache.coyote.AbstractProtocol start

Disable Tomcat JAAS?

I have an active/passive nodes with Tomcat using heartbeat. When I shutdown the active node, Tomcat on passive node starts. This is a piece of the starting trace:
INFO: Initializing Coyote HTTP/1.1 on http-8080 May 22, 2014
7:37:43 PM org.apache.catalina.startup.Catalina load INFO:
Initialization processed in 366 ms May 22, 2014 7:37:43 PM
org.apache.catalina.realm.JAASRealm setContainer INFO: Set JAAS
app name VentusProxy May 22, 2014 7:37:59 PM
org.apache.catalina.mbeans.JmxRemoteLifecycleListener createServer
It takes 15 seconds to initialize JAAS, that means 15 seconds more without service.
I don't use JAAS at all in my application, so I'd like to disable it or, at least, try to reduce this 15 seconds.
Can anybody tell me if this is possible and how?