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In UserGroupInformation the method reloginfromkeytab not working by zookeeper login class

i am able to use hbasetemplate (spring) to connect hbase thru zookeeper with keytab, but TGT is only good for 10 hours, so using jaas to enable zookeeper login to get new TGT before old one expires, we can get the new TGT, but not able to access hbase by the new TGT, besides, this client is running on window with jdk 1.8.
is apache.zoopkeeper.login the correct way to relogin with new TGT? if so, what am I missing? if not the right way, can we get the option to resolve this issue? greatly appreciated!

is you issue resolved? i think first it needs to be check whether the flag returned session states the ticket to be renewable or not?
Regards
Mukesh

TypeError: g.getResponseHeader is undefined

I have this code:
Connector conn = FrameworkUtil.getConnector(context, ALFRESCO_ENDPOINT_ID);
ConnectorContext c = new ConnectorContext(HttpMethod.POST);
c.setContentType("application/json");
Response res = conn.call("/slingshot/profile/userprofile", c,
new ByteArrayInputStream(buf.toString().getBytes()));
That makes a POST to the link: POST http://localhost:8080/share/service/components/profile/userprofile
But, I got the error:
TypeError: g.getResponseHeader is undefined
...unction(g){var b=g.argument.config;var
f=g.getResponseHeader["Content-Type"]||g....
In a search on the Internet, I saw that this can be a problem that is solved adding Content-Type with CORS.
Something like:
.header("Access-Control-Allow-Headers", "x-requested-with,Content-Type");
How can I do this in my code? With Connector or ConnectorContext I don't find a way to set the header...
Or if this is not the way to solve this, how can I solve this error?

I think you might have a few things configured incorrectly here, or you might be misunderstanding a few things. If you're making a remote connection to the ALFRESCO_ENDPOINT_ID then this typically means that you're trying to connect to the Alfresco Repository - and based on where you say you're trying to make the call from it would appear that this is in a Java-backed WebScript running within the Share application - is this correct?
If so, the URL that should be requested would actually be:
http://localhost:8080/alfresco/service/slingshot/profile/userprofile
Which would be equivalent to calling the following:
http://localhost:8080/share/proxy/alfresco/slingshot/profile/userprofile
(the second URL automatically proxies to the Alfresco enpoint).
If you have both the Alfresco Repository and Share running in the same server (which the use of the port 8080 implies you do) then you shouldn't be hitting CORS issues - unless you're trying to go from localhost to some remote location where the Alfresco Repository is running.
Share/Surf should be taking care of all of this for you - perhaps you can provide a bit more context on exactly what it is you're trying to do,
where the code is running (e.g. WebScript, Share, etc) and where you're trying to connect to?
This might help in best advising how to solve your main problem.

Get Accumulo instance name

I want to use GeoMesa (GIS extension of Accumulo) and virtualized it using Docker just like this repo. Now I want to connect to the Accumulo instance using Java using:
Instance i = new ZooKeeperInstance("docker_instance",zkIP:port);
Connector conn = i.getConnector(user, new PasswordToken(password));
The connetion does not get established and hangs (just like in this question). I can connect to the ZooKeeper instance using using
./zkCli.sh -server ip:port
So i guess the instance_name is wrong. I used the one noted in the repo linked first. However I don't know where how to check the instance_name needed.
To make my problem reproducable I did setup a digital ocean server with all necessary dependencies and accumulo. I tested that the connection to zookeeper is possible using zkCli and checked the credentials using accumulo shell on the server.
Instance i = new ZooKeeperInstance("DIGITAL_OCEAN","46.101.199.216:2181");
// WARN org.apache.accumulo.core.client.ClientConfiguration - Found no client.conf in default paths. Using default client configuration values.
System.out.println("This is reached");
Connector conn = i.getConnector("root", new PasswordToken("mypassw"));
System.out.println("This is not reached");

As a troubleshooting step, you may be able to extract the instance name by using HdfsZooInstance.getInstance().getInstanceName() or by connecting directly to ZooKeeper and listing the instance names with ls /accumulo/instances/

There are multiple easy ways to get the instance_name: Ether just look to the top of the accumulo status page as elserj noted in the comments or use zkCli to connect to Zookeeper and use ls /accumulo/instances / as Christopher answered.
However I could not manage to connect to accumulo using the ordinary Java Connector. Nevertheless I managed to connect to Accumulo using the Proxy-Settings which is a valid solution for me, even that I still would have liked to find the problem.

Error connecting to Oracle database using JDBC [duplicate]

I am new to Oracle, and am trying to run a simple example code with Java, but am getting this error when executing the code.. I am able to start up the listener via CMD and am also able to run SQL Plus. Can anyone give me a hand and tell me what I might be doing wrong?
Update:
I am using JDBC.
Database is local, and I actually had it working but it stopped working just today. I'm not really sure why though. Would you mind giving me some procedures to follow by since I don't know much.

Either:
The database isn't running
You got the URL wrong
There is a firewall in the way.
(This strange error message is produced by Oracle's JDBC driver when it can't connect to the database server. 'Network adapter' appears to refer to some component of their code, which isn't very useful. Real network adapters (NICs) don't establish connections at all: TCP protocol stacks do that. It would have been a lot more useful if they had just let the original ConnectException be thrown, or at least used its error message and let it appear in the stack trace.)

I had the same problem, and this is how I fixed it.
I was using the wrong port for my connection.
private final String DB_URL = "jdbc:oracle:thin:#localhost:1521:orcll"; // 1521 my wrong port
go to your localhost
(my localhost address) : https://localhost:1158/em
login
user name
password
connect as --> normal
Below 'General' click on LISTENER_localhost
look at you port number
Net Address (ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1522))
Connect to port 1522
Edit you connection
change port 1521 to 1522.
done

Another thing you might want to check that the listener.ora file matches the way you are trying to connect to the DB. If you were connecting via a localhost reference and your listener.ora file got changed from:
HOST = localhost
to
HOST = 192.168.XX.XX
then this can cause the error that you had unless you update your hosts file to accommodate for this. Someone might have made this change to allow for remote connections to the DB from other machines.

I figured out that in my case, my database was in different subnet than the subnet from where i was trying to access the db.

I had this error when i renamed the pc in the windows-properties. The pc-name must be updated in the listener.ora-file

Most probably you have listener configured wrongly, the hostname you specify in connection string must be the same as in the listener.
First check the Firewall and network related issues.
Check if Oracle Listener service is available and running. If not you may use Oracle Net Configuration Assistant tool to add and register new listener.
If the above steps are ok then you need to configure Oracle Listener appropriately. You may use Oracle Net Manager tool or edit “%ORACLE_HOME%\network\admin\listener.ora” file manually.
There are 2 options that need to be considered carefully:
Listening Locations associated with the Listener – Hostname(IP) and Port in Listening Location must exactly match the ones used in the connection string.
For example, if you use 192.168.74.139 as target hostname, then there must be Listening Location registered with the same IP address.
Also make sure the you use the same SID as indicated in Database Service associated with the Listener.
https://adhoctuts.com/fix-oracle-io-error-the-network-adapter-could-not-establish-the-connection-error/

IO Error: The Network Adapter could not establish the connection (CONNECTION_ID=iKQM6lBbSLiArrYuDqud8A==)
if you are facing this issue
1- make sure you have downloaded oracle databases like oracle 11g,19c, 21c, or any latest databases.
2- search for services in your computer or type win+r then services.mis then search for oracleservice you will find orcl or xe or any other sid like oracleserviceorcl;
after that you can test your connection using sql developer, sql plus or cmd

To resolve the Network Adapter Error I had to remove the - in the name of the computer name.

In my case, I needed to specify a viahost and viauser. Worth trying if you're in a complex system. :)

For me the basic oracle only was not installed. Please ensure you have oracle installed and then try checking host and port.

I was having issues with this as well. I was using the jdbc connection string to connect to the database. The hostname was incorrectly configured in the string. I am using Mac, and the same string was being used on Windows machines without an issue. On my connection string, I had to make sure that I had the full url with the appending "organizationname.com" to the end of the hostname.
Hope this helps.

Just try to re-create connection. In my situation one of jdbc connection stopped working for no reason. From console sqlplus was working ok.
It took me 2 hours to realize that If i create the same connection - it works.

How can I monitor/log Tomcat's thread pool?

I have a Tomcat installation where I suspect the thread pool may be decreasing over time due to threads not being properly released. I get an error in catalina.out when maxthreads is reached, but I would like to log the number of threads in use to a file every five minutes so I can verify this hypothesis. Would anyone please be able to advise how this can be be done?
Also in this installation there is no Tomcat manager, it appears whoever did the original installation deleted the manager webapp for some reason. I'm not sure if manager would be able to do the above or if I can reinstall it without damaging the existing installation? All I really want to do is keep track of the thread pool.
Also, I noticed that maxthreads for Tomcat is 200, but the max number of concurrent connections for Apache is lower (Apache is using mod_proxy and mod_proxy_ajp (AJP 1.3) to feed Tomcat). That seems wrong too, what is the correct relationship between these numbers?
Any help much appreciated :D
Update: Just a quick update to say the direct JMX access worked. However I also had to set Dcom.sun.management.jmxremote.host. I set it to localhost and it worked, however without it no dice. If anyone else has a similar problem trying to enable JMX I recommend you set this value also, even if you are connecting from the local machine. Seems it is required with some versions of Tomcat.
Just a quick update to say the direct JMX access worked. However I also had to set Dcom.sun.management.jmxremote.host. I set it to localhost and it worked, however without it no dice. If anyone else has a similar problem trying to enable JMX I recommend you set this value also, even if you are connecting from the local machine. Seems it is required with some versions of Tomcat.

Direct JMX access
Try adding this to catalina.sh/bat:
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=5005
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
UPDATE: Alex P suggest that the following settings might also be required in some situations:
-Dcom.sun.management.jmxremote.host=localhost
This enables remote anonymous JMX connections on port 5005. You may also consider JVisualVM which is much more please and allows to browse JMX via plugin.
What you are looking for is Catalina -> ThreadPool -> http-bio-8080 -> various interesting metrics.
JMX proxy servlet
Easier method might be to use Tomcat's JMX proxy servlet under: http://localhost:8080/manager/jmxproxy. For instance try this query:
$ curl --user tomcat:tomcat http://localhost:8080/manager/jmxproxy?qry=Catalina:name=%22http-bio-8080%22,type=ThreadPool
A little bit of grepping and scripting and you can easily and remotely monitor your application. Note that tomcat:tomcat is the username/password of user having manager-jmx role in conf/tomcat-users.xml.

You can deploy jolokia.war and then retrieve mbeans values in JSON (without the manager):
http://localhost:8080/jolokia/read/Catalina:name=*,type=ThreadPool?ignoreErrors=true
If you want only some values (currentThreadsBusy, maxThreads, currentThreadCount, connectionCount):
http://localhost:8080/jolokia/read/Catalina:name=*,type=ThreadPool/currentThreadsBusy,maxThreads,currentThreadCount,connectionCount?ignoreErrors=true
{
request: {
mbean: "Catalina:name="http-nio-8080",type=ThreadPool",
attribute: [
"currentThreadsBusy",
"maxThreads",
"currentThreadCount",
"connectionCount"
],
type: "read"
},
value: {
currentThreadsBusy: 1,
connectionCount: 4,
currentThreadCount: 10,
maxThreads: 200
},
timestamp: 1490396960,
status: 200
}
Note: This example works on Tomcat7 +.

For a more enterprise solution. I have been using New Relic in our production environment.
This provides a graph of the changes to the threadpool over time.

There are cheaper tools out meanwhile: I am using this jar here: https://docs.cyclopsgroup.org/jmxterm
You can automate it via shell/batch scripts. I regexed the output and let prometheus poll it for displaying it in grafana.