Develop Reference

jsch ssh connection can't get authorized_keys

i'm trying to make a connection via ssh from windows to a unix server
my goal to have it in my java app so i cann run command without inputting passwords on each connect
right now i'm trying to understand what i'm doing wrong with keys
I generated a key in Tectia and uploaded it to server;
I can see it in .ssh as 2798 Apr 17 10:56 authorized_keys
my connection setup looks like this
...
JSch jsch = new JSch();
jsch.setKnownHosts("~/.ssh/know_hosts");
jsch.addIdentity("~/.ssh/authorized_keys");
System.out.println("identity added ");
Session session=jsch.getSession(user, host, 22);
session.setConfig("PreferredAuthentications", "publickey");
System.out.println("session created.");
session.connect();
System.out.println("Connected");
....
and as a result of this i'm getting this error
com.jcraft.jsch.JSchException: java.io.FileNotFoundException:
C:\Users\User\ .ssh\authorized_keys (The system cannot find the path
specified)
it's looking for the key on my local computer and not connecting to the server
what am I going wrong with these keys ?

The argument to addIdentity is a local path to your private key.
Instead, you are giving it a path to a file that:
Would contain a public key;
Does not exit locally anyway.

Copy files from local window machine to remote windows machine using java

I have searched a lot but couldn't get a solution for this. I need to copy a file from local windows machine to remote windows machine using java program. I have tried with JSch,
JSch jsch = new JSch();
Session session = null;
session = jsch.getSession("username","hostname",22);
session.setPassword("password");
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
ChannelSftp channel = null;
channel = (ChannelSftp)session.openChannel("sftp");
channel.connect();
File localFile = new File("filePath");
//If you want you can change the directory using the following line.
channel.cd("E:/xxx");
channel.put(new FileInputStream(localFile),localFile.getName());
channel.disconnect();
session.disconnect();
While executing the above code, i am facing the below error,
Exception in thread "main" 2: No such file
at com.jcraft.jsch.ChannelSftp.throwStatusError(ChannelSftp.java:2846)
at com.jcraft.jsch.ChannelSftp._realpath(ChannelSftp.java:2340)
at com.jcraft.jsch.ChannelSftp.cd(ChannelSftp.java:342)
I have cygwin installed in remote windows machine. It seems Jsch is not able to find the windows path. The same code works properly when copying files from windows machine to linux machine.
Please tel me a solution for the above problem or is there any other options for this to achieve in java ? Thanks

In order to resolve a Windows path with a drive letter you may need to use the /cygdrive prefix. In this case, your cd method call should be called with the parameter /cygdrive/e/xxx.

Apache Connection Refused when running Docker-client Java API

I am trying to install the Docker-client Remote API library ( https://github.com/spotify/docker-client ) to do some image searches and inspect image data (all in public repositories). I have the boot2docker VM downloaded, installed and running. Commands such as "Docker pull ubuntu" work fine but I would like to do this via a Java program now. I used the Eclipse IDE Egit plugin to import the github project and created a Maven/Java project from the existing Master branch. The source code is completely imported and no errors reported. I then tried writing a simple test:
final DockerClient docker = DefaultDockerClient.fromEnv().build();
//docker.pull("busybox");
List<ImageSearchResult> results = docker.searchImages("ubuntu");
for (ImageSearchResult res : results) {
System.out.println(res.getName());
}
However, when running the code in Eclipse I get the following error:
Exception in thread "main" com.spotify.docker.client.DockerException: java.util.concurrent.ExecutionException: javax.ws.rs.ProcessingException: org.apache.http.conn.HttpHostConnectException: Connect to localhost:2375 [localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1] failed: Connection refused: connect
at com.spotify.docker.client.DefaultDockerClient.propagate(DefaultDockerClient.java:1109)
at com.spotify.docker.client.DefaultDockerClient.request(DefaultDockerClient.java:1028)
at com.spotify.docker.client.DefaultDockerClient.searchImages(DefaultDockerClient.java:653)
at com.spotify.docker.client.main.Test.main(Test.java:28)
I tried setting up an apache server on that port but then I get:
Exception in thread "main" com.spotify.docker.client.DockerRequestException: Request error: GET http://localhost:2375/v1.12/images/search?term=ubuntu: 404
at com.spotify.docker.client.DefaultDockerClient.propagate(DefaultDockerClient.java:1100)
at com.spotify.docker.client.DefaultDockerClient.request(DefaultDockerClient.java:1028)
at com.spotify.docker.client.DefaultDockerClient.searchImages(DefaultDockerClient.java:653)
at com.spotify.docker.client.main.Test.main(Test.java:28)
Can anyone tell me what I am supposed to do here to make my search/pull call work? This is my first try with Docker and I've searched through the documentation and googled the problem but can't find anyone with a similar problem.
Thank you!
EDIT: I am running docker in Windows 7 via the pre-built VM Boot2Docker. Maybe the Docker daemon running inside that is not accessible from programs outside of the VM such as Eclipse?
EDIT: solved it by upgrading to v1.6 instead of v1.5 which makes the daemon available in the Windows host. Current problem is that all my API calls are returning "The server failed to respond with a valid HTTP response"

I encountered a similar issue and I managed to solve this issue by using the following way, to build up the DockerClient:
final DockerClient docker = DefaultDockerClient.builder()
.uri(URI.create("unix:///var/run/docker.sock"))
.build();
I had been getting the same exception but adding the above URI part helped me to solve the issue.
A better explanation for a issue similar to the above and how to solve it has been provided in the following issue tracker.
https://github.com/spotify/docker-maven-plugin/issues/61

The Java program does essentially a docker search: that can only work in an environment where the docker engine is present.
Either in the boot2docker VM.
Or in a full Linux host.

I did encounter the same problem on Mac with eclipse and Docker version 1.10.3, I did search for a solution before I settled for a workaround - Using docker CLI docker-manager to create a new virtualbox and get the DOCKER_HOST and DOCKER_CERT_PATH values of that virtualbox and create a new builder.
In my case: I have created a virtual box default2 using docker CLI command docker-machine create -d virtualbox default2
Docker CLI
$ docker-machine env
export DOCKER_TLS_VERIFY="1"
export DOCKER_HOST="tcp://192.168.99.103:2376"
export DOCKER_CERT_PATH="/Users/XXXX/.docker/machine/machines/default2"
export DOCKER_MACHINE_NAME="default2"
Docker-client JAVA
DockerCertificates defaultCertificates = new DockerCertificates(Paths.get("/Users/XXXX/.docker/machine/machines/default2"));
DockerClient docker = DefaultDockerClient.builder()
.uri("https://192.168.99.103:2376")
.dockerCertificates(defaultCertificates)
.build();

How to configure hadoop with eclipse

I am new in hadoop I have downloaded the hortonworks sanbox image and mounted that with virtualBox. And sanbox ui is coming in the localhost when I am typing 192.168.56.101/ in the Chrome. Also I am able to log in to hadoop shell with hue/hadoop username password. Now I want to run a simple program in eclipse. I have added hadoop-0.18.3-eclipse-plugin to the eclipse and then tried the following steps.
1.choosed map/reduce from eclipse.
2.went to hadoop location editer
localhost name:localhost
under map/reduce master
port:9000
under DFS master
port:9001
But I am getting this error
Cannot connect to the Map/Reduce location: localhost Call to
localhost/127.0.0.1:9001 failed on connection exception:
java.net.ConnectException: Connection refused: no further information
Virtual box is running.

Add required hadoop dependancy jar files to your eclipse class path.
In your main method of your mapreduce program add these lines
Configuration conf = new Configuration();
conf.set("fs.default.name", "hdfs://localhost:50000");
conf.set("mapreduce.job.tracker", "localhost:50001");
if you are running in virtual machine change the localhost to
required ip address (where hadoop demon runs).you can get the ip
address bytyping ifconfig
run the mapreduce program as simple java program
.you will get the output in the eclipse console.

How can I start apache derby programmatically jar file?

I have a Java application, which uses Apache Derby. Using Eclipse Export option, I exported it as JAR file. When I am running Eclipse, and the server is connected to port 1527, the JAR executes correctly.
However when eclipse is closed, (and the server is not connected to 1527) on executing jar, i get this error
java.sql.SQLNonTransientConnectionException: java.net.ConnectException
: Error connecting to server localhost on port 1527 with message
Connection refused.
This is understandable. But i want to distribute the JAR. So is there a way to start the server programmatically, whenever JAR is executed?

You can start the NetworkServer programmatically:
NetworkServerControl serverControl = new NetworkServerControl(InetAddress.getByName("myhost"),1621)
serverControl.shutdown();

Simplest is to use embedded Derby
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
conn = DriverManager.getConnection("jdbc:derby:" + DATA_STORE + ";create=true");

You need to start the server programmatically.
How this is done is documented in the manual:
http://db.apache.org/derby/docs/10.8/adminguide/tadminconfig814963.html