Tips on troubleshooting WebHbase connection through Knox.

[#1]

1. Make sure webhbase is running:

[root@ambari-server]# curl http://localhost:60080/version
rest 0.0.3 [JVM: Oracle Corporation 1.8.0_60-25.60-b23] [OS: Linux 2.6.32-504.el6.x86_64 amd64] [Server: jetty/6.1.26.hwx] [Jersey: 1.9] 

2. If the webhdfs REST daemon is not running then you will need to start it.

[root@ambari-server]# /usr/hdp/current/hbase-client/bin/hbase-daemon.sh start rest -p 60080
starting rest, logging to /var/log/hbase/hbase-root-rest-ambari-server.support.com.out 

[root@ambari-server security]# ps -ef | grep 60080
root     19147     1  0 20:17 pts/1    00:00:00 bash /usr/hdp/current/hbase-client/bin/hbase-daemon.sh --config /usr/hdp/current/hbase-client/bin/../conf foreground_start rest -p 60080
root     19161 19147 28 20:17 pts/1    00:00:03 /usr/jdk64/jdk1.8.0_60/bin/java -Dproc_rest -XX:OnOutOfMemoryError=kill -9 %p -Dhdp.version=2.3.4.0-3485 -XX:+UseConcMarkSweepGC -XX:ErrorFile=/var/log/hbase/hs_err_pid%p.log -Djava.security.auth.login.config=/usr/hdp/current/hbase-regionserver/conf/hbase_client_jaas.conf -Djava.io.tmpdir=/tmp -verbose:gc -XX:+PrintGCDetails -XX:+PrintGCDateStamps -Xloggc:/var/log/hbase/gc.log-201605312017 -Dhbase.log.dir=/var/log/hbase -Dhbase.log.file=hbase-root-rest-ambari-server.support.com.log -Dhbase.home.dir=/usr/hdp/current/hbase-client/bin/.. -Dhbase.id.str=root -Dhbase.root.logger=INFO,RFA -Djava.library.path=:/usr/hdp/2.3.4.0-3485/hadoop/lib/native/Linux-amd64-64:/usr/hdp/2.3.4.0-3485/hadoop/lib/native -Dhbase.security.logger=INFO,RFAS org.apache.hadoop.hbase.rest.RESTServer -p 60080 start 

3. Test the webhbase call through knox. (https://cwiki.apache.org/confluence/display/KNOX/Examples+HBase)

[root@ambari-slave2 topologies]# curl -ik -u admin:admin-password -H "Accept: text/xml" -X GET 'https://localhost:8443/gateway/default/hbase/version'
HTTP/1.1 200 OK
Set-Cookie: JSESSIONID=vs8e1emsk00h1va2vk5aeq2b9;Path=/gateway/default;Secure;HttpOnly
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Cache-Control: no-cache
Content-Type: text/xml
Content-Length: 192
Server: Jetty(8.1.14.v20131031)
<?xml version="1.0" standalone="yes"?><Version JVM="Oracle Corporation 1.8.0_60-25.60-b23" REST="0.0.3" OS="Linux 2.6.32-504.el6.x86_64 amd64" Server="jetty/6.1.26.hwx" Jersey="1.9"></Version>