I am running a standalone hadoop/hbase cluster on EC2.
Everything is running fine however when I restart, I get messages such as 2014-03-18 12:41:53,401 INFO org.apache.hadoop.ipc.HBaseRPC: Problem connecting to server: ip-10-73-158-244.eu-west-1.compute.internal/10.73.158.244:39781 and eventually hbase shuts down.
This seems to be caused due the fact the the dns record no longer exists but why does HBase look for the old record in the first place? My hbase-site.xml has
<property>
<name>hbase.rootdir</name>
<value>hdfs://127.0.0.1:9000/hbase</value>
</property>
Any ideas how I can resolve this?
Related
so i have a DNS server with my code running on it. when first depolyed the server it was running with a free cluster from mongodb but now i changed the free cluster to a mongodb running on the DNS server. i changed the connection string and it works locally just fine. but when pulling the changes with SSH to my DNS server it still takes the data from the old free cluster although notihng inthe code points into it. i have tried to check if changes are happening when pulling from ssh and they are. just the database connection stay with the old one. what could be the problem? should i restart the server or some service?
First time using cassandra, I have attempted to configue the yaml file according to other related posts but had no luck so far. Any idea how do so on the localhost?
The specified host(s) could not be reached.
All host(s) tried for query failed (tried: localhost/0:0:0:0:0:0:0:1:9042 (com.datastax.driver.core.TransportException: [localhost/0:0:0:0:0:0:0:1:9042] Cannot connect), localhost/127.0.0.1:9042 (com.datastax.driver.core.TransportException: [localhost/127.0.0.1:9042] Cannot connect))
[localhost/0:0:0:0:0:0:0:1:9042] Cannot connect
[localhost/127.0.0.1:9042] Cannot connect
Inverse the process(s) you already executed. To run cassandra on localhost, you don't need to change anything so far. You don't need to change cassandra.yaml. It'll run by default on localhost. Read the documents carefully.
Learn more about cassandra.yaml:https://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configCassandra_yaml_r.html
Maybe you can stop the Cassandra server and start it again.
bin/cassandra -f -R
Further this link helps understand
https://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configCassandra_yaml_r.html
cassandra.yaml config parameters.
You can also make sure that the ports are set correctly native_transport(9042),native_transport_port_ssl(9142),Storage_port(7000),roc_port(9160) and JMX port(7199).
Lastly,
seeds - "127.0.0.1"
assuming you are working on single node cassandra setup.
Might be your DataStax Cassandra Community Server windows service is stopped. So, start it and reconnect. i hope you get success.
While you are trying to start this service and if it would stopped again then you have to delete the logs folder (where DataStax installed) and restart this service.
My configuration are:
1 Spark machine on EC2: c3.2xlarge.
Communicating with 4 nodes of Cassandra on EC2.
I am getting the following error:
16/08/03 22:41:10 ERROR Session: Error creating pool to /XX.XX.XXX.XX:9042
com.datastax.driver.core.TransportException: [/XX.XX.XXX.XX:9042] Cannot connect
The XX are the public IP of the EC2 cassandra.
However inside my spark configuration: Im telling spark to use the seeder internal IP node, which then the spark-connector driver receive the information from Cassandra the public IP.
How my IT set the clusters up, I am assuming the following:
ERROR Session: Error creating pool to /127.0.0.1:9042
However I don't want to have my clusters connect via public IP and open up the firewall. I would like to have it stay to the internal IP of the cluster.
Is there a way to do this Spark code level wise or cassandra.yml configuration wise?
My objective is to access my Hbase cluster on Azure with Squirrel with a Phoenix driver running on my local computer.
My Hbase cluster on Azure is operational. I can see it in the Ambari dashboard and I can access it using SSH. I can start Phoenix with the sqlline.py command pointing to one of the zookeeper nodes. The !tables command returs four lines.
My Hbase cluster is included in an Azure VNet. From my local computer (running Windows 10) I can connect to this VNet. I can ping the IP address (10.254.x.x) of the zookeeper node successfully but pinging the FQDN of the zookeeper node results in an error message:
"Ping request could not find host zk1-.......ax.internal.cloudapp.net.
Please check the name and try again."
When I start Squirrel on my local computer with the URL pointing to the FQDN of the zookeeper node I get an error message:
"Unexpected Error occurred attempting to open an SQL connection". The
stack trace points to a java.util.concurrent.RuntimeException: "Unable
to establish connection"
When I start Squirrel on my local computer with the URL pointing to the IP address of the zookeeper node I get a different error:
"Unexpected Error occurred attempting to open an SQL connection". The
stack trace points to a java.util.concurrent.TimeoutException.
I suspect this has something to do with the Domain Name resolution problem as described here [https://superuser.com/questions/966832/windows-10-dns-resolution-via-vpn-connection-not-working]. I applied the resolution as described by LikeARock47 on Feb 23. This did not improve the situation however.
Does this indeed have to do with the Domain Name resolution issue or is the problem somewhere else?
Is there a better solution to the Domain Name resolution issue?
A JDBC connection from Squirrel on my local Windows10 computer has succesfully been established to the Hbase cluster by using the zookeeper IP address and the port and "/hbase-unsecure":
jdbc:phoenix:10.254.x.x:2181:/hbase-unsecure
I can manage my HBase cluster with a local Squirrel now!
I'd still be interested to find out how I can get the zookeeper FQDN resolved locally.....
I have setup Cassandra, and I've created a keyspace('mykeyspace') and a table in it. I started Cassandra as a service, added the cassandra.properties file like this, in the presto installation files:
connector.name=cassandra
cassandra.contact-points=localhost
cassandra.native-protocol-port=9142
cassandra.thrift-port=9160
After this I have issued this command in Presto but I'm not sure if it is connecting to the Cassandra data:
./presto --server localhost:8080 --catalog cassandra --schema mykeyspace
Now, when I give the command 'show tables', I get this Exception-message:
All host(s) tried for query failed (tried: localhost/127.0.0.1 (com.datastax.driver.core.TransportException: [localhost/127.0.0.1] Cannot connect))
I have used cqlsh, to view a created table in 'mykeyspace' in cassandra, and hence sure that cassandra is running.
I would really appreciate any help to clear this error.
If you have a default cassandra installation, the dafault native protocol port is 9042. If that is the case, you can remove cassandra.native-protocol-port and cassandra.thrift-port properties.
If you want to keep this ports, you can change cassandra.yaml configuration file, property native_transport_port
I hope it's helps.