I have Datastax dse running in a Centos VM which is hosted in Microsoft Azure.
Heres the thing: I am unable to ping my host, but can connect to it through ssh(from Ubuntu) or putty(from Windows) just fine. And once I start up dse, I am trying to use Datastax DevCenter to access it.
I have set:
start_native_transport: true
native_transport_port: 9042
start_rpc: true
in cassandra.yaml
And the listen_address and the rpc_address have been set to localhost.
And when I try to connect using DevCenter using the port 9042, I am getting an error indicating that All host(s) tried for query failed. com.datastax.driver.core.TransportException. Cannot connect.
I check the port 9042 and heres the netstat -anp result
tcp 0 0 127.0.0.1:9042 0.0.0.0:* LISTEN -
Can anyone tell me if theres something wrong with my implementation? Im a newbie to Cassandra and datastax btw.
Solution
It was just a firewall issue. Connection can be made when accessing from another network.
Try listen address = blank and rpc address = 0.0.0.0. If that doesn't work, try specifying the external ip for both.
Related
I am facing some issues trying to connect to Cassandra 3.3.0 on Centos 7 remotely from another machine in the network. It is returning a "timed out" error while trying to connect via
$ cqlsh 192.168.1.56 9042
Same with:
$ cqlsh 192.168.1.56
In my point of view, I have configured the cassandra.yaml file correctly as it worked fine when I tried to connect to a locally running VM (Ubuntu) with an active Cassandra instance.
When I am checking the IPs and ports which have been bound via netstat -lnt, it is returning
tcp6 0 0 192.168.1.56:9042 :::* Listen
Actually the only one which is bound to tcp6. 192.168.1.56:9160 is bound to tcp.
Running on Ubuntu, it returns the same binding to tcp. So the fault is related to that point, I guess.
Some background facts:
I am running Cassandra as root. Both server and clients are running cqlsh 5.0.1, CQL spec 3.4.0 and Cassandra 3.3.0. Python 2.7.5.
The VM is accessible via 192.168.1.56 without problems. Firewall is deactivated and I even have tried to de- and reactivate IPv6. I have tried different combinations configuring the cassandra.yaml -- such as taking the interface instead of its IP directly, but without changes in the result.
All my research has not shown success so far. Has anybody an idea?!
Problem has been solved due to network misconfiguration.
I've changed the below configuration in /etc/ssh/sshd_config
Port 22
AddressFamily inet
ListenAddress 0.0.0.0
ListenAddress ::
I've changed AddressFamily from "any" to "inet".
i am trying to run kairosdb and cassandra, but kairosdb shutsdown after i get the following error, i believe it is because kairosdb is not able to establish connection with cassandra. Cassandra seems to be running fine and i cannot understand why this error is popping:
18:33:08.463 [main] ERROR [HConnectionManager.java:71] - Could not start connection pool for host localhost(127.0.0.1):9160
Error injecting constructor, org.kairosdb.core.exception.DatastoreException: me.prettyprint.hector.api.exceptions.HectorException: All host pools marked down. Retry burden pushed out to client. ...
Also, i noticed that kairos_cache ix not created which is mentioned in this link. I changed the permissions of the /tmp/ folder to user from root, still it is not working.
Open your cassandra.yaml file and do the following:
Check if you have the apache thrift rpc server enabled and if it is listening on the port Kairos is listening.
start_rpc: true
rpc_address: localhost
rpc_port: 9160
The message is because KairosDB cannot reach Cassandra.
Probably your cassandra DB is not listening on 127.0.0.1 (loopback).
Check your cassandra.yaml file, probably it is using the IP Adress of your network interface as listen_adress and not 127.0.0.1.
Cassandra only listens on one address, by default it is the local host name of IP.
Otrherwise you may check your port just in case, but the ListenAddress is often the source of this problem.
I had the same issue with a docker deployment of cassandra with KairosDB.
As #JVasques said in his answer, the parameter "start_rpc" is disabled (set to false) in the newest cassandra.yaml file as default.
If anyone needs a default/standard YAML configuration file, it is recommended to download the latest release or the version you are using. You can download it from the official cassandra package on the Apache Website: http://cassandra.apache.org/download/
It is located under conf/cassandra.yaml
Beware: Configuration files of older cassandra versions might not be compatible!
It worked with the following settings in Docker for me:
start_rpc: true
rpc_address: 0.0.0.0
rpc_port: 9160
I have a cassandra node at a machine. When I access cqlsh from the same machne it works properly.
But when I tried to connect to it's cqlsh using "192.x.x.x" from another machine, I'm getting an error saying
Connection error: ('Unable to connect to any servers', {'192.x.x.x': error(111, "Tried connecting to [('192.x.x.x', 9042)]. Last error: Connection refused")})
What is the reason for this? How can I fix it?
Probably the remote Cassandra node is not bound to the external network interface but to the loopback one (this is the default configuration). You can ensure this by using "telnet thecassandrahost 9042" from the remote machine, it should not work.
In order to bind Cassandra to the external network interface you need to edit the cassandra.yaml configuration file and set the properties "listen_address" and "rpc_address" to your remote IP or "0.0.0.0" (not all versions of Cassandra support wildcard addresses).
Check also that the firewall is properly configured or disabled (sudo service iptables stop).
Set the config parameter where this file is located. Possibly /etc/cassandra/cassandra.yaml.
cassandra.yaml
listen_address: 192.x.x.x
rpc_address: 192.x.x.x
Then, restart the service.
1.Update：./conf/cassandra.yaml
rpc_address: 0.0.0.0 ("0.0.0.0" allow anywhere IP,but you can appoint an IP)
\# broadcast_rpc_address: 1.2.3.4 (Delete comment if rpc_address=0.0.0.0)
2.restart
./bin/cassandra
Case: I met a problem that I can't remote access cassandra When I using java access cassandra
I got the same issue. And I am following answer in this post. Unfortunately, I have no luck to make it work. I did some research. And it works now. Here is my change.
Environment
Ubuntu Server 16.04.3 LTS on VirtualBox,
DSE version 5.1
Install DSE
I am installing DSE follow this page
https://docs.datastax.com/en/dse/5.1/dse-dev/datastax_enterprise/install/installGUIdse.html
Go to /etc/dse/cassandra/cassandra.yaml
Change 'seeds' from 127.0.0.1 to {seriver ip} exp. mine is 172.20.10.9
listen_address
In DSE 5.1 official document says 'Never specify 0.0.0.0; it is always wrong.'
What I did is comment out 'listen_address' setting
'rpc_address' change from localhost to 0.0.0.0
'broadcast_address' change to server IP. Mine is 172.20.10.9
'broadcast_rpc_address' change to server ip
restart dse wait for couple minute,it is changing. If still not work, restart machine.
This is my log in 15 seconds.
`ubuntu08#ubuntu08:~$ nodetool status
nodetool: Failed to connect to '127.0.0.1:7199' - ConnectException: 'Connection refused (Connection refused)'.
ubuntu08#ubuntu08:~$ nodetool status
Error: The node does not have system_traces yet, probably still bootstrapping
ubuntu08#ubuntu08:~$ nodetool status
Datacenter: SearchGraphAnalytics
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Address Load Tokens Owns Host ID Rack
UN 10.0.0.44 278.51 KiB 32 ? 19db0016-df63-4470-9921-f3b5fe4e9341 rack1
`
I can access by run 'cqlsh 172.20.10.9' from local or another machine.
This is another document for Cassandra https://docs.datastax.com/en/developer/java-driver/3.3/manual/address_resolution/
I had the same issue, I was not allowed to listen to 0.0.0.0 and Cassandra was running on a VM with Bridged network. The solution I found was to let the VM SSH to itself, port forwarding the port on the bridged network interface to localhost:
ssh -L 192.168.x.x:9042:127.0.0.1:9042 myvmuser#localhost
Since the IP of the bridged network card would change (depending on which developers machine it was run) the ssh-command had to first get the IP, this snipped worked for that:
ifconfig | grep -Eo 'inet (addr:)?([0-9]*\.){3}[0-9]*' | grep -Eo '([0-9]*\.){3}[0-9]*' | grep -v '127.0.0.1'
Also, as this should happen on boot you have to create a SSH key for the vm-user and trust it via .ssh/authorized_keys.
Even after I set the RPC_ADDRESS, it didn't work for me , until I set the -e CASSANDRA_START_RPC=true option.
It was always set to false in my case. I have tried this with Ubuntu, Docker and Cassandra.
Set the following config parameter in cassandra.yaml file (For CentOS it is located in /etc/cassandra/default.conf)
rpc_address: 0.0.0.0
Verify that following values are same as below(usually they are default)
start_native_transport:true
native_transport_port:9042
Last step for CentOS , Update the firewall configuration and allow port 9042 through for incoming connections
Access the firewall from “System / Administration / Firewall” in the CentOS menu
Add the port under “Other Ports”
I edit cassandra.yaml set listen_address and roc_address as ip address resolve the problem.
I set rpc_port to the public IP address, and now I can connect to Cassandra just fine from an outside server.
However, I cannot connect from the Cassandra server itself, using cqlsh
I am getting an error.Thar are:
Connection error: Could not connect to localhost:9160
Is there a configuration, I can change to be able to connect from the server itself ?
Check the cassandra.yaml file on the line with rpc_port : normally by default = 9160
Login to the machine hosting cassandra
Try cqlsh 127.0.0.1 9160 : should be ok in any case
try cqlsh [IP of host] 9160 : if ok then cassandra reachable from lan, if ok then cassandra is not reachable from lan but only localhost 127.0.0.1
You need to connect to cassandra through the rpc_address defined in cassandra.yaml. For example, I use cqlsh 10.0.80.49 9160.
Consider changing /etc/cassandra.yaml:
# Whether to start the thrift rpc server.
start_rpc: false
to
start_rpc: true
if you see this in cassandra logs:
INFO [main] 2015-07-21 12:06:27,426 CassandraDaemon.java:406 - Not starting RPC server as requested. Use JMX (StorageService->startRPCServer()) or nodetool (enablethrift) to start it
then just open a terminal and
$ nodetool enablethrift
as written in the INFO message. Should now work. Got this when my system upgraded to cassandra 2.2.0
If you are on OSX
brew install cassandra
First start the Cassandra
cassandra
Connect via CQL shell
cqlsh 127.0.0.1
Maybe start cassandra on your local machine by bin/cassandra -f first?
It's not listening on 127.0.0.1 since you told it to only listen on <public IP>. Make the listen address 0.0.0.0 to listen on all addresses (or just omit it if possible as this is usually the default). See Listening Sockets .NET tutorial or any other socket tutorial to get a basic understanding of socket binding.
Update (#c45556037):
Note that listen_address is the one for other nodes to use to connect to this one (a misleading name). rpc_address is the actual address to locally bind to. It's unclear from the 2.0 docs and is explained better in the 1.0 docs.
I faced same situation while starting cqlsh . I got following error while starting cassandra
Enter only ----cassandra----- in terminal.
it will show all jars and log files . if terminal hang , just escape from it and then enter cqlsh. then it will enter to cassandra cli.
This worked for me
for 2.0.5 the following works for me ..
$CASSANDRA_HOME/bin/cqlsh xx.xx.xxx.xxx 9160
Exception connecting to localhost/9160. reason: connection refused
Connection refused to cassandra cli mode .
goto the root directory of cassandra :
bin/cassandra -- host {host-ip} --port {9160}
if you are having trouble with this , check your {cassandra-root-directory}/conf/cassandra.yaml
the thrift ip or rpc_address is the address used as the host-ip for connecting to cli .
make it your local IP and if you are having trouble connecting using the port 9160 , try changing the rpc_port to 8070 and now try connecting to cassandra-cli mode using the command
bin/cassandra --host {local-IP} --port 8070
This worked for me, hope it works for you too .
Please execute the below query to resolve the issue
#!/bin/bash
export CASSANDRA_HOME=/opt/apache-cassandra-2.1.8
export CQLSH_HOST=192.168.1.200
export CQLSH_PORT=9042
echo $#
$CASSANDRA_HOME/bin/cqlsh $#'
Make sure to change the IP and location of cassandra Home Directory
Use this command
sudo service cassandra start
to start cassandra and then use
cqlsh command
Consider changing /etc/cassandra-env.sh:
JVM_OPTS="$JVM_OPTS -Dcom.sun.management.jmxremote.ssl=true"
not "true" but "false"
JVM_OPTS="$JVM_OPTS -Dcom.sun.management.jmxremote.ssl=false"
sudo service cassandra restart
How to change default port 9042 in Cassandra ?
I resolved issue using below steps :
1) Stop cassandara services
sudo su -
systemctl stop datastax-agent
systemctl stop opscenterd
systemctl stop app-dse
2) Take backup and Change port from 9042 to 9035
cp /opt/dse/resources/cassandra/conf/cassandra.yaml /opt/dse/resources/cassandra/conf/bkp_cassandra.yaml
vi /opt/dse/resources/cassandra/conf/cassandra.yaml
native_transport_port: 9035
3) Start Cassandra services
systemctl start datastax-agent
systemctl start opscenterd
systemctl start app-dse
4) create cqlshrc file.
vi /root/.cassandra/cqlshrc
[connection]
hostname = 198.168.1.100
port = 9035
OS: CentOS 6.4 (server)
I have successfully installed (yum install dsc20) the cassandra database layer in my server and can connect to it using the CQL SHel (cqlsh). But I need to run queries remotely using the DataStax's DevCenter software. So I installed it (DevCenter) in a separate workstation. (CentOS 6.4 - desktop) and tried to add a new connection in order to connect to the cassandra db.
So I gave the IP of the "CentOS 6.4 - server" (in which cassandra database is running) for the host and the port as 9160. But when testing the connection it fails.
I also tried to turn off the firewall in the server, (/etc/init.d/iptables stop). But was no luck.
I'm sure this may be due to some misconfiguration which I cannot figure out. I'll be grateful, if someone can give me a solution for this as I was researching for this and found no answers. Thank you very much in advance.
DataStax DevCenter being built on top of the DataStax Java driver has the same connectivity requirements as the driver. Namely:
start_native_transport: true
rpc_address: IP or hostname reachable from the client
Machines in the cluster accept connections on port 9042 (the native_transport_port config option)
If rpc_address is set to either a private IP or to 0.0.0.0, DevCenter will not know what node to connect to.
If your cluster has multiple nodes and these are using rpc_address: 0.0.0.0, even if you configure DevCenter with the IP(s) of a couple of nodes, it will still have issues discovering the other nodes in the cluster.
In cassandra.yaml there's a comment/warning about using rpc_address: 0.0.0.0:
Note that unlike ListenAddress above, it is allowed to specify 0.0.0.0
here if you want to listen on all interfaces, but that will break clients
that rely on node auto-discovery.
Note: it is possible that in the future DevCenter might be able to ignore/filter out nodes in the cluster configured with rpc_address: 0.0.0.0.
Try this.. It worked for me!
Run the following command on your machine where you have DevCenter installed
$> ssh -L 9042:localhost:9042 <username>#<ip-address-cassandra-db> -N
After running this command, it will prompt for password
Now in your DevCenter > Contact Hosts, provide "127.0.0.1" and test connection. Bingo, you see the magic...
In the cassandra.yaml, I set
listen_address: localhost
rpc_address: 1.2.3.4
broadcast_rpc_address: 1.2.3.4
After doing a
sudo service cassandra restart
DevCenter was able to successfully connect.
After this change, cqlsh would not start without the address:
cqlsh 1.2.3.4
You can set the environment variable $CQLSH_HOST=1.2.3.4. Then simply type cqlsh.
If there's somebody working with docker locally, it can run this command.
docker run --name cassandra -p 127.0.0.1:9042:9042 -p 127.0.0.1:9160:9160
-e CASSANDRA_LISTEN_ADDRESS=localhost
-e CASSANDRA_BROADCAST_ADDRESS=localhost
-e CASSANDRA_RPC_ADDRESS=localhost -d cassandra