How to enable cassandra port to connect with BI application. Here my setup with cassandra is of multiple nodes (192.xxx.xx.01,192.xxx.xx.02,192.xxx.xx.03). In this scenario which node will be acting like master / coordinator with my application.
Although i worked with listen_address, rpc_address, broadcast_rpc_address and seeds, I opened both tcp ports 9042 and 9160.
version: 3.10
Kindly, lead me to the right direction.
Cassandra uses master-less architecture.All nodes are equal in cassandra.
When you connect to one of the node that node act as co-ordinator node, any of the node can be co-ordinator.
The coordinator is selected by the driver based on the policy you have set. Common policies are DCAwareRoundRobinPolicy and TokenAware Policy.
For DCAwareRoundRobinPolicy, the driver selects the coordinator node based on its round robin policy. See more here: http://docs.datastax.com/en/drivers/java/2.1/com/datastax/driver/core/policies/DCAwareRoundRobinPolicy.html
For TokenAwarePolicy, it selects a coordinator node that has the data being queried - to reduce "hops" and latency. More info: http://docs.datastax.com/en/drivers/java/2.1/com/datastax/driver/core/policies/TokenAwarePolicy.html
native_transport_port is 9042 by default and clients use native transport by default.
Hence you should have connection from your BI to Cassandra host on port 9042.
Related
I'm trying to control the access to Cassandra database so it can be accessed from specific hosts only (deny the access from not configured hosts ), I have the following configurations in cassandra.yaml file:-
start_rpc: true
rpc_address: 0.0.0.0
broadcast_rpc_address: x.x.x.x
rpc_port:9160
Are these configurations are correct or there is something missing? AND is there another way to access Cassandra from specific hosts?
Not sure which version of Cassandra you are using, but 9160 is for thrift protocol connections. It's been deprecated in Cassandra 3.0, and removed in Cassandra 4.0.
If it were me, I'd be closing that avenue of access by setting start_rpc: false.
All client connection requests should be using the CQL native binary protocol on port 9042 (9142 if client-to-node SSL is used in v4.0+).
control the access to Cassandra database so it can be accessed from specific hosts only
For this, your best option would be to filter with iptables on each node. Here's a resource which details how to do that. Basically, you'll need to ACCEPT connections to/from each IP address, on each node in the cluster:
Allow incoming connections from 192.168.0.1, only on port 9042:
iptables -A INPUT -s 192.168.0.1 --dport 9042 -j ACCEPT
Allow outgoing connections back to 192.168.0.1:
iptables -A OUTPUT -d 192.168.0.1 -j ACCEPT
I want to echo Aaron's comments. Thrift was deprecated and replaced by CQL in 2012. Support for Thrift in the Cassandra tools was dropped in 2014 (CASSANDRA-8358) and the Thrift RPC server was disabled by default since Cassandra 2.2 (CASSANDRA-9319).
Development on Thrift clients also ceased nearly 10 years ago. Nate McCall who is the current Chair of the Cassandra project and author of the Hector client closed it down in 2015 in preference for the Java driver so I wouldn't use Thrift anymore.
Instead of the Thrift server, you should configure the CQL native transport server. These are the properties you should focus on in cassandra.yaml:
listen_address: private_ip
rpc_address: public_ip
native_transport_port: 9042
If your nodes only have a single IP address, you can use it for both listen_address and rpc_address. It isn't really necessary to use broadcast_address unless you have a complicated network topology where nodes can only talk to nodes in a remote DC using public IP addresses, for example with EC2 multi-region deployments.
Your question isn't really about Cassandra but about networking. You need to talk to your network admin to configure the firewalls to only allow connections to port 9042 from the application servers. Cheers!
I have 10 Cassandra Nodes running on Kubernetes on my server and 1 contact point that expose the service on port 10023.
However, when the datastax driver tries to establish a connection with the other nodes of the cluster it uses the exposed port instead of the default one and i get the following error:
com.datastax.driver.core.ConnectionException: [/10.210.1.53:10023] Pool was closed during initialization
Is there a way to expose one single contact point and have it to communicate with the other nodes on the standard port (9042)?
i checked on the datastax documentation if there is anything related to it but i didn't find much.
this is how i connect to the cluster
Cluster.Builder builder = Cluster.builder();
builder.addContactPoints(address)
.withPort(Integer.valueOf(10023))
.withCredentials(user, password)
.withMaxSchemaAgreementWaitSeconds(600)
.withSocketOptions(
new SocketOptions()
.setConnectTimeoutMillis(Integer.valueOf(timeout))
.setReadTimeoutMillis(Integer.valueOf(timeout))
).build();
Cluster cluster = builder.withoutJMXReporting().build();
Session session = cluster.connect();
After driver contacts first node, it fetches information about cluster, and use this information, and this information includes on what ports Cassandra listens.
To implement what you want to do, you need that Cassandra listened on the corresponding port - this is configured via native_transport_port parameter of the cassandra.yaml.
Also, by default Cassandra driver will try to connect to all nodes in cluster because it uses DCAware/TokenAware load balancing policy. If you want to use only one node, then you need to use WhiteListPolicy instead of default policy. But is not optimal from the performance point of view.
I would suggest to re-think how you expose Cassandra to clients.
I have a question about Cassandra.
Is it possible to open Cassandra client connection on many IPs?
On my server I have 2 network cards (eth0 and eth1) with IP 10.197.11.21 (eth0) and 192.168.0.45 (eth1) and 127.0.0.1 (lo).
I want my client to connect to Cassandra database with this three IP
in localhost, 10.197.11.21 and 192.168.0.45
For the moment I can choose only 1 IP, what does it do to modify in the file cassandra.yaml ?
You need to set rpc_address: 0.0.0.0 in cassandra.yaml
Note that when you set rpc_address to 0.0.0.0, you also must set broadcast_rpc_address to something other than 0.0.0.0 (e.g. 10.197.11.21).
rpc_address is the address that Cassandra listens on for connections from clients
listen_address is the address that Cassandra listens on for connections from other Cassandra nodes (not client connections)
broadcast_rpc_address is the address that Cassandra broadcasts to clients that are attempting to discover the other nodes in the cluster. When an application first connects to a Cassandra cluster, the cluster sends the application a list of all the nodes in the cluster, and their IP addresses. The IP address sent to the application is the broadcast_ip_address (side-note: cassandra actually sends all IP addresses, this is just the one that it tells the client to connect on). This allows the application to auto-discover all the nodes in the cluster, even if only one IP address was given to the application. This also allows applications to handle situations like a node going offline, or new nodes being added.
Even though your broadcast_rpc_address can only point to one of those two IP addresses, you application can still connect to either one. However, your application will also attempt to connect to other nodes via the broadcast_rpc_addresses sent back by the cluster. You can get around this by providing a full list of the address of every node in the cluster to your application, but the best solution is to build a driver-side address translator.
Now I am trying BAM 2.3.0 and I want to know the way to connect to BAM internal Cassandra from different server. Is it possible or it is tightly coupled?
No it is not tightly coupled. Similar to making standalone Cassandra cluster you must do the configuration but since you not creating a cluster but to access from external server no need to give seed addesses. Just configure the listen and rpc address. The location of the cassandra.yaml is BAM_HOME/repository/conf/etc.
In the cassandra.yaml change listen_address and rpc_address to your IP address. If you put 127.0.0.1 the Cassandra will only listen to the connections coming from the localhost, therefore you cannot access from outside.
I have installed Apache Cassandra on the remote Ubuntu server. How to allow remote access for an Apache Cassandra database? And how to make a connection?
Remote access to Cassandra is via its thrift port (although note that the JMX port can be used to perform some limited operations).
The thrift port is defined in cassandra.yaml by the rpc_port parameter, which defaults to 9160. Your cassandra node should be bound to the IP address of your server's network card - it shouldn't be 127.0.0.1 or localhost which is the loopback interface's IP, binding to this will prevent direct remote access. You configure the bound address with the rpc_address parameter in cassandra.yaml. Setting this to 0.0.0.0 says "listen on all network interfaces" which may or may not be suitable for you.
To make a connection you can use:
The cassandra-cli in the cassandra distribution's bin directory provides simple get / set / list operations and depends on Java
The cqlsh shell which provides CQL access to cassandra, this depends on Python
A higher level interface such as Apollo
For anyone finding this question now, the top answer is out of date.
Apache Cassandra's thrift interface is deprecated and will be removed in Cassandra 4.0. The default client port is now 9042.
As noted by Tyler Hobbs, you will need to ensure that the rpc_address parameter is not set to 127.0.0.1 or localhost (it is localhost by default). If you set it to 0.0.0.0 to listen on all interfaces, you will also need to set broadcast_rpc_address to either the node's public or private IP address (depending on how you plan to connect to Cassandra)
Cassandra-cli is also deprecated and Apollo is no longer active. Use cqlsh in lieu of cassandra-cli and the Java driver in lieu of Apollo.
I do not recommend making the JMX port accessible remotely unless you secure it properly by enabling SSL and strong authentication.
Hope this is helpful.
cassandra 3.11.3
I did the following to get mine working. Changes in cassandra.yaml :
start_rpc: true
rpc_address: 0.0.0.0
broadcast_rpc_address: ***.***.***.***
broadcast_rpc_address is the address of machine where cassandra is installed
seed_provider:
- class_name: ...
- seeds: "127.0.0.1, ***.***.***.***"
In seeds i added/appended the ip address of machine where cassandra was running.
I accessed it from windows using tableplus. In tableplus, I wrote the ip address of the cassandra machine, in the port section I wrote 9042 and used the username and password, which i used for ssh connection.
For anyone using Azure, the issue may be that you need to create a public ip address since the virtual ip points to the cloud service itself and not the virtual machine. You can find more info in this post