how to verify that the native transport port default 9042 on each node is open to the machine running opscenterd
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Cluster nodes
To check if a DSE node is accepting connections on CQL port 9042, you can use either the Linux netstat or lsof utilities.
In this sample netstat output, the DSE process ID is 23773 and port 9042 is bound to IP 10.101.34.115:
$ netstat -tlnp Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN - tcp 0 0 10.101.34.115:7000 0.0.0.0:* LISTEN 23773/java tcp 0 0 127.0.0.1:7199 0.0.0.0:* LISTEN 23773/java tcp 0 0 10.101.34.115:8609 0.0.0.0:* LISTEN 23773/java tcp 0 0 127.0.0.1:45609 0.0.0.0:* LISTEN 23773/java tcp 0 0 10.101.34.115:9042 0.0.0.0:* LISTEN 23773/java tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN - tcp6 0 0 :::22 :::* LISTEN -
Specifically this line:
tcp 0 0 10.101.34.115:9042 0.0.0.0:* LISTEN 23773/java
Here's an example lsof output:
$ sudo lsof -nPi -sTCP:LISTEN COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME systemd-r 988 systemd-resolve 13u IPv4 18580 0t0 TCP 127.0.0.53:53 (LISTEN) sshd 1575 root 3u IPv4 24868 0t0 TCP *:22 (LISTEN) sshd 1575 root 4u IPv6 24873 0t0 TCP *:22 (LISTEN) java 23773 ubuntu 852u IPv4 128787223 0t0 TCP 10.101.34.115:8609 (LISTEN) java 23773 ubuntu 854u IPv4 128787233 0t0 TCP 127.0.0.1:7199 (LISTEN) java 23773 ubuntu 855u IPv4 128787236 0t0 TCP 127.0.0.1:45609 (LISTEN) java 23773 ubuntu 918u IPv4 128795863 0t0 TCP 10.101.34.115:9042 (LISTEN) java 23773 ubuntu 1114u IPv4 128790715 0t0 TCP 10.101.34.115:7000 (LISTEN)
Specifically this line:
java 23773 ubuntu 918u IPv4 128795863 0t0 TCP 10.101.34.115:9042 (LISTEN)
OpsCenter
To check if the OpsCenter has connectivity to the DSE nodes, use Linux utilities such as telnet or nc.
Here's an example output running telnet on the OpsCenter server:
$ telnet 10.101.34.115 9042 Trying 10.101.34.115... Connected to 10.101.34.115. Escape character is '^]'.
If DSE is not running or a firewall is blocking access to the port, you will get this error:
telnet: Unable to connect to remote host: Connection refused
Cheers!
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