When a user tries joining a TIBCO Data Virtualization node to a cluster, they might face an issue with the below errors logged in the cs_server log:
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1. INFO [jetty thread pool-595360] 2023-05-08 11:50:30.719 +0530 NewStandaloneNode - Start to join a cluster with IP xx.xx.xxx.xx:9407
ERROR [jetty thread pool-595360] 2023-05-08 11:50:30.747 +0530 NewClusterNode - Failed to connect to xx.xx.xxx.xx:9410. Cause:
java.io.IOException: Failed to finish connect: 'No route to host'.[dbchannel-1906503]
...
  
2. ERROR [jetty thread pool-595360] 2023-05-08 11:50:30.747 +0530 NewStandaloneNode - Error joining the cluster: 
com.compositesw.server.cluster.ClusterException: Failed to connect to the remote host xx.xx.xxx.xx at port 9,410. Cause: Failed to finish connect: 'No route to host'.[dbchannel-1906503]  [cluster-2900003]
...

3. INFO [jetty thread pool-595356] 2023-05-08 11:52:26.357 +0530 NewStandaloneNode - Start to join a cluster with xx.xx.xxx.xx:9400
INFO [jetty thread pool-595356] 2023-05-08 11:52:26.396 +0530 NewClusterNode - Cluster state now set to INITIALIZING_LOCAL
WARN [jetty thread pool-595356] 2023-05-08 11:52:26.397 +0530 TCPConfigurationFactory - Failed to resolve IP address of cluster member: host.xyz.com. Cause: java.net.UnknownHostException: host.xyz.com: Name or service not known
...
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All Supported Environments.

"UnknownHostException" come from JDK's InetAddress functions like getAllByName().
Refer to the Javadocs at: https://docs.oracle.com/javase/7/docs/api/java/net/InetAddress.html

getAllByName() takes the name of the host and returns an array of its IP addresses. If there is a problem with accomplishing this, it throws an UnknownHostException. The traces below show the UnknownHostException:
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ERROR [jetty thread pool-426] 2023-04-05 16:14:35.464 +0530 ServerApi - null
java.net.UnknownHostException: 10.90.144.1100: Name or service not known
    at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method) ~[?:?]
    at java.net.InetAddress$PlatformNameService.lookupAllHostAddr(InetAddress.java:929) ~[?:?]
    at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1515) ~[?:?]
    at java.net.InetAddress$NameServiceAddresses.get(InetAddress.java:848) ~[?:?]
    at java.net.InetAddress.getAllByName0(InetAddress.java:1505) ~[?:?]
    at java.net.InetAddress.getAllByName(InetAddress.java:1364) ~[?:?]
    at java.net.InetAddress.getAllByName(InetAddress.java:1298) ~[?:?]
    at java.net.InetAddress.getByName(InetAddress.java:1248) ~[?:?]
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Here, when the user tries pinging the host server using the hostname, it doesn't work, and the ping will fail. But it works if the server is pinged using the IP address instead.
This is due to the failure in resolving the hostname for "host.xyz.com".

So, to summarize, it means TIBCO Data Virtualization cannot resolve the hostname, most likely due to a DNS connectivity issue.

To solve this, the user should verify their DNS configuration for more details and work with the infra/networking team towards solving it.

This article explains the reason behind the mentioned errors while trying to join a cluster in TIBCO Data Virtualization (TDV) and how to solve it.

If the error is: "Error joining the cluster: Request timed out after waiting 5 seconds", refer to this article: https://support.tibco.com/s/article/000046545.