Wiktor Kubicki created NIFI-10221: ------------------------------------- Summary: Nifi does not respect multirecord domain in hostname field. Key: NIFI-10221 URL: https://issues.apache.org/jira/browse/NIFI-10221 Project: Apache NiFi Issue Type: Bug Affects Versions: 1.16.0 Reporter: Wiktor Kubicki
*Short description:* Using DNS we are able to add multiple A records with several IP addresses to domain, but Nifi use always only (first?) one. *Background:* We can add multiple A records in DNS to provide round robin "load balancer", which can also be used as failover server in Active - Active server schema. A good example of that implementation is there: [How To Configure DNS Round-Robin Load-Balancing For High-Availability | DigitalOcean|https://www.digitalocean.com/community/tutorials/how-to-configure-dns-round-robin-load-balancing-for-high-availability]. We use this solution to provide address to our two sFTP servers in different geographical locations. {*}How it works now{*}: When i put domain into hostname field in listSFTP, Nifi will solve DNS and obtain only one address (probably the first one but i cannot comfirm) and connect to it. But when this one IP is unreachable, NiFi will not try with second one nor try the second one in any next run. *How it should works:* Addresses should be used randomly (round robin), and if one is unavailable, then in the same run should be tried another one till end of IP's or successful connection. {*}Example{*}: Using sftp client (OpenSSH_7.4p1, OpenSSL 1.0.2k-fips 26 Jan 2017) i can connect to host by domain, even if one of IP addresses is down: {code:java} $ sftp -vvv -oPort=22 u...@example.com OpenSSH_7.4p1, OpenSSL 1.0.2k-fips 26 Jan 2017 debug1: Reading configuration data /XXX/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 58: Applying options for * debug2: resolving "example.com" port 22 debug2: ssh_connect_direct: needpriv 0 debug1: Connecting to example.com [X.X.X.203] port 22. debug1: connect to address X.X.X.203 port 22: Connection refused debug1: Connecting to example.com [Y.Y.Y.123] port 22. debug1: Connection established.{code} As you can see, sftp tries to connect to first, when connections refused then it try to second one with success. And that's how it should work in NiFi -- This message was sent by Atlassian Jira (v8.20.10#820010)