Host disconnected due to different workflow configuration
Hello all, I experienced "host out of the cluster which was no longer able to join", log reports configuration workflow has been changed and it's different from the one running into the cluster. Due to this issue there is not way to join again the cluster. To resolve this I stopped the whole cluster and copied the same configuration to every host. After the restart anything worked well. Is here a good way to prevent flow changes when all the host into the cluster are not connected ?
Re: Host disconnected due to different workflow configuration
Hello, In general NiFi does its best to prevent changes being made to the flow when one of the cluster nodes is down. For example, if you have a 3 node cluster and only 2 nodes are up, you can't change the flow. When a request comes in to change the flow, lets say you drag a new processor on the graph, this is sent to one of the nodes which then does a two phase-commit with the rest of the nodes in the cluster. The error message you got means that all the nodes responded successfully to the first phase, and on the second phase of the commit, one of the nodes encountered an error. At this point the change was applied to the other nodes, and the node with the error was purposely disconnected from the cluster because it is in an inconsistent state. If possible, can you see what other errors happened in the log of that node before seeing "host out of cluster..."? because the real problem is there was some other issue on that node that caused it to fail. -Bryan On Wed, Nov 9, 2016 at 5:45 AM, Alessio Palma < alessio.pa...@docomodigital.com> wrote: > Hello all, > > I experienced "host out of the cluster which was no longer able to > join", log reports configuration workflow has been changed and it's > different from the one running into the cluster. > Due to this issue there is not way to join again the cluster. > To resolve this I stopped the whole cluster and copied the same > configuration to every host. After the restart anything worked well. > Is here a good way to prevent flow changes when all the host into the > cluster are not connected ? > > >
Re: Host disconnected due to different workflow configuration
OK, understood it. It's still a bit fragile. Is there a way to force the adoption of a configuration from a node using the mouse without to stop and start the server ? From: Bryan Bende Sent: Thursday, November 10, 2016 3:19:16 PM To: users@nifi.apache.org Subject: Re: Host disconnected due to different workflow configuration Hello, In general NiFi does its best to prevent changes being made to the flow when one of the cluster nodes is down. For example, if you have a 3 node cluster and only 2 nodes are up, you can't change the flow. When a request comes in to change the flow, lets say you drag a new processor on the graph, this is sent to one of the nodes which then does a two phase-commit with the rest of the nodes in the cluster. The error message you got means that all the nodes responded successfully to the first phase, and on the second phase of the commit, one of the nodes encountered an error. At this point the change was applied to the other nodes, and the node with the error was purposely disconnected from the cluster because it is in an inconsistent state. If possible, can you see what other errors happened in the log of that node before seeing "host out of cluster..."? because the real problem is there was some other issue on that node that caused it to fail. -Bryan On Wed, Nov 9, 2016 at 5:45 AM, Alessio Palma mailto:alessio.pa...@docomodigital.com>> wrote: Hello all, I experienced "host out of the cluster which was no longer able to join", log reports configuration workflow has been changed and it's different from the one running into the cluster. Due to this issue there is not way to join again the cluster. To resolve this I stopped the whole cluster and copied the same configuration to every host. After the restart anything worked well. Is here a good way to prevent flow changes when all the host into the cluster are not connected ?
