Re: flow.xml sync

[Andy LoPresto]

Placing a flow.xml.gz file on each node before starting the cluster should not 
cause any problems as long as the flow.xml.gz files are identical. If the flows 
differ, the cluster will not be able to start up (superficial discrepancies can 
be resolved automatically, but any value differences will cause problems). 

A (healthy) cluster will always sync the flow between all nodes. This is 
because multiple users can interact with the flow on any node’s web server, and 
the flow must reflect the most accurate state (this is handled with two-phase 
commits on flow changes). 

If a primary node is lost or disconnected, ZK performs a new election to 
determine the replacement primary node. 

Processors which only run on the primary node are configured via the processor 
configuration, which you can update via the UI or API. 

You cannot explicitly determine the primary node; it is the result of the ZK 
election at runtime. 


Andy LoPresto
alopre...@apache.org
alopresto.apa...@gmail.com
PGP Fingerprint: 70EC B3E5 98A6 5A3F D3C4  BACE 3C6E F65B 2F7D EF69

> On Jul 24, 2019, at 3:08 AM, Clay Teahouse  wrote:
> 
> According to the NiFi documentation, zookeeper decides on the primary node, 
> when the system starts. So that answers my question. Now my question is how 
> to designate where to run the isolated processes without the NiFi UI? thanks.
> 
> On Wed, Jul 24, 2019 at 4:50 AM Clay Teahouse  > wrote:
> Hi Everyone,
> I have a cluster of multiple nodes. If I place flow.xml on all of them before 
> starting the nodes, would that cause a conflict? If yes, can I disable 
> syncing between the nodes? I do not want to have to decide on a primary node 
> at the start up.
> In other words, can the primary node be decided on the run time?
> 
> thank you
> Clay.

Re: flow.xml sync

[Clay Teahouse]

According to the NiFi documentation, zookeeper decides on the primary node,
when the system starts. So that answers my question. Now my question is how
to designate where to run the isolated processes without the NiFi UI?
thanks.

On Wed, Jul 24, 2019 at 4:50 AM Clay Teahouse 
wrote:

> Hi Everyone,
> I have a cluster of multiple nodes. If I place flow.xml on all of them
> before starting the nodes, would that cause a conflict? If yes, can I
> disable syncing between the nodes? I do not want to have to decide on a
> primary node at the start up.
> In other words, can the primary node be decided on the run time?
>
> thank you
> Clay.
>

flow.xml sync

[Clay Teahouse]

Hi Everyone,
I have a cluster of multiple nodes. If I place flow.xml on all of them
before starting the nodes, would that cause a conflict? If yes, can I
disable syncing between the nodes? I do not want to have to decide on a
primary node at the start up.
In other words, can the primary node be decided on the run time?

thank you
Clay.